



Internet Engineering Task Force                               M. Spencer
Internet-Draft                                                 Avilution
Intended status: Informational                             E.T. Guy, Ed.
Expires: 22 June 2026                                          Bloomberg
                                                              N. Hartley
                                                               Avilution
                                                        19 December 2025


              eXtensible Stateless Equipment Data Exchange
                           draft-guy-xfsp-03

Abstract

   This document presents a binary IP-based protocol to facilitate
   interoperable communications between electronic equipment on a
   platform.  The protocol is UDP-based, stateless, and multicast.
   Messages consist of a common header followed by a series of
   parameters and related attributes.  The parameters are always
   informational, e.g., indicating airspeed is 150 kts, but parameter
   attributes can be set to indicate intent, e.g., this parameter
   contains a new user selected value such as an instruction that
   deploys the landing gear.  Although initially designed for avionics,
   it can be applied to other platform domains as well.  This document
   defines the core protocol and a method to extend it to meet any
   domain specific needs.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
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   This Internet-Draft will expire on 22 June 2026.

Copyright Notice

   Copyright (c) 2025 IETF Trust and the persons identified as the
   document authors.  All rights reserved.



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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Basic Properties  . . . . . . . . . . . . . . . . . . . .   4
     1.2.  Drawbacks . . . . . . . . . . . . . . . . . . . . . . . .   5
     1.3.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   6
   2.  Overview of XSEDE Protocol  . . . . . . . . . . . . . . . . .   6
   3.  xfsdatamodel  . . . . . . . . . . . . . . . . . . . . . . . .   8
     3.1.  structures  . . . . . . . . . . . . . . . . . . . . . . .   8
       3.1.1.  structure . . . . . . . . . . . . . . . . . . . . . .   8
       3.1.2.  paramformat . . . . . . . . . . . . . . . . . . . . .  16
     3.2.  dictionaries  . . . . . . . . . . . . . . . . . . . . . .  17
       3.2.1.  dictionary  . . . . . . . . . . . . . . . . . . . . .  17
     3.3.  ranges  . . . . . . . . . . . . . . . . . . . . . . . . .  20
       3.3.1.  range . . . . . . . . . . . . . . . . . . . . . . . .  20
     3.4.  params  . . . . . . . . . . . . . . . . . . . . . . . . .  22
       3.4.1.  param . . . . . . . . . . . . . . . . . . . . . . . .  22
   4.  Message Format  . . . . . . . . . . . . . . . . . . . . . . .  23
     4.1.  Message Header  . . . . . . . . . . . . . . . . . . . . .  23
       4.1.1.  Message Header Dictionaries . . . . . . . . . . . . .  25
     4.2.  Message Parameter Format  . . . . . . . . . . . . . . . .  29
       4.2.1.  Parameter Header Dictionaries . . . . . . . . . . . .  31
       4.2.2.  Expire Encoding . . . . . . . . . . . . . . . . . . .  32
     4.3.  Parameter Attribute Formats . . . . . . . . . . . . . . .  33
       4.3.1.  BOOL Parameter Format . . . . . . . . . . . . . . . .  33
       4.3.2.  UINT Parameter Format . . . . . . . . . . . . . . . .  34
       4.3.3.  WAYPOINT Parameter Format . . . . . . . . . . . . . .  34
       4.3.4.  STRING Parameter Format . . . . . . . . . . . . . . .  40
       4.3.5.  CASMSG Parameter Format . . . . . . . . . . . . . . .  40
       4.3.6.  NULL Parameter Format . . . . . . . . . . . . . . . .  43
       4.3.7.  SINT Parameter Format . . . . . . . . . . . . . . . .  43
       4.3.8.  BUS Parameter Format  . . . . . . . . . . . . . . . .  43
       4.3.9.  RANGE Parameter Format  . . . . . . . . . . . . . . .  46
       4.3.10. GPIO Parameter Format . . . . . . . . . . . . . . . .  49
       4.3.11. APP Parameter Format  . . . . . . . . . . . . . . . .  49
       4.3.12. UPDATE Parameter Format . . . . . . . . . . . . . . .  52
       4.3.13. SERVO Parameter Format  . . . . . . . . . . . . . . .  53
       4.3.14. DBASE Parameter Format  . . . . . . . . . . . . . . .  54
       4.3.15. DATETIME Parameter Format . . . . . . . . . . . . . .  55



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     4.4.  Native Structures . . . . . . . . . . . . . . . . . . . .  57
       4.4.1.  Structures  . . . . . . . . . . . . . . . . . . . . .  57
     4.5.  Parameter Ranges  . . . . . . . . . . . . . . . . . . . .  64
       4.5.2.  Ranges  . . . . . . . . . . . . . . . . . . . . . . .  64
     4.6.  Dictionary Types  . . . . . . . . . . . . . . . . . . . .  67
     4.7.  Parameter Types . . . . . . . . . . . . . . . . . . . . . 104
   5.  Message Transport . . . . . . . . . . . . . . . . . . . . . . 170
     5.1.  Message Composition . . . . . . . . . . . . . . . . . . . 170
     5.2.  Message Transmission and Reliability  . . . . . . . . . . 171
     5.3.  Message Reception & decoding  . . . . . . . . . . . . . . 171
     5.4.  Message Signing . . . . . . . . . . . . . . . . . . . . . 172
   6.  Example Message Flows . . . . . . . . . . . . . . . . . . . . 172
     6.1.  Adjust radio  . . . . . . . . . . . . . . . . . . . . . . 172
       6.1.1.  Message Header  . . . . . . . . . . . . . . . . . . . 172
       6.1.2.  Frequency Message Header  . . . . . . . . . . . . . . 173
       6.1.3.  Squelch Message Header  . . . . . . . . . . . . . . . 174
       6.1.4.  Radio Status Report . . . . . . . . . . . . . . . . . 175
     6.2.  Deploy Landing Gear Example . . . . . . . . . . . . . . . 177
       6.2.1.  Initial Gear State Message  . . . . . . . . . . . . . 177
       6.2.2.  Gear Position Request . . . . . . . . . . . . . . . . 180
       6.2.3.  First Changed Gear State Message  . . . . . . . . . . 182
       6.2.4.  Final Gear State Message  . . . . . . . . . . . . . . 185
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . 188
   8.  Security Considerations . . . . . . . . . . . . . . . . . . . 188
     8.1.  Interception  . . . . . . . . . . . . . . . . . . . . . . 189
     8.2.  Impersonation and MITM  . . . . . . . . . . . . . . . . . 189
     8.3.  Denial of Service . . . . . . . . . . . . . . . . . . . . 189
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . . 189
     9.1.  Normative References  . . . . . . . . . . . . . . . . . . 189
     9.2.  Informative References  . . . . . . . . . . . . . . . . . 190
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . . 190

1.  Introduction

   Historically, avionics and other networked equipment platforms have
   used private protocols for device interconnection but the trend is
   towards open communication leveraging standard hardware.  There have
   been various stages in the evolution of device interconnection from
   point-to-point analog communication to digital serial protocols, to
   bus-based solutions and currently IP-based over ethernet.

   One of the concerns with all of these protocols in this industry is
   that extensive testing is required, so developing a common protocol
   and library with its extensive test cases will improve time to
   market, product quality and safety, and lower cost.






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   The eXtensible Stateless Equipment Data Exchange, XSEDE, is such an
   IP-based protocol which provides a common means that facilitates
   parameter communication between networked equipment.  It is an open
   protocol which typically operates by sending binary-encoded data in
   UDP packets using common Multicast over Ethernet.  Typical
   implementation environments contain legacy networks such as CAN bus
   and components that have various levels of certification, e.g.,
   levels per DO-178 [DO-178C].  This approach allows the networked
   platform to function as a collection of safety-critical microservices
   with XSEDE at the hub.  XSEDE can flexibly drive multiple displays
   and unify all the subsystems all at the control of the system
   integrator.

   Parameters generally fall into two separate categories: schedule-
   driven and event-driven.  Schedule-driven parameters are those that
   are sent periodically by the nodes in the system.  One example could
   be the current heading might be reported by a sensor at 10hz.  These
   parameters have a logical expiration time associated with how long
   they are valid, for example, 250ms.  Another example could be the
   current air temperature or even the current value of the pilot's
   desired heading (heading bug.)  Event driven parameters are those
   that occur in response to an external stimuli, e.g., a pilot action
   on a switch, or an autopilot deciding to change the heading due to
   reaching an intermediate waypoint.  These parameters do not have a
   logical expiration time associated with how long they are valid.

1.1.  Basic Properties

   XSEDE is a simple and compact protocol which uses a fast marshaling
   approach.  Parameters may be coalesced, size and time permitting,
   into a single message to make transport more efficient.  The message
   layout considers four octet alignment issues which can affect
   performance, especially on ARM-based architectures and pads to
   maintain efficiency.  All messages are sent to all receivers so that
   the protocol is stateless and only the recipient controls whether a
   parameter will be processed.  Since avionics software is subject to
   intensive testing and validation, XSEDE is designed to be
   deterministic with the fewest number of formal requirements required
   for implementation while still permitting the addition of new data
   formats and parameters through an extensible data model.  The
   parameter identifier is designed to allow for either global data
   model additions so all nodes are aware or local data model additions
   if the parameter is only relevant to a subset of nodes.

   User and System selected events can exhibit two distinct behaviors:
   an event that causes an immediate change, e.g., a radio frequency
   change, and those changes in which a change may take time to be
   reflected by the system, e.g., selecting a new flap position.  In the



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   former case, only one parameter is defined: a request would set the
   confidence field to USERSEL (or SYSSEL).  At the same time, the radio
   would periodically report with the current setting.  In the latter
   case, these settings are implemented with a pair of parameters, a
   request (REQ suffix) and a current state Parameter that has no
   specific suffix.  For example, FLAPREQ and FLAPPOS (See Section 4.7)
   where the first indicates the requested value and the second
   indicates the actual value.

   An example of the stateless nature of the protocol can be seen when
   comparing sample use cases of a few parameters (See Section 4.7).
   The first example is a simple system with a user interface node and a
   radio control node where the user interface node sends a COMFREQ
   parameter in an XSEDE message to set the radio frequency.  The time
   for the frequency change to be reported is generally negligible, so a
   COMFREQ parameter with a confidence of USERSEL/SYSSEL for setting the
   frequency and a COMFREQ parameter with a confidence of RAW from the
   radio control node for reporting the current frequency is usually
   sufficient.  The second example is a system with a user interface
   node and a flap control node where the user interface node would send
   a FLAPREQ parameter and then report the FLAPPOS parameter sent by the
   flap control node to inform the pilot of the current state of the
   flaps.  This allows the user interface to be able to set a requested
   flap state without having to worry about the transition period for a
   given systems flaps while not precluding the ability to generate a
   CAS message if the flaps do not change position in a specific amount
   of time.

1.2.  Drawbacks

   XSEDE is a UDP-based protocol so packet delivery is not guaranteed.
   XSEDE is typically run on a purpose built network within a specific
   aircraft or other high reliability networks, therefore the `best-
   effort` nature of UDP is not of grave concern.  Application-level
   behavior is implemented to ensure critical requests are executed.
   Since the protocol is stateless, it relies on the requestor to
   monitor status to ensure an action was taken.  For example, if a
   request to put the landing gear down is made, the requesting
   application must watch reports of the landing gear position and alert
   if the request is not satisfied in a timely manner.  However, you
   would be able to see if your request was correctly interpreted by a
   report, periodic or in response to the event, by the responsible
   nodes.  Notably, the protocol does not contain the concept of
   incrementing or decrementing a value, just setting a specific value.
   A user interface which is designed to increment and decrement a value
   based on a user turning a knob, for example, must track the current
   value and when an increment is detected, transmit the new,
   incremented value with the appropriate confidence (most likely



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   USERSEL).  If two or more applications are monitoring the same knob
   from two different computers, they each would be able to redundantly
   send the same new value without affecting the behavior whether one,
   two or more such applications were concurrently running.

1.3.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   Message:
      is the basic unit of communication in XSEDE.

   Node:
      is a device or process that implements XSEDE.

   Parameter:
      is the task specific payload contained in a message.

   Attribute Format:
      are the simple and structured data types associated with a
      parameter attribute.

   Attributes:
      are the values associated with a parameter.

   Dictionary:
      is a set of allowed values associated with an attribute,
      parameter, or message field.

   Source ID:
      Refers to the unique number which identifies the node, by
      convention with the upper octet representing the computer and the
      lower octet representing the application number within that
      computer.

2.  Overview of XSEDE Protocol

   The eXtensible Stateless Equipment Data Exchange is designed to
   operate on an integrated local network and comprises instruments,
   displays, sensors, and actuators performing various functions.  XSEDE
   messages are sent to every node on the network.  XSEDE messages are
   currently in one of three classes: Maintenance, Operational and Raw.





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   Maintenance and Operational messages consist of a header followed by
   a series of parameters.  Parameters always represent information, a
   message is purely a collection of parameters.  However, the
   confidence field must be interpreted to determine intent, i.e., the
   SYSSEL and USERSEL confidence levels MUST be interpreted by
   responsible nodes to affect changes on the relevant items.

   XSEDE is stateless.  There is no required protocol level response to
   any command, however, informational responses may be made.  For
   instance, a command to change the radio frequency of a certain radio
   may generate a application-level response indicating the new radio
   frequency.  All XSEDE messages go to all nodes which ignore messages
   by checking for relevant parameters by identifier.

   Raw XSEDE messages consist of a message header which specifies the
   length of the raw data, followed by that raw data.  Raw data is
   classified as MIL-STD-1553, CANbus, digital samples, GDL90 data
   [GDL90], or other serial or streaming unframed data.

   Each node in XSEDE is assigned a source ID.  These Source IDs MUST be
   unique within the XSEDE network.  The Source ID and the message
   number uniquely identify the message and are contained in the message
   header.  Message IDs created by a node MUST be monotonically
   increasing.  A receiving node MUST ignore all duplicate messages.
   The Source ID and a message number are used to ensure messages are
   processed in order and only once.  Messages MUST be processed in
   order skipping any missing messages and MUST only be processed once.
   Senders and Receivers must account for integer overflow in message
   numbers.  There is no retry mechanism at the protocol level; Missing
   and out-of-order messages SHALL be considered lost and if received
   out of order, a message MUST be ignored.

   In addition to the Source ID and Message Number, The XSEDE message
   header also contains the message class, the Message Operation ID,
   Flags, [DO-178C] the confidence level currently for Avionics, and the
   payload length.

   For best performance, an XSEDE goal is to not send IP datagrams that
   have to be fragmented.  Packets which exceed the MSS size will be
   fragmented.  To achieve this goal XSEDE messages SHOULD be less than
   the network Maximum Segment Size (MSS) size in length.  On a modern
   Ethernet network, IEEE 802.3 [IEEE8023] specifies a standard maximum
   payload size of 1500 bytes.  The size of the fixed IPv4 header is 20
   bytes [RFC0791] or in IPv6 the fixed header is 40 bytes [RFC2640] UDP
   headers consume 8 bytes, [RFC0768] the XSEDE header Section 4.1 uses
   12 bytes leaving 1460 bytes for parameters or 1440 bytes on an IPv6
   network.




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3.  xfsdatamodel

   The xfsdatamodel tag is the root element for the XSEDE XML datamodel.
   The following subsections show the descendant elements and their
   attributes.

3.1.  structures

3.1.1.  structure

   +============+===========+===============================+=========+
   | Attribute  | Mandatory | Definition                    | Default |
   +============+===========+===============================+=========+
   | name       | Yes       | Mandatory name for this       | No      |
   |            |           | parameter format which may    |         |
   |            |           | only contain lower case       |         |
   |            |           | letters a-z, underscore ('_') |         |
   |            |           | and digits 0-9 after the      |         |
   |            |           | first non-digit character.    |         |
   +------------+-----------+-------------------------------+---------+
   | definition | No        | Human readable description of | No      |
   |            |           | the purpose of this item.     |         |
   +------------+-----------+-------------------------------+---------+

                            Table 1: structure

3.1.1.1.  int8 - 8-bit two's complement signed integer

   +===========+===========+================================+=========+
   | Attribute | Mandatory | Definition                     | Default |
   +===========+===========+================================+=========+
   | length    | No        | If specified, this field is    | No      |
   |           |           | actually an array of this      |         |
   |           |           | length.  Note that charrays    |         |
   |           |           | can have a length of zero only |         |
   |           |           | if at the end of a structure,  |         |
   |           |           | implying there will be a       |         |
   |           |           | buffer immediately following.  |         |
   +-----------+-----------+--------------------------------+---------+
   | divisor   | No        | If specified, the the value of | No      |
   |           |           | this field is divided by this  |         |
   |           |           | to obtain a (floating point)   |         |
   |           |           | number of units.               |         |
   +-----------+-----------+--------------------------------+---------+
   | minval    | No        | The minimum valid value can be | No      |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | maxval    | No        | The maximum valid value can be | No      |



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   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | clowval   | No        | The value below which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | chighval  | No        | The value above which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | units     | No        | What units (e.g. seconds,      | No      |
   |           |           | pounds, etc) is this field     |         |
   |           |           | provided in?  The units must   |         |
   |           |           | exist in the param_units       |         |
   |           |           | dictionary.                    |         |
   +-----------+-----------+--------------------------------+---------+
   | interpret | No        | If specified, interpret this   | No      |
   |           |           | field using the given          |         |
   |           |           | Dictionary                     |         |
   +-----------+-----------+--------------------------------+---------+
   | defrange  | No        | If specified, references a     | No      |
   |           |           | predefined range for           |         |
   |           |           | interpretation of the value.   |         |
   +-----------+-----------+--------------------------------+---------+

                              Table 2: int8

3.1.1.2.  uint8 - 8-bit unsigned integer

   +===========+===========+================================+=========+
   | Attribute | Mandatory | Definition                     | Default |
   +===========+===========+================================+=========+
   | length    | No        | If specified, this field is    | No      |
   |           |           | actually an array of this      |         |
   |           |           | length.  Note that charrays    |         |
   |           |           | can have a length of zero only |         |
   |           |           | if at the end of a structure,  |         |
   |           |           | implying there will be a       |         |
   |           |           | buffer immediately following.  |         |
   +-----------+-----------+--------------------------------+---------+
   | divisor   | No        | If specified, the the value of | No      |
   |           |           | this field is divided by this  |         |
   |           |           | to obtain a (floating point)   |         |
   |           |           | number of units.               |         |
   +-----------+-----------+--------------------------------+---------+
   | minval    | No        | The minimum valid value can be | No      |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+



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   | maxval    | No        | The maximum valid value can be | No      |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | clowval   | No        | The value below which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | chighval  | No        | The value above which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | units     | No        | What units (e.g. seconds,      | No      |
   |           |           | pounds, etc) is this field     |         |
   |           |           | provided in?  The units must   |         |
   |           |           | exist in the param_units       |         |
   |           |           | dictionary.                    |         |
   +-----------+-----------+--------------------------------+---------+
   | interpret | No        | If specified, interpret this   | No      |
   |           |           | field using the given          |         |
   |           |           | Dictionary                     |         |
   +-----------+-----------+--------------------------------+---------+
   | defrange  | No        | If specified, references a     | No      |
   |           |           | predefined range for           |         |
   |           |           | interpretation of the value.   |         |
   +-----------+-----------+--------------------------------+---------+

                              Table 3: uint8

3.1.1.3.  int16 - 16-bit two's complement signed integer

   +===========+===========+================================+=========+
   | Attribute | Mandatory | Definition                     | Default |
   +===========+===========+================================+=========+
   | length    | No        | If specified, this field is    | No      |
   |           |           | actually an array of this      |         |
   |           |           | length.  Note that charrays    |         |
   |           |           | can have a length of zero only |         |
   |           |           | if at the end of a structure,  |         |
   |           |           | implying there will be a       |         |
   |           |           | buffer immediately following.  |         |
   +-----------+-----------+--------------------------------+---------+
   | divisor   | No        | If specified, the the value of | No      |
   |           |           | this field is divided by this  |         |
   |           |           | to obtain a (floating point)   |         |
   |           |           | number of units.               |         |
   +-----------+-----------+--------------------------------+---------+
   | minval    | No        | The minimum valid value can be | No      |
   |           |           | found in this field            |         |



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   +-----------+-----------+--------------------------------+---------+
   | maxval    | No        | The maximum valid value can be | No      |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | clowval   | No        | The value below which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | chighval  | No        | The value above which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | units     | No        | What units (e.g. seconds,      | No      |
   |           |           | pounds, etc) is this field     |         |
   |           |           | provided in?  The units must   |         |
   |           |           | exist in the param_units       |         |
   |           |           | dictionary.                    |         |
   +-----------+-----------+--------------------------------+---------+
   | interpret | No        | If specified, interpret this   | No      |
   |           |           | field using the given          |         |
   |           |           | Dictionary                     |         |
   +-----------+-----------+--------------------------------+---------+
   | defrange  | No        | If specified, references a     | No      |
   |           |           | predefined range for           |         |
   |           |           | interpretation of the value.   |         |
   +-----------+-----------+--------------------------------+---------+

                              Table 4: int16

3.1.1.4.  uint16 - 16-bit unsigned integer

   +===========+===========+================================+=========+
   | Attribute | Mandatory | Definition                     | Default |
   +===========+===========+================================+=========+
   | length    | No        | If specified, this field is    | No      |
   |           |           | actually an array of this      |         |
   |           |           | length.  Note that charrays    |         |
   |           |           | can have a length of zero only |         |
   |           |           | if at the end of a structure,  |         |
   |           |           | implying there will be a       |         |
   |           |           | buffer immediately following.  |         |
   +-----------+-----------+--------------------------------+---------+
   | divisor   | No        | If specified, the the value of | No      |
   |           |           | this field is divided by this  |         |
   |           |           | to obtain a (floating point)   |         |
   |           |           | number of units.               |         |
   +-----------+-----------+--------------------------------+---------+
   | minval    | No        | The minimum valid value can be | No      |



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   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | maxval    | No        | The maximum valid value can be | No      |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | clowval   | No        | The value below which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | chighval  | No        | The value above which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | units     | No        | What units (e.g. seconds,      | No      |
   |           |           | pounds, etc) is this field     |         |
   |           |           | provided in?  The units must   |         |
   |           |           | exist in the param_units       |         |
   |           |           | dictionary.                    |         |
   +-----------+-----------+--------------------------------+---------+
   | interpret | No        | If specified, interpret this   | No      |
   |           |           | field using the given          |         |
   |           |           | Dictionary                     |         |
   +-----------+-----------+--------------------------------+---------+
   | defrange  | No        | If specified, references a     | No      |
   |           |           | predefined range for           |         |
   |           |           | interpretation of the value.   |         |
   +-----------+-----------+--------------------------------+---------+

                             Table 5: uint16

3.1.1.5.  int32 - 32-bit two's complement signed integer

   +===========+===========+================================+=========+
   | Attribute | Mandatory | Definition                     | Default |
   +===========+===========+================================+=========+
   | length    | No        | If specified, this field is    | No      |
   |           |           | actually an array of this      |         |
   |           |           | length.  Note that charrays    |         |
   |           |           | can have a length of zero only |         |
   |           |           | if at the end of a structure,  |         |
   |           |           | implying there will be a       |         |
   |           |           | buffer immediately following.  |         |
   +-----------+-----------+--------------------------------+---------+
   | divisor   | No        | If specified, the the value of | No      |
   |           |           | this field is divided by this  |         |
   |           |           | to obtain a (floating point)   |         |
   |           |           | number of units.               |         |
   +-----------+-----------+--------------------------------+---------+



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   | minval    | No        | The minimum valid value can be | No      |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | maxval    | No        | The maximum valid value can be | No      |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | clowval   | No        | The value below which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | chighval  | No        | The value above which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | units     | No        | What units (e.g. seconds,      | No      |
   |           |           | pounds, etc) is this field     |         |
   |           |           | provided in?  The units must   |         |
   |           |           | exist in the param_units       |         |
   |           |           | dictionary.                    |         |
   +-----------+-----------+--------------------------------+---------+
   | interpret | No        | If specified, interpret this   | No      |
   |           |           | field using the given          |         |
   |           |           | Dictionary                     |         |
   +-----------+-----------+--------------------------------+---------+
   | defrange  | No        | If specified, references a     | No      |
   |           |           | predefined range for           |         |
   |           |           | interpretation of the value.   |         |
   +-----------+-----------+--------------------------------+---------+

                              Table 6: int32

3.1.1.6.  uint32 - 32-bit unsigned integer

   +===========+===========+================================+=========+
   | Attribute | Mandatory | Definition                     | Default |
   +===========+===========+================================+=========+
   | length    | No        | If specified, this field is    | No      |
   |           |           | actually an array of this      |         |
   |           |           | length.  Note that charrays    |         |
   |           |           | can have a length of zero only |         |
   |           |           | if at the end of a structure,  |         |
   |           |           | implying there will be a       |         |
   |           |           | buffer immediately following.  |         |
   +-----------+-----------+--------------------------------+---------+
   | divisor   | No        | If specified, the the value of | No      |
   |           |           | this field is divided by this  |         |
   |           |           | to obtain a (floating point)   |         |
   |           |           | number of units.               |         |



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   +-----------+-----------+--------------------------------+---------+
   | minval    | No        | The minimum valid value can be | No      |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | maxval    | No        | The maximum valid value can be | No      |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | clowval   | No        | The value below which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | chighval  | No        | The value above which caution  | No      |
   |           |           | should be exercised can be     |         |
   |           |           | found in this field            |         |
   +-----------+-----------+--------------------------------+---------+
   | units     | No        | What units (e.g. seconds,      | No      |
   |           |           | pounds, etc) is this field     |         |
   |           |           | provided in?  The units must   |         |
   |           |           | exist in the param_units       |         |
   |           |           | dictionary.                    |         |
   +-----------+-----------+--------------------------------+---------+
   | interpret | No        | If specified, interpret this   | No      |
   |           |           | field using the given          |         |
   |           |           | Dictionary                     |         |
   +-----------+-----------+--------------------------------+---------+
   | defrange  | No        | If specified, references a     | No      |
   |           |           | predefined range for           |         |
   |           |           | interpretation of the value.   |         |
   +-----------+-----------+--------------------------------+---------+

                             Table 7: uint32

3.1.1.7.  charray - 8-bit ISO-8859 encoded character string, NUL (0)
          terminated

   +============+===========+================================+=========+
   | Attribute  | Mandatory | Definition                     | Default |
   +============+===========+================================+=========+
   | length     | Yes       | If specified, this field       | No      |
   |            |           | is actually an array of        |         |
   |            |           | this length.  Note that        |         |
   |            |           | charrays can have a length     |         |
   |            |           | of zero only if at the end     |         |
   |            |           | of a structure, implying       |         |
   |            |           | there will be a buffer         |         |
   |            |           | immediately following.         |         |
   +------------+-----------+--------------------------------+---------+
   | name       | Yes       | Mandatory name for this        | No      |



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   |            |           | parameter format which may     |         |
   |            |           | only contain lower case        |         |
   |            |           | letters a-z, underscore        |         |
   |            |           | ('_') and digits 0-9 after     |         |
   |            |           | the first non-digit            |         |
   |            |           | character.                     |         |
   +------------+-----------+--------------------------------+---------+
   | definition | No        | Human readable description     | No      |
   |            |           | of the purpose of this         |         |
   |            |           | item.                          |         |
   +------------+-----------+--------------------------------+---------+

                              Table 8: charray

3.1.1.8.  struct - A previously defined structure

   +============+===========+===============================+=========+
   | Attribute  | Mandatory | Definition                    | Default |
   +============+===========+===============================+=========+
   | struct     | Yes       |                               | No      |
   +------------+-----------+-------------------------------+---------+
   | name       | Yes       | Mandatory name for this       | No      |
   |            |           | parameter format which may    |         |
   |            |           | only contain lower case       |         |
   |            |           | letters a-z, underscore ('_') |         |
   |            |           | and digits 0-9 after the      |         |
   |            |           | first non-digit character.    |         |
   +------------+-----------+-------------------------------+---------+
   | definition | No        | Human readable description of | No      |
   |            |           | the purpose of this item.     |         |
   +------------+-----------+-------------------------------+---------+

                             Table 9: struct

3.1.1.9.  starray - Array of another previously defined structure

   +============+===========+================================+=========+
   | Attribute  | Mandatory | Definition                     | Default |
   +============+===========+================================+=========+
   | struct     | Yes       | If specified, references a     | No      |
   |            |           | predefined range for           |         |
   |            |           | interpretation of the          |         |
   |            |           | value.                         |         |
   +------------+-----------+--------------------------------+---------+
   | length     | Yes       | If specified, this field       | No      |
   |            |           | is actually an array of        |         |
   |            |           | this length.  Note that        |         |
   |            |           | charrays can have a length     |         |



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   |            |           | of zero only if at the end     |         |
   |            |           | of a structure, implying       |         |
   |            |           | there will be a buffer         |         |
   |            |           | immediately following.         |         |
   +------------+-----------+--------------------------------+---------+
   | name       | Yes       | Mandatory name for this        | No      |
   |            |           | parameter format which may     |         |
   |            |           | only contain lower case        |         |
   |            |           | letters a-z, underscore        |         |
   |            |           | ('_') and digits 0-9 after     |         |
   |            |           | the first non-digit            |         |
   |            |           | character.                     |         |
   +------------+-----------+--------------------------------+---------+
   | definition | No        | Human readable description     | No      |
   |            |           | of the purpose of this         |         |
   |            |           | item.                          |         |
   +------------+-----------+--------------------------------+---------+

                             Table 10: starray

3.1.2.  paramformat

   +============+===========+================================+=========+
   | Attribute  | Mandatory | Definition                     | Default |
   +============+===========+================================+=========+
   | value      | Yes       | This is the integer ID that    | No      |
   |            |           | is used to uniquely identify   |         |
   |            |           | a parameter format             |         |
   +------------+-----------+--------------------------------+---------+
   | bufferlen  | No        | For parameter formats which    | No      |
   |            |           | end in a charray of length     |         |
   |            |           | zero, this is the maximum      |         |
   |            |           | number of character bytes      |         |
   |            |           | that any parameter could       |         |
   |            |           | contain.                       |         |
   +------------+-----------+--------------------------------+---------+
   | minval     | No        | The minimum valid value can    | No      |
   |            |           | be found in this field         |         |
   +------------+-----------+--------------------------------+---------+
   | maxval     | No        | The maximum valid value can    | No      |
   |            |           | be found in this field         |         |
   +------------+-----------+--------------------------------+---------+
   | clowval    | No        | The value below which caution  | No      |
   |            |           | should be exercised can be     |         |
   |            |           | found in this attribute        |         |
   +------------+-----------+--------------------------------+---------+
   | chighval   | No        | The value below which caution  | No      |
   |            |           | should be exercised can be     |         |



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   |            |           | found in this attribute        |         |
   +------------+-----------+--------------------------------+---------+
   | name       | Yes       | Mandatory name for this        | No      |
   |            |           | parameter format which may     |         |
   |            |           | only contain lower case        |         |
   |            |           | letters a-z, underscore ('_')  |         |
   |            |           | and digits 0-9 after the       |         |
   |            |           | first non-digit character.     |         |
   +------------+-----------+--------------------------------+---------+
   | definition | No        | Human readable description of  | No      |
   |            |           | the purpose of this item.      |         |
   +------------+-----------+--------------------------------+---------+

                           Table 11: paramformat

3.2.  dictionaries

3.2.1.  dictionary

    +============+===========+==============================+=========+
    | Attribute  | Mandatory | Definition                   | Default |
    +============+===========+==============================+=========+
    | default    | No        | If specified, use this name  | UNKNOWN |
    |            |           | for any value that is not    |         |
    |            |           | defined in the dictionary.   |         |
    |            |           | If unspecified, "UNKNOWN" is |         |
    |            |           | used.                        |         |
    +------------+-----------+------------------------------+---------+
    | emptyok    | No        | If set to "true", an empty   | false   |
    |            |           | string is considered an      |         |
    |            |           | encoding of zero rather than |         |
    |            |           | an error and a zero value is |         |
    |            |           | an empty name unless zero is |         |
    |            |           | otherwise defined.           |         |
    +------------+-----------+------------------------------+---------+
    | issigned   | No        | If set to "true", all value  | false   |
    |            |           | fields for dictionary        |         |
    |            |           | entries are considered to be |         |
    |            |           | 32-bit signed integers.      |         |
    |            |           | Otherwise all dictionary     |         |
    |            |           | entry values are considered  |         |
    |            |           | 32-bit unsigned integers.    |         |
    +------------+-----------+------------------------------+---------+
    | mask       | No        | If defined, this integer is  | No      |
    |            |           | used as a default mask for   |         |
    |            |           | the interpretation of non-   |         |
    |            |           | flag values.                 |         |
    +------------+-----------+------------------------------+---------+



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    | numbersok  | No        | If set to true, bare numbers | FALSE   |
    |            |           | that do not have named       |         |
    |            |           | values are permissible.      |         |
    +------------+-----------+------------------------------+---------+
    | immutable  | No        | If set to true, this         | false   |
    |            |           | dictionary may not be        |         |
    |            |           | modified by a future         |         |
    |            |           | dictionary load.             |         |
    +------------+-----------+------------------------------+---------+
    | separator  | No        | If defined, this integer is  | |       |
    |            |           | used as a default mask for   |         |
    |            |           | the interpretation of non-   |         |
    |            |           | flag values.                 |         |
    +------------+-----------+------------------------------+---------+
    | class      | No        | For dictionaries of message  | No      |
    |            |           | subclasses, this specifies   |         |
    |            |           | the msgcl field from the     |         |
    |            |           | msg_class dictionary for     |         |
    |            |           | which this set of subclasses |         |
    |            |           | applies                      |         |
    +------------+-----------+------------------------------+---------+
    | minval     | No        | The minimum valid value for  | No      |
    |            |           | the dictionary if set        |         |
    |            |           | (otherwise all possible      |         |
    |            |           | values of the underlying     |         |
    |            |           | datatype are assumed valid). |         |
    +------------+-----------+------------------------------+---------+
    | maxval     | No        | The minimum valid value for  | No      |
    |            |           | the dictionary if set        |         |
    |            |           | (otherwise all possible      |         |
    |            |           | values of the underlying     |         |
    |            |           | datatype are assumed valid). |         |
    +------------+-----------+------------------------------+---------+
    | type       | No        | Marked external to indicate  | No      |
    |            |           | that there is implementation |         |
    |            |           | needed to perform the        |         |
    |            |           | translation.                 |         |
    +------------+-----------+------------------------------+---------+
    | name       | Yes       | Mandatory name for this      | No      |
    |            |           | parameter format which may   |         |
    |            |           | only contain lower case      |         |
    |            |           | letters a-z, underscore      |         |
    |            |           | ('_') and digits 0-9 after   |         |
    |            |           | the first non-digit          |         |
    |            |           | character.                   |         |
    +------------+-----------+------------------------------+---------+
    | definition | No        | Human readable description   | No      |
    |            |           | of the purpose of this item. |         |



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    +------------+-----------+------------------------------+---------+

                            Table 12: dictionary

3.2.1.1.  entry

    +==============+===========+============================+=========+
    | Attribute    | Mandatory | Definition                 | Default |
    +==============+===========+============================+=========+
    | value        | Yes       | Mandatory unique value in  | No      |
    |              |           | the form of a signed or    |         |
    |              |           | unsigned 32-bit number     |         |
    |              |           | which may be specified     |         |
    |              |           | with an optional shift     |         |
    |              |           | left and in parenthesis.   |         |
    +--------------+-----------+----------------------------+---------+
    | format       | No        | Required for the db_param  | No      |
    |              |           | dictionary to indicate     |         |
    |              |           | what the param_format of   |         |
    |              |           | the parameter is.          |         |
    +--------------+-----------+----------------------------+---------+
    | interpret    | No        | For the db_param if        | No      |
    |              |           | specified, interpret the   |         |
    |              |           | given database parameter   |         |
    |              |           | using the specified        |         |
    |              |           | dictionary.                |         |
    +--------------+-----------+----------------------------+---------+
    | units        | No        | For db_param if specified, | No      |
    |              |           | the units of measure for   |         |
    |              |           | the given database         |         |
    |              |           | parameter                  |         |
    +--------------+-----------+----------------------------+---------+
    | divisor      | No        | For db_param if specified, | No      |
    |              |           | the value should be        |         |
    |              |           | divided by this number to  |         |
    |              |           | determine the (floating    |         |
    |              |           | point) number of units.    |         |
    +--------------+-----------+----------------------------+---------+
    | flag         | No        | If specified with a value  | false   |
    |              |           | of "true", the value is    |         |
    |              |           | treated as a flag that is  |         |
    |              |           | combined with other        |         |
    |              |           | values.  Any value formed  |         |
    |              |           | with a shift is assumed to |         |
    |              |           | be a flag by default.      |         |
    +--------------+-----------+----------------------------+---------+
    | mask         | No        | If specified, this 32-bit  | false   |
    |              |           | mask is applied to the     |         |



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    |              |           | value before comparison    |         |
    |              |           | with the given value.      |         |
    +--------------+-----------+----------------------------+---------+
    | body         | No        | For Maintenance Messages   | false   |
    |              |           | specifies the `structure`  |         |
    |              |           | associated with the body   |         |
    |              |           | of this maintenance        |         |
    |              |           | message.                   |         |
    +--------------+-----------+----------------------------+---------+
    | a661encoding | No        | Used for ARINC-661         | false   |
    |              |           | parameters in A661         |         |
    |              |           | dictionaries as a hint to  |         |
    |              |           | how the data is encoded    |         |
    |              |           | for ARINC-661.             |         |
    +--------------+-----------+----------------------------+---------+
    | name         | Yes       | Mandatory name for this    | No      |
    |              |           | parameter format which may |         |
    |              |           | only contain lower case    |         |
    |              |           | letters a-z, underscore    |         |
    |              |           | ('_') and digits 0-9 after |         |
    |              |           | the first non-digit        |         |
    |              |           | character.                 |         |
    +--------------+-----------+----------------------------+---------+
    | definition   | No        | Human readable description | No      |
    |              |           | of the purpose of this     |         |
    |              |           | item.                      |         |
    +--------------+-----------+----------------------------+---------+

                              Table 13: entry

3.3.  ranges

3.3.1.  range

   +============+===========+===============================+=========+
   | Attribute  | Mandatory | Definition                    | Default |
   +============+===========+===============================+=========+
   | minval     | Yes       | The minimum value for the     | No      |
   |            |           | range.                        |         |
   +------------+-----------+-------------------------------+---------+
   | maxval     | Yes       | The maximum value that the    | No      |
   |            |           | range can have.               |         |
   +------------+-----------+-------------------------------+---------+
   | mindisp    | Yes       | The minimum value when        | No      |
   |            |           | displaying a value            |         |
   |            |           | interpreted with the range    |         |
   |            |           | versus the minimum value that |         |
   |            |           | the range can have.           |         |



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   +------------+-----------+-------------------------------+---------+
   | maxdisp    | Yes       | The maximum value when        | No      |
   |            |           | displaying a value            |         |
   |            |           | interpreted with the range    |         |
   |            |           | versus the maximum value that |         |
   |            |           | the range parameter can have. |         |
   +------------+-----------+-------------------------------+---------+
   | divisor    | No        | For a range the value to      | No      |
   |            |           | divide the ranged parameter   |         |
   |            |           | by prior to interpreting the  |         |
   |            |           | value.                        |         |
   +------------+-----------+-------------------------------+---------+
   | wrap       | No        | A Boolean flag where true     | No      |
   |            |           | indicates that values greater |         |
   |            |           | than the maxval of the range  |         |
   |            |           | should wrap circularly        |         |
   |            |           | starting at the minval of the |         |
   |            |           | range.                        |         |
   +------------+-----------+-------------------------------+---------+
   | numticks   | No        | How many subdivisions of the  | No      |
   |            |           | range there should be (i.e.   |         |
   |            |           | the number of tick marks to   |         |
   |            |           | make in a gauge).             |         |
   +------------+-----------+-------------------------------+---------+
   | name       | Yes       | Mandatory name for this       | No      |
   |            |           | parameter format which may    |         |
   |            |           | only contain lower case       |         |
   |            |           | letters a-z, underscore ('_') |         |
   |            |           | and digits 0-9 after the      |         |
   |            |           | first non-digit character.    |         |
   +------------+-----------+-------------------------------+---------+
   | definition | No        | Human readable description of | No      |
   |            |           | the purpose of this item.     |         |
   +------------+-----------+-------------------------------+---------+

                             Table 14: range

3.3.1.1.  tick

    +===========+===========+===============================+=========+
    | Attribute | Mandatory | Definition                    | Default |
    +===========+===========+===============================+=========+
    | color     | Yes       | The specific color to display | No      |
    |           |           | at the specified value.       |         |
    +-----------+-----------+-------------------------------+---------+
    | value     | Yes       | The specific value at which a | No      |
    |           |           | specified color should be     |         |
    |           |           | displayed.                    |         |



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    +-----------+-----------+-------------------------------+---------+

                               Table 15: tick

3.4.  params

3.4.1.  param

    +============+===========+==============================+=========+
    | Attribute  | Mandatory | Definition                   | Default |
    +============+===========+==============================+=========+
    | value      | Yes       | This is the 21-bit           | No      |
    |            |           | identifier field that will   |         |
    |            |           | be have the length in        |         |
    |            |           | 11-bits prepended to form    |         |
    |            |           | the total parameter          |         |
    |            |           | identifier.                  |         |
    +------------+-----------+------------------------------+---------+
    | format     | Yes       | What the parameter format    | No      |
    |            |           | special structure describes  |         |
    |            |           | how to interpret the data.   |         |
    +------------+-----------+------------------------------+---------+
    | units      | No        | What units (i.e. lbs,        | No      |
    |            |           | degrees Fahrenheit, or       |         |
    |            |           | Knots) the value is given in |         |
    |            |           | specified in a special       |         |
    |            |           | param_units dictionary.      |         |
    +------------+-----------+------------------------------+---------+
    | defrange   | No        | The default range to be used | No      |
    |            |           | to determine if the          |         |
    |            |           | parameter is valid when      |         |
    |            |           | examined.                    |         |
    +------------+-----------+------------------------------+---------+
    | divisor    | No        | The divisor that is applied  | No      |
    |            |           | to the value of this         |         |
    |            |           | parameter before it is sent  |         |
    |            |           | as an XSEDE message.         |         |
    +------------+-----------+------------------------------+---------+
    | length     | No        | For variable length          | No      |
    |            |           | parameter formats, what the  |         |
    |            |           | length of the variable       |         |
    |            |           | portion is in Bytes.         |         |
    +------------+-----------+------------------------------+---------+
    | interpret  | No        | Default dictionary to be     | No      |
    |            |           | used to interpret the value  |         |
    |            |           | of the parameter.            |         |
    +------------+-----------+------------------------------+---------+
    | range      | No        | Boolean value that is used   | No      |



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    |            |           | to signal that a range       |         |
    |            |           | parameter should be          |         |
    |            |           | generated in conjunction     |         |
    |            |           | with the default non-range   |         |
    |            |           | parameter.                   |         |
    +------------+-----------+------------------------------+---------+
    | unitnum    | No        | A human readable             | No      |
    |            |           | interpretation for what a    |         |
    |            |           | unit number means for the    |         |
    |            |           | parameter.  For example, a   |         |
    |            |           | parameter for the source of  |         |
    |            |           | music in an airplane might   |         |
    |            |           | explain the unit number is   |         |
    |            |           | representative of which      |         |
    |            |           | audio panel in the aircraft. |         |
    +------------+-----------+------------------------------+---------+
    | subunitnum | No        | A human readable             | No      |
    |            |           | interpretation for what a    |         |
    |            |           | subunit number means for the |         |
    |            |           | parameter.  For example, a   |         |
    |            |           | parameter for the source of  |         |
    |            |           | music in an airplane might   |         |
    |            |           | explain the standard mapping |         |
    |            |           | of the subunit number to     |         |
    |            |           | crew, passengers, or the     |         |
    |            |           | audio panel as a whole.      |         |
    +------------+-----------+------------------------------+---------+
    | name       | Yes       | Mandatory name for this      | No      |
    |            |           | parameter format which may   |         |
    |            |           | only contain lower case      |         |
    |            |           | letters a-z, underscore      |         |
    |            |           | ('_') and digits 0-9 after   |         |
    |            |           | the first non-digit          |         |
    |            |           | character.                   |         |
    +------------+-----------+------------------------------+---------+
    | definition | No        | Human readable description   | No      |
    |            |           | of the purpose of this item. |         |
    +------------+-----------+------------------------------+---------+

                              Table 16: param

4.  Message Format

4.1.  Message Header







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                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    src id                     |    message number             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   msg class   | message ID    |       flags                   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              tcid             |          len                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
         ...
      :                             Data                              :
         ...
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                      Figure 1: Message Header Format

   XSEDE messages are formatted as shown in the above diagram and
   consist of the following fields:

   src id:
      UINT16; locally configured source ID.  Must be unique on network.

   message number:
      UINT16; monotonically increasing message number.

   msg class:
      UINT8; The message class.  See Table 17

   message ID:
      UINT8; msg-op; See Table 19.

   flags:
      UINT16; See Table 21.

   tcid:
      t-NONE; See Table 22.

   len:
      UINT16 ; length of all parameters or raw data in octets.  Note:
      Operational and Maintenance class messages shall always have a
      length that is a factor or 4.

   data:
      1*(parameter) / *(OCTET) ; raw data may be arbitrary length
      sequence of octets.




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4.1.1.  Message Header Dictionaries

   This section defines the dictionaries used in the message header.
   See Section 4.1.

   Table 17, below, shows the values defined in the msg-class
   Dictionary.  These options represent the XFS common data bus message
   classes.

            +=======+=======+=================================+
            | Name  | Value | Definition                      |
            +=======+=======+=================================+
            | MAINT | %d2   | Maintenance Message             |
            +-------+-------+---------------------------------+
            | OP    | %d3   | Operational Message             |
            +-------+-------+---------------------------------+
            | RAW   | %d4   | Access to raw data stream (e.g. |
            |       |       | RS-232, RS-485, ARINC-429, etc) |
            +-------+-------+---------------------------------+

                       Table 17: msg-class Dictionary

   Table 18, below, shows the values defined in the msg-maint
   Dictionary.  These options represent the Message subclasses for
   maintenance message class.


























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     +==========+=======+===========================================+
     | Name     | Value | Definition                                |
     +==========+=======+===========================================+
     | MXREQ    | %d1   | Request maintenance mode for a specific   |
     |          |       | CPU (or all if cpu is empty)              |
     +----------+-------+-------------------------------------------+
     | MXCHAL   | %d2   | Authentication challenge                  |
     +----------+-------+-------------------------------------------+
     | MXAUTH   | %d3   | Authentication response                   |
     +----------+-------+-------------------------------------------+
     | MXACCEPT | %d4   | Accept authentication request             |
     +----------+-------+-------------------------------------------+
     | MXDENY   | %d5   | Deny maintenance mode                     |
     +----------+-------+-------------------------------------------+
     | MXREADY  | %d6   | Ready for update or diagnostic            |
     +----------+-------+-------------------------------------------+
     | DOUPDATE | %d7   | User Requests System Update.  Note CPU is |
     |          |       | requestor                                 |
     +----------+-------+-------------------------------------------+
     | UPDREQ   | %d8   | Request Update for given Device           |
     +----------+-------+-------------------------------------------+
     | UPDSTAT  | %d9   | Status of Update                          |
     +----------+-------+-------------------------------------------+
     | DODIAG   | %d10  | User Requests System Update.  Note CPU is |
     |          |       | requestor.  Salt is type of diagnostic.   |
     +----------+-------+-------------------------------------------+
     | DIAGREQ  | %d11  | Request diagnostic for given Device.      |
     +----------+-------+-------------------------------------------+
     | DIAGSTAT | %d12  | Status of Update                          |
     +----------+-------+-------------------------------------------+

                      Table 18: msg-maint Dictionary

   Table 19, below, shows the values defined in the msg-op Dictionary.
   These options represent the Message subclasses for operational
   message class.















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     +============+=======+==========================================+
     | Name       | Value | Definition                               |
     +============+=======+==========================================+
     | SUBFLDATA  | %d1   | Subscribe to Aircraft Flight Data Params |
     +------------+-------+------------------------------------------+
     | FLIGHTDATA | %d2   | Flight Data Info                         |
     +------------+-------+------------------------------------------+
     | DEVSTATUS  | %d3   | Device Status                            |
     +------------+-------+------------------------------------------+
     | GDL90      | %d4   | GDL-90 Format Messages without framing,  |
     |            |       | FCS or escape characters                 |
     +------------+-------+------------------------------------------+
     | SUBMSGCLID | %d5   | Subscribe to Specific Message Class and  |
     |            |       | ID                                       |
     +------------+-------+------------------------------------------+

                        Table 19: msg-op Dictionary

   Table 20, below, shows the values defined in the msg-raw Dictionary.
   These options represent the Message subclasses for raw message class.

             +============+=======+==========================+
             | Name       | Value | Definition               |
             +============+=======+==========================+
             | SERIALRX   | %d1   | Serial raw data stream   |
             |            |       | receive from end device  |
             +------------+-------+--------------------------+
             | SERIALTX   | %d2   | Serial raw data stream   |
             |            |       | transmit to end device   |
             +------------+-------+--------------------------+
             | SPIRX      | %d5   | Raw SPI bus receive from |
             |            |       | end device               |
             +------------+-------+--------------------------+
             | SPITX      | %d6   | Raw SPI bus transmit to  |
             |            |       | end device               |
             +------------+-------+--------------------------+
             | ARINC429RX | %d7   | Raw ARINC-429 bus        |
             |            |       | receive from end device  |
             +------------+-------+--------------------------+
             | ARINC429TX | %d8   | Raw ARINC-429 bus        |
             |            |       | transmit to end device   |
             +------------+-------+--------------------------+
             | MIL1553RX  | %d9   | Raw MIL-STD-1553         |
             |            |       | received from end device |
             +------------+-------+--------------------------+
             | MIL1553TX  | %d10  | Raw MIL-STD-1553 bus     |
             |            |       | transmit to end device   |
             +------------+-------+--------------------------+



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             | ECBRX      | %d11  | Raw XFS ECB control      |
             |            |       | receive from end device  |
             +------------+-------+--------------------------+
             | ECBTX      | %d12  | Raw XFS ECB control      |
             |            |       | transmit to end device   |
             +------------+-------+--------------------------+
             | GPIORX     | %d13  | Raw XFS ECB control      |
             |            |       | receive from end device  |
             +------------+-------+--------------------------+
             | GPIOTX     | %d14  | Raw XFS ECB control      |
             |            |       | transmit to end device   |
             +------------+-------+--------------------------+
             | ADCRX      | %d15  | Analog/Digital Converter |
             |            |       | receive from end device  |
             +------------+-------+--------------------------+
             | DACTX      | %d16  | Digital/Analog Converter |
             |            |       | transmit to end device   |
             +------------+-------+--------------------------+
             | CANBUSRX   | %d17  | Raw CAN bus receive from |
             |            |       | end device               |
             +------------+-------+--------------------------+
             | CANBUSTX   | %d18  | Raw CAN bus transmit to  |
             |            |       | end device               |
             +------------+-------+--------------------------+
             | DATAGRAMRX | %d19  | Raw Datagram receive     |
             |            |       | from end device          |
             +------------+-------+--------------------------+
             | DATAGRAMTX | %d20  | Raw Datagram transmit to |
             |            |       | end device               |
             +------------+-------+--------------------------+

                        Table 20: msg-raw Dictionary

   Table 21, below, shows the values defined in the msg-flag-cert
   Dictionary.  These options represent the Message and parameter
   certification level tracking.















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                 +==============+=======+================+
                 | Name         | Value | Definition     |
                 +==============+=======+================+
                 | EXPERIMENTAL | %d0   | Experimental   |
                 +--------------+-------+----------------+
                 | LEVEL-E      | %d1   | DO-178 Level E |
                 +--------------+-------+----------------+
                 | LEVEL-D      | %d2   | DO-178 Level D |
                 +--------------+-------+----------------+
                 | LEVEL-C      | %d3   | DO-178 Level C |
                 +--------------+-------+----------------+
                 | LEVEL-B      | %d4   | DO-178 Level B |
                 +--------------+-------+----------------+
                 | LEVEL-A      | %d5   | DO-178 Level A |
                 +--------------+-------+----------------+

                     Table 21: msg-flag-cert Dictionary

   Table 22, below, shows the values defined in the tcid Dictionary.
   These options represent the XFS transcoder ID values.

     +=========+=========+==========================================+
     | Name    | Value   | Definition                               |
     +=========+=========+==========================================+
     | NONE    | %d0     | No transcoder ID is required or asserted |
     +---------+---------+------------------------------------------+
     | DEFAULT | %d65536 | Pseudo-value to represent global default |
     +---------+---------+------------------------------------------+

                        Table 22: tcid Dictionary

4.2.  Message Parameter Format

   The section defines the elements common to all XSEDE parameters.

















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                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len |                Ident                    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
         ...
      :                  Parameter   Data                             :
         ...
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                     Figure 2: Message Parameter Format

   Unit:
      UINT16 If appropriate, which unit this parameter applies (e.g.,
      Engine #1).

   SubUnit:
      UINT16; If appropriate, which subunit this parameter applies
      (e.g., Engine #2, Cylinder #3).

   Parameter Ident:
      UINT32; This attribute is the composite of the length and a
      parameter specific identifier.

      Nodes MUST compare this value as a whole to their known
      parameters; that is to say, an Ident with a different length is a
      different parameter.  This same Ident with a different length
      situation commonly occurs when sending range parameters but it
      also can happen when parameter definitions are updated.

      If the combined value does not match a known parameter/length
      pair, the parameter data length MUST be determined, then padded to
      a multiple of four, and the parameter MUST be ignored.

      Len:  11 bits; Parameter Data Length in octets.  This value MUST
         reflect the usable length of the parameter data, not including
         padding, however, the parameter itself MUST be padded to a
         length that is a multiple of four octets to maintain proper
         word alignment.

      Ident:  21 bits; XSEDE Parameter Identifier.  See Section 4.7.




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   Format:
      param_format (OCTET): Format of Parameter Data.  See Section 4.3.

   Confidence:
      param_confidence (OCTET): Confidence of data element.  See
      Table 23.

   Expire:
      OCTET; Time to live. %x00 to not expire.  See Section 4.2.2 for
      encoding.

   Pflags:
      msg_flag_cert(OCTET) Reserved Flags, bottom three bits are
      certification level of data.  See Table 21

   Parameter Data:
      *(OCTET) quadword padded payload.

4.2.1.  Parameter Header Dictionaries

   Table 23, below, shows the values defined in the param-confidence
   Dictionary.  These options represent the XFS common bus parameter
   format confidence levels.




























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         +===========+=======+===================================+
         | Name      | Value | Definition                        |
         +===========+=======+===================================+
         | HIGH      | %d100 | Confirmed known value             |
         +-----------+-------+-----------------------------------+
         | USERSEL   | %d90  | User selected value at runtime    |
         +-----------+-------+-----------------------------------+
         | SYSSEL    | %d80  | System selected value at runtime  |
         +-----------+-------+-----------------------------------+
         | INTENTSEL | %d70  | User has indicated intent to make |
         |           |       | a change for this value, but it   |
         |           |       | has not yet been confirmed        |
         +-----------+-------+-----------------------------------+
         | UNANIMOUS | %d50  | Redundant data available and is   |
         |           |       | rationalized                      |
         +-----------+-------+-----------------------------------+
         | RATIONAL  | %d40  | Data being rationalized from      |
         |           |       | other data sources with normal    |
         |           |       | sources ignored                   |
         +-----------+-------+-----------------------------------+
         | VOTED     | %d30  | Data is redundantly verified from |
         |           |       | identical instruments             |
         +-----------+-------+-----------------------------------+
         | SMOOTHED  | %d20  | Smoothed/filtered version of raw  |
         |           |       | data                              |
         +-----------+-------+-----------------------------------+
         | RAW       | %d10  | Raw, unchecked data               |
         +-----------+-------+-----------------------------------+
         | ESTIMATE  | %d5   | Rough estimation                  |
         +-----------+-------+-----------------------------------+
         | USELESS   | %d0   | Value is missing or expected      |
         |           |       | invalid and supplied for          |
         |           |       | debugging ONLY                    |
         +-----------+-------+-----------------------------------+

                   Table 23: param-confidence Dictionary

   The msg_flag_cert Dictionary is also used.  See Table 21 for its
   definition.

4.2.2.  Expire Encoding

   Information provided in messages have a limited usability lifetime or
   time-to-live.  The Expire field is used to indicate how long the
   associated parameter is valid.  It is an eight-bit field that is
   split into an exponent and mantissa to provide the maximum range and
   precision within this small space.  The upper four bits represent the
   the mantissa and the lower four bits represent the exponent.  If the



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   value of the Expire field is %x00, the value MUST be interpreted to
   mean "the parameter does not expire," otherwise the expiry time value
   MUST be determined by the following formula:

   Expiration (milliseconds) = (16 + M) * 2^E which can be implemented
   with ( 0x10 | M ) << E

   This approach give us the range of 17 to 1015880 milliseconds (about
   17 minutes) with 0x00 reserved as "No Expiration."

       0
       0 1 2 3 4 5 6 7
      +-+-+-+-+-+-+-+-+
      |   E   |   M   |
      +-+-+-+-+-+-+-+-+

                     Figure 3: Message Parameter Format

   For example, an expiry value of %x31 gives a mantissa of 0001 and an
   exponent of 0011 yielding a value of (16 + 1) * 2^E ms or 128
   milliseconds.

   Another example, a value of %x7F which decomposes to a mantissa of
   1111 and an exponent of 0111 yielding a value of (16 + 15) * 2^7 ms,
   or 3968 milliseconds.

   The minimum value of %x01 which decomposes to a mantissa of 0001 and
   an exponent of 0000 yielding a value of (16 + 1) * 2^0 ms, or 17
   milliseconds.

   The maximum value of %xFF which decomposes to a mantissa of 1111 and
   an exponent of 1111 yielding a value of (16 + 15) * 2^15 ms, or
   1015808 milliseconds, which is about 17 minutes.

   A final example, %x00 which is a special case for "No Expiration."

4.3.  Parameter Attribute Formats

   The various attributes associated with parameters occur as both
   simple types, such as Integers and compound structures, such as
   Waypoints.  This section defines the attribute formats that are used
   in XSEDE.

4.3.1.  BOOL Parameter Format

   Boolean Format

   Parameter Identifier: %d1



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   Length: 4

   Structure:

           +============+=========+============================+
           | Item       | Type    | Description                |
           +============+=========+============================+
           | bool-value | boolean | Zero for false, 1 for      |
           |            |         | true, all others undefined |
           +------------+---------+----------------------------+

                      Table 24: BOOL Parameter Format

   Table 25, below, shows the values defined in the boolean Dictionary.
   These options represent the Nominal boolean values.

                      +=======+=======+============+
                      | Name  | Value | Definition |
                      +=======+=======+============+
                      | FALSE | %d0   | False      |
                      +-------+-------+------------+
                      | TRUE  | %d1   | True       |
                      +-------+-------+------------+

                       Table 25: boolean Dictionary

4.3.2.  UINT Parameter Format

   Unsigned 32-bit Integer Format

   Parameter Identifier: %d2

   Length: 4

   Structure:

              +============+========+=======================+
              | Item       | Type   | Description           |
              +============+========+=======================+
              | uint-value | uint32 | 32-bit Unsigned Value |
              +------------+--------+-----------------------+

                      Table 26: UINT Parameter Format

4.3.3.  WAYPOINT Parameter Format

   Waypoint on a Flight Plan




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   Parameter Identifier: %d3

   Length: 80

   Structure:

       +===========+===============+===============================+
       | Item      | Type          | Description                   |
       +===========+===============+===============================+
       | label     | 12*12(OCTET)  | Name of waypoint              |
       +-----------+---------------+-------------------------------+
       | lat       | int32         | Latitude of waypoint *        |
       |           |               | 10,000,000                    |
       +-----------+---------------+-------------------------------+
       | lon       | int32         | Longitude of waypoint *       |
       |           |               | 10,000,000                    |
       +-----------+---------------+-------------------------------+
       | lonlen    | int32         | Length of degree of longitude |
       |           |               | for this lattitude in meters  |
       +-----------+---------------+-------------------------------+
       | alt       | int32         | Altitude associated with      |
       |           |               | waypoint in 0.1ft             |
       +-----------+---------------+-------------------------------+
       | minalt    | int32         | Logical Minimum for Fix       |
       |           |               | Crossing in 0.1ft             |
       +-----------+---------------+-------------------------------+
       | maxalt    | int32         | Logical Maximum Altitude for  |
       |           |               | Fix Crossing in 0.1ft         |
       +-----------+---------------+-------------------------------+
       | speed     | int32         | Target indicated airspeed     |
       +-----------+---------------+-------------------------------+
       | magadj    | uint32        | Original (VOR) or Current     |
       |           |               | (GPS) Magnetic Deviation in   |
       |           |               | 0.01 degrees of NAVAID        |
       +-----------+---------------+-------------------------------+
       | inbound   | uint16        | Inbound course in 0.01        |
       |           |               | degrees                       |
       +-----------+---------------+-------------------------------+
       | outbound  | uint16        | Outbound course in 0.01       |
       |           |               | degrees                       |
       +-----------+---------------+-------------------------------+
       | freq      | uint32        | Frequency if this is a NAV    |
       |           |               | AID                           |
       +-----------+---------------+-------------------------------+
       | wtype     | fms-waypoint  | Type of waypoint              |
       +-----------+---------------+-------------------------------+
       | ctype     | fms-container | Type of container             |
       +-----------+---------------+-------------------------------+



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       | flags     | fms-flag      | Flags for the waypoint / leg  |
       +-----------+---------------+-------------------------------+
       | cumete    | uint32        | Cumulative ETE from active    |
       |           |               | waypoint in 0.01 seconds      |
       +-----------+---------------+-------------------------------+
       | cumdis    | uint32        | Cumulative distance from      |
       |           |               | active waypoint in 0.001 nm   |
       +-----------+---------------+-------------------------------+
       | container | 16*16(OCTET)  | What container is this        |
       |           |               | waypoint a part of (e.g.      |
       |           |               | V431, ILS-18L, etc)           |
       +-----------+---------------+-------------------------------+

                    Table 27: WAYPOINT Parameter Format

   Table 28, below, shows the values defined in the fms-waypoint
   Dictionary.  These options represent the Flight management system
   waypoint types.

































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          +============+=======+================================+
          | Name       | Value | Definition                     |
          +============+=======+================================+
          | UNKNOWN    | %d0   | Unknown or unspecified         |
          +------------+-------+--------------------------------+
          | GS         | %x80  | Glideslope component           |
          +------------+-------+--------------------------------+
          | DME        | %x40  | DME Component                  |
          +------------+-------+--------------------------------+
          | TACAN      | %x20  | TACAN Component                |
          +------------+-------+--------------------------------+
          | VOR        | %d1   | VOR Component                  |
          +------------+-------+--------------------------------+
          | LOC        | %d2   | Localizer component            |
          +------------+-------+--------------------------------+
          | NDB        | %d3   | NDB component                  |
          +------------+-------+--------------------------------+
          | LDA        | %d4   | LDA Component                  |
          +------------+-------+--------------------------------+
          | SDF        | %d5   | SDF Component                  |
          +------------+-------+--------------------------------+
          | FIX        | %d6   | Generic RNAV Fix               |
          +------------+-------+--------------------------------+
          | ILS        | %d7   | Complete ILS system            |
          +------------+-------+--------------------------------+
          | AIRPORT    | %d8   | An Airport                     |
          +------------+-------+--------------------------------+
          | DIRECTFROM | %d9   | Starting point of a direct to  |
          +------------+-------+--------------------------------+
          | WEATHER    | %d10  | Weather reporting station only |
          +------------+-------+--------------------------------+

                     Table 28: fms-waypoint Dictionary

   Table 29, below, shows the values defined in the fms-container
   Dictionary.  These options represent the Flight management system
   container types.














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          +=========+=======+==================================+
          | Name    | Value | Definition                       |
          +=========+=======+==================================+
          | UNKNOWN | %d0   | Unspecified or unknown container |
          +---------+-------+----------------------------------+
          | NONE    | %d1   | No container                     |
          +---------+-------+----------------------------------+
          | VICTOR  | %d2   | VOR Airway                       |
          +---------+-------+----------------------------------+
          | JET     | %d3   | Jet Airway                       |
          +---------+-------+----------------------------------+
          | AMBER   | %d4   | Amber Airway                     |
          +---------+-------+----------------------------------+
          | BLUE    | %d5   | Blue Airway                      |
          +---------+-------+----------------------------------+
          | GREEN   | %d6   | Green Airway                     |
          +---------+-------+----------------------------------+
          | RED     | %d7   | Red Airway                       |
          +---------+-------+----------------------------------+
          | Q       | %d8   | RNAV Q Routes                    |
          +---------+-------+----------------------------------+
          | T       | %d9   | RNAV T Routes                    |
          +---------+-------+----------------------------------+
          | STAR    | %d10  | Standard Arrival Procedure       |
          +---------+-------+----------------------------------+
          | DP      | %d11  | Standard Departure Procedure     |
          +---------+-------+----------------------------------+
          | APP     | %d12  | Instrument Approach              |
          +---------+-------+----------------------------------+
          | RWY     | %d13  | Airport Runway Surface Selection |
          +---------+-------+----------------------------------+

                    Table 29: fms-container Dictionary

   Table 30, below, shows the values defined in the fms-flag Dictionary.
   These options represent the Flight management system waypoint and leg
   flags.

       +==============+=========+==================================+
       | Name         | Value   | Definition                       |
       +==============+=========+==================================+
       | NONE         | %d0     | No flags or leg type known       |
       +--------------+---------+----------------------------------+
       | LEGTYPE-VA   | %d1     | Heading to Altitude              |
       +--------------+---------+----------------------------------+
       | LEGTYPE-VD   | %d2     | Heading to DME Distance          |
       +--------------+---------+----------------------------------+
       | LEGTYPE-VI   | %d3     | Heading to Next Leg Intercept    |



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       +--------------+---------+----------------------------------+
       | LEGTYPE-VM   | %d4     | Heading to Manual Termination    |
       +--------------+---------+----------------------------------+
       | LEGTYPE-VR   | %d5     | Heading to Radial Termination    |
       +--------------+---------+----------------------------------+
       | LEGTYPE-CA   | %d6     | Course to an Altitude            |
       +--------------+---------+----------------------------------+
       | LEGTYPE-CD   | %d7     | Course to a DME Distance         |
       +--------------+---------+----------------------------------+
       | LEGTYPE-CI   | %d8     | Course to Next Leg Intercept     |
       +--------------+---------+----------------------------------+
       | LEGTYPE-CR   | %d9     | Course to Radial Termination     |
       +--------------+---------+----------------------------------+
       | LEGTYPE-CF   | %d10    | Course to a Fix                  |
       +--------------+---------+----------------------------------+
       | LEGTYPE-TF   | %d11    | Tracking Between Two Fixes       |
       +--------------+---------+----------------------------------+
       | LEGTYPE-DF   | %d12    | Direct to a Fix                  |
       +--------------+---------+----------------------------------+
       | LEGTYPE-FA   | %d13    | Course from a Fix to an Altitude |
       +--------------+---------+----------------------------------+
       | LEGTYPE-FC   | %d14    | Course from a Fix to an Along    |
       |              |         | Track Distance                   |
       +--------------+---------+----------------------------------+
       | LEGTYPE-FD   | %d15    | Course from a Fix to a DME       |
       |              |         | Distance                         |
       +--------------+---------+----------------------------------+
       | LEGTYPE-FM   | %d16    | Course from a Fix to a Manual    |
       |              |         | Termination                      |
       +--------------+---------+----------------------------------+
       | LEGTYPE-AF   | %d17    | Constant DMA Arc to a Fix        |
       +--------------+---------+----------------------------------+
       | LEGTYPE-HF   | %d18    | Hold to a Fix                    |
       +--------------+---------+----------------------------------+
       | LEGTYPE-HA   | %d19    | Hold to an Altitude              |
       +--------------+---------+----------------------------------+
       | LEGTYPE-HM   | %d20    | Hold to a Manual Termination     |
       +--------------+---------+----------------------------------+
       | LEGTYPE-IF   | %d21    | Initial Fix                      |
       +--------------+---------+----------------------------------+
       | LEGTYPE-PI   | %d22    | Procedure Turn to Intercept      |
       +--------------+---------+----------------------------------+
       | LEGTYPE-RF   | %d23    | Radius to a Fix                  |
       +--------------+---------+----------------------------------+
       | LEGTYPE-MASK | %xff    | Mask with which to retrieve leg  |
       |              |         | type                             |
       +--------------+---------+----------------------------------+
       | FLYOVER      | %x01.00 | If not present, fly by           |



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       +--------------+---------+----------------------------------+
       | DISC         | %x02.00 | If present, Discontinuity before |
       |              |         | current waypoint                 |
       +--------------+---------+----------------------------------+
       | ACTIVE       | %x04.00 | If present, this is the active   |
       |              |         | waypoint                         |
       +--------------+---------+----------------------------------+
       | OBS          | %x08.00 | If present, waypoint allows OBS  |
       |              |         | to be set                        |
       +--------------+---------+----------------------------------+
       | FAF          | %x10.00 | If present, waypoint is final    |
       |              |         | approach fix or after            |
       +--------------+---------+----------------------------------+
       | SUSPEND      | %x20.00 | FMS sequencing is suspended at   |
       |              |         | this waypoint                    |
       +--------------+---------+----------------------------------+
       | LAST         | %x40.00 | This waypoint is the last one in |
       |              |         | the flight plan                  |
       +--------------+---------+----------------------------------+

                       Table 30: fms-flag Dictionary

4.3.4.  STRING Parameter Format

   String of characters (may not have NULL termination)

   Parameter Identifier: %d4

   Length: length(data) + 0

   Structure:

          +==============+==========+===========================+
          | Item         | Type     | Description               |
          +==============+==========+===========================+
          | string-value | *(OCTET) | Optionally NUL terminated |
          |              |          | ISO-8559-1 String         |
          +--------------+----------+---------------------------+

                     Table 31: STRING Parameter Format

4.3.5.  CASMSG Parameter Format

   CAS Message

   Parameter Identifier: %d5

   Length: length(data) + 4



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   Structure:

              +=======+=============+=======================+
              | Item  | Type        | Description           |
              +=======+=============+=======================+
              | level | cas-msglvl  | CAS level             |
              +-------+-------------+-----------------------+
              | rsvd  | uint8       | Reserved, set to 0    |
              +-------+-------------+-----------------------+
              | flags | cas-msgflag | CAS related flags     |
              +-------+-------------+-----------------------+
              | label | *(OCTET)    | Label for CAS Message |
              +-------+-------------+-----------------------+

                     Table 32: CASMSG Parameter Format

   Table 33, below, shows the values defined in the cas-msglvl
   Dictionary.  These options represent the Message levels for CAS
   messages and checklist items.
































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      +===========+=======+========================================+
      | Name      | Value | Definition                             |
      +===========+=======+========================================+
      | CLEAR     | %d0   | Clear a previously issued CAS message  |
      |           |       | -- issue from system only              |
      +-----------+-------+----------------------------------------+
      | DEBUG     | %d1   | In-system debugging output only        |
      +-----------+-------+----------------------------------------+
      | LOG       | %d2   | Log to system log, but do not display  |
      +-----------+-------+----------------------------------------+
      | MAINT     | %d3   | Display only for maintenance purposes  |
      +-----------+-------+----------------------------------------+
      | STATUS    | %d4   | Aircraft system status only            |
      +-----------+-------+----------------------------------------+
      | ADVISORY  | %d5   | Advisory, flight crew should be aware, |
      |           |       | may require later crew response        |
      +-----------+-------+----------------------------------------+
      | CAUTION   | %d6   | Caution, requires immediate flight     |
      |           |       | crew awareness and later response      |
      +-----------+-------+----------------------------------------+
      | WARNING   | %d7   | Warning, requires immediate awareness  |
      |           |       | and response.                          |
      +-----------+-------+----------------------------------------+
      | COMMENT   | %d10  | Checklist Comment Associated with      |
      |           |       | Previous Item                          |
      +-----------+-------+----------------------------------------+
      | UNCHKITEM | %d11  | Unchecked Checklist Item               |
      +-----------+-------+----------------------------------------+
      | CHKITEM   | %d12  | Checked Checklist Item                 |
      +-----------+-------+----------------------------------------+
      | CHKBRANCH | %d13  | Checklist Branch Choice                |
      +-----------+-------+----------------------------------------+
      | PASS      | %d14  | Built-in Test (BIT) Item passed        |
      +-----------+-------+----------------------------------------+
      | INPROG    | %d15  | Built-in Test (BIT) Item in progress   |
      +-----------+-------+----------------------------------------+
      | NOTREQST  | %d16  | Built-in Test (BIT) Item not yet       |
      |           |       | requested                              |
      +-----------+-------+----------------------------------------+
      | INCOMPLT  | %d17  | Built-in Test (BIT) Item test did not  |
      |           |       | complete                               |
      +-----------+-------+----------------------------------------+
      | FAIL      | %d18  | Built-in Test (BIT) Item failed        |
      +-----------+-------+----------------------------------------+

                     Table 33: cas-msglvl Dictionary





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   Table 34, below, shows the values defined in the cas-msgflag
   Dictionary.  These options represent the Additional flags associated
   with CAS messages.

        +======+=======+=========================================+
        | Name | Value | Definition                              |
        +======+=======+=========================================+
        | NONE | %d0   | No additional flags                     |
        +------+-------+-----------------------------------------+
        | AUTO | %x01  | Item is automatically checked/unchecked |
        |      |       | or the test is automatically executed   |
        +------+-------+-----------------------------------------+

                     Table 34: cas-msgflag Dictionary

4.3.6.  NULL Parameter Format

   NULL format

   Parameter Identifier: %d7

4.3.7.  SINT Parameter Format

   Signed 32-bit Integer Format

   Parameter Identifier: %d9

   Length: 4

   Structure:

       +============+=======+======================================+
       | Item       | Type  | Description                          |
       +============+=======+======================================+
       | sint-value | int32 | Signed 32-bit two's complement value |
       +------------+-------+--------------------------------------+

                      Table 35: SINT Parameter Format

4.3.8.  BUS Parameter Format

   Bus and Electronic Circuit Breaker Format

   Parameter Identifier: %d10

   Length: length(data) + 24

   Structure:



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      +==========+===========+=====================================+
      | Item     | Type      | Description                         |
      +==========+===========+=====================================+
      | state    | ecb-state | State of Bus (in terms of ECB)      |
      +----------+-----------+-------------------------------------+
      | ecbflags | ecb-flag  | Flags regarding ECB state           |
      +----------+-----------+-------------------------------------+
      | involts  | int16     | Input Volts on Bus                  |
      +----------+-----------+-------------------------------------+
      | drawamps | int16     | Current draw on bus                 |
      +----------+-----------+-------------------------------------+
      | maxamps  | int16     | Max Amps on bus                     |
      +----------+-----------+-------------------------------------+
      | champs   | int16     | Caution high amps                   |
      +----------+-----------+-------------------------------------+
      | clamps   | int16     | Caution low amps                    |
      +----------+-----------+-------------------------------------+
      | minamps  | int16     | Minimum amps on bus (could be -)    |
      +----------+-----------+-------------------------------------+
      | outvolts | int16     | Output Volts on Bus                 |
      +----------+-----------+-------------------------------------+
      | maxvolts | int16     | Max volts                           |
      +----------+-----------+-------------------------------------+
      | chvolts  | int16     | Caution high voltage                |
      +----------+-----------+-------------------------------------+
      | clvolts  | int16     | Caution low voltage                 |
      +----------+-----------+-------------------------------------+
      | minvolts | int16     | Minimum low voltage                 |
      +----------+-----------+-------------------------------------+
      | label    | *(OCTET)  | Label for BUS Message (System/Item) |
      +----------+-----------+-------------------------------------+

                      Table 36: BUS Parameter Format

   Table 37, below, shows the values defined in the ecb-state
   Dictionary.  These options represent the Electronic circuit breaker
   status.














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        +==========+=======+======================================+
        | Name     | Value | Definition                           |
        +==========+=======+======================================+
        | UNKNOWN  | %d0   | Circuit is in an unknown condition   |
        +----------+-------+--------------------------------------+
        | OFF      | %d1   | Circuit is turned off                |
        +----------+-------+--------------------------------------+
        | ON       | %d2   | Circuit is turned on                 |
        +----------+-------+--------------------------------------+
        | UNDERCUR | %d3   | Circuit is on, <100ma current drawn  |
        +----------+-------+--------------------------------------+
        | RESET    | %d4   | Request Reset                        |
        +----------+-------+--------------------------------------+
        | FORWARD  | %d5   | ECB is active logical FWD direction  |
        +----------+-------+--------------------------------------+
        | REVERSE  | %d6   | ECB is active logical REV direction  |
        +----------+-------+--------------------------------------+
        | TARGET   | %d7   | ECB is set by target, not ON/OFF     |
        +----------+-------+--------------------------------------+
        | BRAKELOW | %d8   | ECB is set by target, not ON/OFF     |
        +----------+-------+--------------------------------------+
        | SHORTED  | %d128 | Short Circuit                        |
        +----------+-------+--------------------------------------+
        | OVERCUR  | %d129 | Overcurrent (but not short circuit)  |
        +----------+-------+--------------------------------------+
        | OVERVOL  | %d130 | Overvoltage situation                |
        +----------+-------+--------------------------------------+
        | DISABLED | %d131 | Disabled by state-fault              |
        +----------+-------+--------------------------------------+
        | RUNAWAY  | %d132 | Disabled due to runaway (trim/flaps) |
        +----------+-------+--------------------------------------+
        | COLLARED | %d133 | Should not reset in flight           |
        +----------+-------+--------------------------------------+
        | JAMMED   | %d134 | Mechanical Jam detected              |
        +----------+-------+--------------------------------------+
        | PULLED   | %d135 | Pulled                               |
        +----------+-------+--------------------------------------+
        | BACKFLOW | %d136 | Disabled due to reverse current flow |
        +----------+-------+--------------------------------------+

                       Table 37: ecb-state Dictionary

   Table 38, below, shows the values defined in the ecb-flag Dictionary.
   These options represent the Electronic circuit breaker parameter
   flags.






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            +============+=======+============================+
            | Name       | Value | Definition                 |
            +============+=======+============================+
            | INPUTVOLTS | %x01  | Input Volts field is valid |
            +------------+-------+----------------------------+

                       Table 38: ecb-flag Dictionary

4.3.9.  RANGE Parameter Format

   Range description format

   Parameter Identifier: %d11

   Length: 36

   Structure:

       +===========+=============+=================================+
       | Item      | Type        | Description                     |
       +===========+=============+=================================+
       | numticks  | uint16      | How many ticks are there        |
       +-----------+-------------+---------------------------------+
       | dispunits | param-units | Specifier for units for display |
       +-----------+-------------+---------------------------------+
       | minval    | int32       | Minimum valid value             |
       +-----------+-------------+---------------------------------+
       | maxval    | int32       | Maximum valid value             |
       +-----------+-------------+---------------------------------+
       | mindisp   | int32       | Where display starts (values    |
       |           |             | lower than this are clipped)    |
       +-----------+-------------+---------------------------------+
       | maxdisp   | int32       | Where display stops (values     |
       |           |             | higher tha this are clipped)    |
       +-----------+-------------+---------------------------------+
       | ticks     | starray     | Actual tick data                |
       +-----------+-------------+---------------------------------+

                      Table 39: RANGE Parameter Format

   Table 40, below, shows the values defined in the param-units
   Dictionary.  These options represent the Units for the encoding and
   translation of XFS parameters.








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   +========+=========+===============================================+
   | Name   | Value   | Definition                                    |
   +========+=========+===============================================+
   | UNSPEC | %x00    | Units not specified                           |
   +--------+---------+-----------------------------------------------+
   | INHG   | %x00.01 | Use inches of Hg for BARO/MANPRES             |
   +--------+---------+-----------------------------------------------+
   | FT     | %x00.02 | Use feet for altitude                         |
   +--------+---------+-----------------------------------------------+
   | NM     | %x00.03 | Use nautical miles for distance               |
   +--------+---------+-----------------------------------------------+
   | C      | %x00.04 | Use celcius for temperature                   |
   +--------+---------+-----------------------------------------------+
   | LBFT   | %x00.05 | Use pound-feet for torque                     |
   +--------+---------+-----------------------------------------------+
   | S      | %x00.06 | Use seconds for time                          |
   +--------+---------+-----------------------------------------------+
   | A      | %x00.07 | Use amps for current                          |
   +--------+---------+-----------------------------------------------+
   | V      | %x00.08 | Use volts for voltage                         |
   +--------+---------+-----------------------------------------------+
   | LB     | %x00.09 | Use pounds for weight                         |
   +--------+---------+-----------------------------------------------+
   | IN     | %x00.0a | Use inches for distance                       |
   +--------+---------+-----------------------------------------------+
   | FPM    | %x00.0b | Use feet per minute for rate of climb/descent |
   +--------+---------+-----------------------------------------------+
   | LBPH   | %x00.0c | Pounds per Hour for fuel flow                 |
   +--------+---------+-----------------------------------------------+
   | DEGPS  | %x00.0d | Degrees per second for attitude change        |
   +--------+---------+-----------------------------------------------+
   | DEG    | %x00.0e | Degrees for attitude                          |
   +--------+---------+-----------------------------------------------+
   | G      | %x00.0f | G force for load                              |
   +--------+---------+-----------------------------------------------+
   | RGBA   | %x00.10 | 8888 RGBA Value                               |
   +--------+---------+-----------------------------------------------+
   | MHZ    | %x00.11 | Megahertz for Frequency                       |
   +--------+---------+-----------------------------------------------+
   | PCENT  | %x00.12 | Percent of Maximum                            |
   +--------+---------+-----------------------------------------------+
   | KT     | %x00.13 | Knots for Speed                               |
   +--------+---------+-----------------------------------------------+
   | NMPLB  | %x00.14 | Nautical Miles per Pound                      |
   +--------+---------+-----------------------------------------------+
   | KTPS   | %x00.15 | Knots per second                              |
   +--------+---------+-----------------------------------------------+
   | MACH   | %x00.16 | Speed of sound                                |



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   +--------+---------+-----------------------------------------------+
   | CPM    | %x00.17 | Count per minute                              |
   +--------+---------+-----------------------------------------------+
   | PPM    | %x00.18 | Parts per million                             |
   +--------+---------+-----------------------------------------------+
   | LPM    | %x00.19 | Liters Per Minute                             |
   +--------+---------+-----------------------------------------------+
   | KW     | %x00.1a | Kilowatt                                      |
   +--------+---------+-----------------------------------------------+
   | AH     | %x00.1b | Amp Hour                                      |
   +--------+---------+-----------------------------------------------+
   | GAL    | %x00.1c | Gallons of volume                             |
   +--------+---------+-----------------------------------------------+
   | NMPGAL | %x00.1d | Nautical Miles per Gallon                     |
   +--------+---------+-----------------------------------------------+
   | GPH    | %x00.1e | Gallons per Hour for fuel flow                |
   +--------+---------+-----------------------------------------------+
   | MEMS   | %x00.1f | Mantissa/Exponent Milliseconds (2^E)*(M+16)   |
   +--------+---------+-----------------------------------------------+
   | HPA    | %x80.01 | Use Hecto pascals for BARO                    |
   +--------+---------+-----------------------------------------------+
   | M      | %x80.02 | Use meters for altitude                       |
   +--------+---------+-----------------------------------------------+
   | SM     | %x80.03 | Use statute miles for distance                |
   +--------+---------+-----------------------------------------------+
   | F      | %x80.04 | Use fahrenheit for temperature                |
   +--------+---------+-----------------------------------------------+
   | NWM    | %x80.05 | Use Newton Meters for torque                  |
   +--------+---------+-----------------------------------------------+
   | PSI    | %x80.06 | Use PSI for MANPRES                           |
   +--------+---------+-----------------------------------------------+
   | MPH    | %x80.07 | Use miles per hour for speed                  |
   +--------+---------+-----------------------------------------------+
   | SMPLB  | %x80.08 | Statute Miles per Pound                       |
   +--------+---------+-----------------------------------------------+
   | MIN    | %x80.09 | Minutes                                       |
   +--------+---------+-----------------------------------------------+
   | HR     | %x80.0a | Hours                                         |
   +--------+---------+-----------------------------------------------+
   | HP     | %x80.0b | Use Horsepower for power                      |
   +--------+---------+-----------------------------------------------+
   | KG     | %x80.0c | Use kilograms at earth gravity for weight     |
   +--------+---------+-----------------------------------------------+
   | L      | %x80.1c | Liters of volume                              |
   +--------+---------+-----------------------------------------------+
   | LPH    | %x00.1e | Liters per Hour for fuel flow                 |
   +--------+---------+-----------------------------------------------+
   | UL     | %xff.ff | Unitless                                      |



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   +--------+---------+-----------------------------------------------+

                     Table 40: param-units Dictionary

4.3.10.  GPIO Parameter Format

   GPIO summary format

   Parameter Identifier: %d12

   Length: 12

   Structure:

    +==========+========+============================================+
    | Item     | Type   | Description                                |
    +==========+========+============================================+
    | features | uint32 | 4-bit Feature (XFS_GPIO_FEATURE_*) x 8     |
    +----------+--------+--------------------------------------------+
    | outmodes | uint32 | 4-bit Output modes (XFS_GPIO_OUTPUT_*) x 8 |
    +----------+--------+--------------------------------------------+
    | inmodes  | uint16 | 2-bit Input modes (XFS_GPIO_INPUT_*) x 8   |
    +----------+--------+--------------------------------------------+
    | flags    | uint16 | Reserved for future use                    |
    +----------+--------+--------------------------------------------+

                     Table 41: GPIO Parameter Format

4.3.11.  APP Parameter Format

   APP status format

   Parameter Identifier: %d13

   Length: length(data) + 52

   Structure:














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    +============+==============+=====================================+
    | Item       | Type         | Description                         |
    +============+==============+=====================================+
    | state      | scb-state    | State of application*               |
    +------------+--------------+-------------------------------------+
    | rsvd       | uint8        | Reserved bits                       |
    +------------+--------------+-------------------------------------+
    | appflags   | scb-flag     | Flags regarding app                 |
    +------------+--------------+-------------------------------------+
    | avgcpu     | uint16       | Average OS CPU time utilization (of |
    |            |              | allocated amount) over last second  |
    |            |              | (0=unknown, 1=minimal, 65535=all)   |
    +------------+--------------+-------------------------------------+
    | hwcpu      | uint16       | High water OS CPU time utilization  |
    |            |              | (of allocated amount, 0=unknown,    |
    |            |              | 1=minimal, 65535=all)               |
    +------------+--------------+-------------------------------------+
    | stackused  | uint16       | Portion of stack used (0=unknown,   |
    |            |              | 1=minimal, 65535=all)               |
    +------------+--------------+-------------------------------------+
    | heapused   | uint16       | Portion of heap used (0=unknown,    |
    |            |              | 1=minimal, 65535=all)               |
    +------------+--------------+-------------------------------------+
    | netused    | uint16       | Portion of network used (0=unknown, |
    |            |              | 1=minimal, 65535=all)               |
    +------------+--------------+-------------------------------------+
    | otherused  | uint16       | Worst case portion of any other     |
    |            |              | limited resources (0=unknown,       |
    |            |              | 1=minimal, 65535=all)               |
    +------------+--------------+-------------------------------------+
    | ivcsw      | uint32       | Involuntary context switches        |
    +------------+--------------+-------------------------------------+
    | aircraftid | 16*16(OCTET) | Aircraft Identifier                 |
    +------------+--------------+-------------------------------------+
    | swrev      | 16*16(OCTET) | Software Version Identifier         |
    +------------+--------------+-------------------------------------+
    | label      | *(OCTET)     | Name of APP                         |
    +------------+--------------+-------------------------------------+

                       Table 42: APP Parameter Format

   Table 43, below, shows the values defined in the scb-state
   Dictionary.  These options represent the Software circuit breaker
   states.







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    +===========+=======+============================================+
    | Name      | Value | Definition                                 |
    +===========+=======+============================================+
    | UNKNOWN   | %d0   | State of software is unknown               |
    +-----------+-------+--------------------------------------------+
    | STARTING  | %d1   | Application is in startup phase            |
    +-----------+-------+--------------------------------------------+
    | RUNNING   | %d2   | Application is running                     |
    +-----------+-------+--------------------------------------------+
    | STOPPING  | %d3   | Stopping has been requested                |
    +-----------+-------+--------------------------------------------+
    | RESTART   | %d4   | Restart Application (PULL + RESET + START) |
    +-----------+-------+--------------------------------------------+
    | RESET     | %d5   | Allow application to be started            |
    +-----------+-------+--------------------------------------------+
    | HUNG      | %d6   | Application is running but is no longer    |
    |           |       | responsive                                 |
    +-----------+-------+--------------------------------------------+
    | DEGRADED  | %d127 | Application is running in a degraded mode  |
    +-----------+-------+--------------------------------------------+
    | STOPPED   | %d128 | Application is stopped                     |
    +-----------+-------+--------------------------------------------+
    | STARTFAIL | %d129 | Application failed startup                 |
    +-----------+-------+--------------------------------------------+
    | RUNAWAY   | %d130 | Application has a runaway loop             |
    +-----------+-------+--------------------------------------------+
    | OVERCPU   | %d131 | Application is using excessive CPU while   |
    |           |       | in RUNNING state                           |
    +-----------+-------+--------------------------------------------+
    | OVERMEM   | %d132 | Application terminated due to memory       |
    |           |       | overrun                                    |
    +-----------+-------+--------------------------------------------+
    | EXCEPTION | %d133 | Application terminated due to runtime      |
    |           |       | exception                                  |
    +-----------+-------+--------------------------------------------+
    | ENDED     | %d134 | Application ended without error or request |
    +-----------+-------+--------------------------------------------+
    | ENDERROR  | %d135 | Application ended with error condition     |
    +-----------+-------+--------------------------------------------+
    | PULLED    | %d136 | Application should not be allowed to run   |
    |           |       | until reset                                |
    +-----------+-------+--------------------------------------------+
    | COLLARED  | %d137 | Should not reset in flight                 |
    +-----------+-------+--------------------------------------------+

                      Table 43: scb-state Dictionary





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   Table 44, below, shows the values defined in the scb-flag Dictionary.
   These options represent the Software Circuit Breaker Flags.

     +=========+=======+=============================================+
     | Name    | Value | Definition                                  |
     +=========+=======+=============================================+
     | NONE    | %d0   | Application running within normal paramters |
     +---------+-------+---------------------------------------------+
     | HIGHMEM | %x01  | Application has used unexpectedly high      |
     |         |       | portion of memory                           |
     +---------+-------+---------------------------------------------+
     | HIGHCPU | %x02  | Application has used unexpectedly high      |
     |         |       | portion of CPU                              |
     +---------+-------+---------------------------------------------+
     | HIGHBW  | %x04  | Application has used unexpectedly high      |
     |         |       | portion of network bandwidth                |
     +---------+-------+---------------------------------------------+

                       Table 44: scb-flag Dictionary

4.3.12.  UPDATE Parameter Format

   Aircraft Update Progress

   Parameter Identifier: %d15

   Length: length(data) + 56

   Structure:

        +============+======================+=====================+
        | Item       | Type                 | Description         |
        +============+======================+=====================+
        | aircraftid | 16*16(OCTET)         | Aircraft Identifier |
        +------------+----------------------+---------------------+
        | progress   | uint32               | Progress            |
        +------------+----------------------+---------------------+
        | progflags  | msg-cmd-updstat-flag | Progress Flags      |
        +------------+----------------------+---------------------+
        | activity   | 32*32(OCTET)         | Description of      |
        |            |                      | current activity    |
        +------------+----------------------+---------------------+
        | label      | *(OCTET)             | Name of CPU being   |
        |            |                      | updated             |
        +------------+----------------------+---------------------+

                     Table 45: UPDATE Parameter Format




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   Table 46, below, shows the values defined in the msg-cmd-updstat-flag
   Dictionary.  These options represent the Maintenance mode status
   update flags.

          +=========+=======+===================================+
          | Name    | Value | Definition                        |
          +=========+=======+===================================+
          | SUCCESS | %x01  | Update is complete and successful |
          +---------+-------+-----------------------------------+
          | ERROR   | %x02  | Error during update               |
          +---------+-------+-----------------------------------+

                 Table 46: msg-cmd-updstat-flag Dictionary

4.3.13.  SERVO Parameter Format

   Position with flags to interpret whether servo should be engaged,
   disengaged or left alone and whether active

   Parameter Identifier: %d16

   Length: 8

   Structure:

                 +===========+============+=============+
                 | Item      | Type       | Description |
                 +===========+============+=============+
                 | servopos  | int32      | None        |
                 +-----------+------------+-------------+
                 | servomode | afcs-servo | None        |
                 +-----------+------------+-------------+

                     Table 47: SERVO Parameter Format

   Table 48, below, shows the values defined in the afcs-servo
   Dictionary.  These options represent the Servo engagement flags.














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      +============+===============+===============================+
      | Name       | Value         | Definition                    |
      +============+===============+===============================+
      | ENGAGE     | %x80.00.00.00 | If present in engagement      |
      |            |               | request, along with 'ENGAGED' |
      |            |               | value, set engagment status   |
      +------------+---------------+-------------------------------+
      | ENGAGED    | %d1           | For requests, retain current  |
      |            |               | engagement state, for status, |
      |            |               | present if currently engaged  |
      +------------+---------------+-------------------------------+
      | DISENGAGED | %d0           | If engaged, disengage and for |
      |            |               | status, currently disengaged  |
      +------------+---------------+-------------------------------+

                     Table 48: afcs-servo Dictionary

4.3.14.  DBASE Parameter Format

   Database Information

   Parameter Identifier: %d17

   Length: 92

   Structure:

      +==========+==============+===================================+
      | Item     | Type         | Description                       |
      +==========+==============+===================================+
      | crc      | uint32       | 32-bit CRC of database file       |
      +----------+--------------+-----------------------------------+
      | name     | 16*16(OCTET) | Name of database (e.g. com)       |
      +----------+--------------+-----------------------------------+
      | supplier | 16*16(OCTET) | Who supplied the database         |
      +----------+--------------+-----------------------------------+
      | region   | 16*16(OCTET) | What region is the data valid for |
      +----------+--------------+-----------------------------------+
      | cycle    | 16*16(OCTET) | What cycle                        |
      +----------+--------------+-----------------------------------+
      | valid    | 12*12(OCTET) | What data begins data validity    |
      |          |              | YYYY-MM-DD                        |
      +----------+--------------+-----------------------------------+
      | expires  | 12*12(OCTET) | After which data is data expired  |
      |          |              | YYYY-MM-DD                        |
      +----------+--------------+-----------------------------------+

                      Table 49: DBASE Parameter Format



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4.3.15.  DATETIME Parameter Format

   Date and Time with internal values normalized to be consistent

   Parameter Identifier: %d18

   Length: 20

   Structure:

   +==========+=========+=============================================+
   | Item     | Type    | Description                                 |
   +==========+=========+=============================================+
   | epochsec | uint32  | Number of seconds since the epoch of Jan 1, |
   |          |         | 2025 or zero for dates predating the epoch, |
   |          |         | without consideration of leap seconds       |
   +----------+---------+---------------------------------------------+
   | timems   | uint32  | Number of milliseconds since midnight       |
   +----------+---------+---------------------------------------------+
   | flags    | uint16  | Reserved time-related Flags                 |
   +----------+---------+---------------------------------------------+
   | year     | int16   | Year                                        |
   +----------+---------+---------------------------------------------+
   | yday     | uint16  | Day of year beginning with 1                |
   +----------+---------+---------------------------------------------+
   | mon      | month   | Month of year                               |
   +----------+---------+---------------------------------------------+
   | mday     | uint8   | Day of month beginning with 1               |
   +----------+---------+---------------------------------------------+
   | wday     | weekday | Day of week                                 |
   +----------+---------+---------------------------------------------+
   | hour     | uint8   | Number of whole hours since midnight        |
   +----------+---------+---------------------------------------------+
   | min      | uint8   | Number of whole minutes past the most       |
   |          |         | recent whole hour                           |
   +----------+---------+---------------------------------------------+
   | sec      | uint8   | Number of whole seconds past the most       |
   |          |         | recent whole minute with 60 used for a leap |
   |          |         | second                                      |
   +----------+---------+---------------------------------------------+

                   Table 50: DATETIME Parameter Format

   Table 51, below, shows the values defined in the month Dictionary.
   These options represent the Months of the year.






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                       +======+=======+============+
                       | Name | Value | Definition |
                       +======+=======+============+
                       | JAN  | %d0   | January    |
                       +------+-------+------------+
                       | FEB  | %d1   | February   |
                       +------+-------+------------+
                       | MAR  | %d2   | March      |
                       +------+-------+------------+
                       | APR  | %d3   | April      |
                       +------+-------+------------+
                       | MAY  | %d4   | May        |
                       +------+-------+------------+
                       | JUN  | %d5   | June       |
                       +------+-------+------------+
                       | JUL  | %d6   | July       |
                       +------+-------+------------+
                       | AUG  | %d7   | August     |
                       +------+-------+------------+
                       | SEP  | %d8   | September  |
                       +------+-------+------------+
                       | OCT  | %d9   | October    |
                       +------+-------+------------+
                       | NOV  | %d10  | November   |
                       +------+-------+------------+
                       | DEC  | %d11  | December   |
                       +------+-------+------------+

                         Table 51: month Dictionary

   Table 52, below, shows the values defined in the weekday Dictionary.
   These options represent the Days of the week.



















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                       +======+=======+============+
                       | Name | Value | Definition |
                       +======+=======+============+
                       | SUN  | %d0   | Sunday     |
                       +------+-------+------------+
                       | MON  | %d1   | Monday     |
                       +------+-------+------------+
                       | TUE  | %d2   | Tuesday    |
                       +------+-------+------------+
                       | WED  | %d3   | Wednesday  |
                       +------+-------+------------+
                       | THU  | %d4   | Thursday   |
                       +------+-------+------------+
                       | FRI  | %d5   | Friday     |
                       +------+-------+------------+
                       | SAT  | %d6   | Saturday   |
                       +------+-------+------------+

                        Table 52: weekday Dictionary

4.4.  Native Structures

4.4.1.  Structures

   This section defines the default structures that are used for
   translating between XSEDE and other protocol interfaces.

4.4.1.1.  config-entry-hdr-structure

      rlen(2 bytes): Record Length
      flags(2 bytes): Record Flags
      dtype(2 bytes): Data Type

4.4.1.2.  msg-cmd-mxreq-structure

      cpu(32 bytes): CPU for which maintenance mode is being requested
      aircraftid(16 bytes): Aircraft ID for which MX mode is being
      requested

4.4.1.3.  msg-cmd-updreq-structure

      cpu(32 bytes): CPU for which maintenance mode is being requested
      aircraftid(16 bytes): Aircraft ID for which MX mode is being
      requested
      tftpserver(4 bytes): TFTP Server IP Address

4.4.1.4.  msg-cmd-diagreq-structure




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      cpu(32 bytes): CPU for which maintenance mode is being requested
      aircraftid(16 bytes): Aircraft ID for which MX mode is being
      requested
      tftpserver(4 bytes): TFTP Server IP Address for results
      diag(32 bytes): Requested Diagnostic Name

4.4.1.5.  msg-cmd-mxchal-structure

      cpu(32 bytes): CPU for which maintenance mode authentication is
      being requested
      aircraftid(16 bytes): Aircraft ID for which MX mode is being
      requested
      salt(32 bytes): Salt which must be signed

4.4.1.6.  msg-cmd-mxauth-structure

      cpu(32 bytes): CPU for which maintenance mode authentication is
      being requested
      aircraftid(16 bytes): Aircraft ID for which MX mode is being
      requested
      salt(32 bytes): Salt which must be signed
      sig(64 bytes): Signed SHA1 signature of cpu ^ salt ^ aircraftid

4.4.1.7.  msg-cmd-updstat-structure

      cpu(32 bytes): CPU for which maintenance mode is being requested
      aircraftid(16 bytes): Aircraft ID for which MX mode is being
      requested
      activity(32 bytes): Description of current activity
      progress(4 bytes): Progress in 1/1000 of one percent
      progflags(4 bytes): Flags for progress status

4.4.1.8.  msg-sub-msg-structure

      mclass(1 bytes): Message Class
      mclid(1 bytes): Class Specific Message ID (or 0 for any message id
      for the given class)
      rsvd(2 bytes): Reserved for future use

4.4.1.9.  suip-frame-structure

      cmd(2 bytes): Command
      addr(2 bytes): Peripheral Address
      data(variable-size bytes): Data

4.4.1.10.  cantun-rxdata-structure

      seqno(2 bytes): None



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      data(1 bytes): None

4.4.1.11.  cantun-txstatus-structure

      flags(2 bytes): None

4.4.1.12.  cantun-rxstatus-structure

      rxseqno(2 bytes): Last Received sequence number (0-16383), if high
      bit is 1, message is from perspective of CPU
      txseqno(2 bytes): Next to transmit sequence number (0-16383)
      lastrx(2 bytes): Time since last received message (0-65535)
      rxmiss(2 bytes): Count of sequence mismatches (0-65535)

4.4.1.13.  cantun-txdata-structure

      seqno(2 bytes): When transmitting, the top two bits are reserved
      for beginning and end bits to be sure whole messages are
      transferred
      data(1 bytes): None

4.4.1.14.  cantun-txflags-health-structure

      seqno(2 bytes): None
      status(1 bytes): Aircraft Status
      data(1 bytes): None

4.4.1.15.  cantun-rxflags-health-structure

      seqno(2 bytes): None
      volts(2 bytes): Input Voltage
      temp(1 bytes): Temperature in degrees C relative to -80C

4.4.1.16.  cantun-rxflags-ecb-structure

      seqno(2 bytes): None
      volts(2 bytes): Volts on Bus in 0.1 volts
      drawamps(2 bytes): Current draw in 0.1 amps on bus
      state(1 bytes): Current state of ECB
      flags(1 bytes): Flags on ECB

4.4.1.17.  cantun-rxstatus-ecb-structure

      nominalamps(2 bytes): Nominal Max Current draw in 0.1 amps on bus
      hardamps(2 bytes): Absolute Max Current draw in 0.1 amps on bus
      nominalrevamps(2 bytes): Nominal reverse max amps
      hardrevamps(2 bytes): Nominal reverse max amps




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4.4.1.18.  cantun-txflags-ecb-structure

      seqno(2 bytes): None
      nominalmaxamps(2 bytes): Nominal max amps
      hardmaxamps(2 bytes): Hard maximum Amps
      state(1 bytes): State
      flags(1 bytes): None

4.4.1.19.  cantun-txdata-ecb-structure

      seqno(2 bytes): None
      posreq(2 bytes): Requested position (0-1000) top 6 bits reserved

4.4.1.20.  cantun-rxdata-ecb-structure

      seqno(2 bytes): None
      posreq(2 bytes): Currently requested position (0-1000) top 6 bits
      reserved
      posact(2 bytes): Actual current position (0-1000) top 6 bits
      reserved

4.4.1.21.  cantun-rxflags-gpio-structure

      seqno(2 bytes): None
      inputmodes(2 bytes): Detected input modes (XFS_GPIO_INPUT_*) (8
      total)
      outputmodes(4 bytes): Each port output mode (XFS_GPIO_OUTPUT_*) (8
      total)

4.4.1.22.  cantun-txflags-gpio-structure

      seqno(2 bytes): None
      isanalog(1 bytes): Which ports we wish to receive analog values?
      isreset(1 bytes): Which ports should have faults reset
      outputmodes(4 bytes): Each port output mode (8 total)

4.4.1.23.  cantun-rxdata-gpio-structure

      seqno(2 bytes): None
      rxdata(2 bytes): Recieved data - Bit 15 if last entry, bits 14-12
      are pin # (0-7), bits 0-11 are value 0-4095, up to 3 entries

4.4.1.24.  cantun-txdata-gpio-structure

      seqno(2 bytes): None
      txdata(2 bytes): Transmitted PWM/DAC value - Bit 15 reserved, bits
      14-12 are pin # (0-7), bits 0-11 are value 0-4095, up to 3 entries




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4.4.1.25.  cantun-rxdata-ar429-structure

      seqno(2 bytes): None
      flags(2 bytes): Reserved
      arinc429(4 bytes): ARINC 429 Word

4.4.1.26.  cantun-txdata-ar429-structure

      seqno(2 bytes): None
      flags(2 bytes): Reserved
      arinc429(4 bytes): ARINC 429 Word

4.4.1.27.  cantun-rxflags-config-structure

      seqno(2 bytes): None
      cmd(1 bytes): None
      flags(1 bytes): None
      moduleid(4 bytes): Globally unique module ID

4.4.1.28.  cantun-txflags-config-structure

      seqno(2 bytes): None
      cmd(1 bytes): None
      flags(1 bytes): None
      moduleid(4 bytes): Globally unique module ID

4.4.1.29.  cantun-txdata-config-structure

      seqno(2 bytes): None
      data(6 bytes): For Console, commands to be issued to device.  For
      Flash, actual flash data

4.4.1.30.  cantun-rxdata-config-structure

      seqno(2 bytes): None
      data(6 bytes): For Console, output from device.  For Flash,
      acknowledge receipt by seqno

4.4.1.31.  ethertun-can-structure

      canid(4 bytes): CAN ID and related fields
      dlc(1 bytes): Length of data (0-8 bytes)
      srcbus(1 bytes): Globally Unique Source Bus Number
      seqno(2 bytes): Sequence Number 0 - 0x3fff
      data(8 bytes): Encapsulated CAN data

4.4.1.32.  ethertun-arinc429-structure




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      srcbus(1 bytes): Globally Unique Source Bus Number
      flags(1 bytes): Flags reserved for future use
      seqno(2 bytes): Sequence Number
      words(4 bytes): Encapsulated ARINC429 data

4.4.1.33.  ethertun-serial-structure

      srcbus(1 bytes): Globally Unique Source Serial Bus Number
      flags(1 bytes): Flags reserved for future use
      seqno(2 bytes): Sequence Number 0 - 0x3fff
      data(variable-size bytes): Encapsulated Serial data

4.4.1.34.  ethertun-gpio-structure

      seqno(2 bytes): Sequence number unique to source IP/PORT combo
      pinno(1 bytes): Pin Number
      outmode(1 bytes): Output modes (XFS_GPIO_OUTPUT_*)
      value(4 bytes): Analog or digital value

4.4.1.35.  ethertun-ts-can-structure

      canid(4 bytes): CAN ID and related fields
      dlc(1 bytes): Length of data (0-8 bytes)
      srcbus(1 bytes): Globally Unique Source Bus Number
      seqno(2 bytes): Sequence Number
      origts(4 bytes): Original Relative Timestamp
      data(8 bytes): Encapsulated CAN data

4.4.1.36.  milstd1553-etherhdr-structure

      flags(2 bytes): Reserved for flags
      seqno(2 bytes): Sequence number of 14 bits

4.4.1.37.  milstd1553-hdr-structure

      flags(2 bytes): Frame Flags
      modecode(1 bytes): Class of message transaction
      wordcount(1 bytes): Number of actual words (0-32)
      rtaddr1(1 bytes): Remote Terminal Address (first cmd)
      subaddr1(1 bytes): Remote Terminal Function Subaddress (first cmd)
      status1(2 bytes): Remote Terminal Status (first cmd)
      rtaddr2(1 bytes): Remote Terminal Address (second cmd)
      subaddr2(1 bytes): Remote Terminal Function Subaddress (second
      cmd)
      status2(2 bytes): Remote Terminal Status (second cmd)
      data(2 bytes): 0-32 words of data





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4.4.1.38.  datagram-gpio-msg-structure

      value(4 bytes): Interpreted value of GPIO (e.g. DAC/ADC/PWM)
      outmodes(4 bytes): 4-bit Output modes (XFS_GPIO_OUTPUT_*) x 8
      inmodes(2 bytes): 2-bit Input modes (XFS_GPIO_INPUT_*) x 8

4.4.1.39.  msg-structure

      srcaddr(2 bytes): Identifier of transmitting source, typically
      computer ID in upper 8 bits and microservice ID in lower 8 bits
      mseqno(2 bytes): Sequence number of message.
      mclass(1 bytes): Message Class
      mclid(1 bytes): Message ID
      flags(2 bytes): Message flags, bottom 3 bits reserved for cert
      level
      tcid(2 bytes): If multiple pathways exist for identical data,
      which pathway are we
      len(2 bytes): Length of message in bytes -- note that it could be
      shorter than available data due to alignment issues
      data(variable-size bytes): Data (typically PARAMs)

4.4.1.40.  msg-log-hdr-structure

      relts(4 bytes): Relative timestamp since startup

4.4.1.41.  qar-datagram-log-hdr-structure

      relts(4 bytes): Relative timestamp since startup
      flags(2 bytes): Reserved for potential future flags for packet
      length(2 bytes): Length of packets in bytes

4.4.1.42.  param-common-structure

      unit(2 bytes): If appropriate, which unit this parameter applies
      to (e.g. Engine #1)
      subunit(2 bytes): If appropriate, which subunit this parameter
      applies to (e.g. Engine #2, Cylinder #3)
      ident(4 bytes): XFS Parameter Identifier
      format(1 bytes): Format of data element
      confidence(1 bytes): Confidence of data element
      ttl(1 bytes): Time to live in milliseconds encoded using the MEMS
      encoding
      pflags(1 bytes): Reserved Flags, bottom 3 bits are certification
      level of data

4.4.1.43.  param-range-tick-structure

      flags(2 bytes): Flags if any



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      color(2 bytes): See tick color definition
      value(4 bytes): Value *above* which the tick should apply (except
      blue)
      label(8 bytes): Name associated with label

4.5.  Parameter Ranges

   All parameter attributes values are typed, but some are further
   constrained to certain ranges.  The ranges may limit in both value
   and display purposes.  The display 'ticks' can define various
   classifications such as a green, yellow, or red range.  Furthermore,
   ranges can change over time.  For instance, good oil pressure for a
   cold engine may be normally higher than that for a warm engine and a
   special parameter can be broadcast to indicate a range change.
   Table 39 defines the RANGE parameter format.

   Parameters that have a default range have that range described in the
   next section.  The default range will be displayed in tabular format.
   Many parameters have default and unchangeable ranges, while others
   have dynamic ranges.  Parameters that have dynamic ranges use a
   parameter that only differs in the length portion of the Parameter
   Data Len & Ident attribute.  and having a RANGE attribute as its
   payload.  The receiving node MUST distinguish between the value and
   the range parameters by examining the length portion of the
   parameter's attribute.  Should a parameter attribute value be outside
   the permitted range. the value MUST be ignored.

   In the style of the next section, a generic range parameter is
   defined below:

4.5.1.  Sample Range Parameter

      Parameter ID: Same as main parameter.
      Unit Usage: Same as main parameter.
      SubUnit Usage: Same as main parameter.
      Length: RANGE Length - 24 decimal plus tick data length.
      Format: RANGE (See Table 39.)

4.5.2.  Ranges

   This section defines the default attribute ranges that are used in
   XSEDE.

4.5.2.1.  SERVO Range Default

      Minimum Value: -100000
      Maximum Value: 100000
      Minimum Display Value: -100000



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      Maximum Display Value: 100000
      Divisor: 1000

4.5.2.2.  ROLL Range Default

      Minimum Value: -18000
      Maximum Value: 17999
      Minimum Display Value: -18000
      Maximum Display Value: 17999
      Divisor: 100

4.5.2.3.  PITCH Range Default

      Minimum Value: -9000
      Maximum Value: 8999
      Minimum Display Value: -9000
      Maximum Display Value: 9000
      Divisor: 100

4.5.2.4.  PERCENT Range Default

      Minimum Value: 0
      Maximum Value: 100
      Minimum Display Value: 0
      Maximum Display Value: 100
      Divisor: 1

4.5.2.5.  THOUPERCENT Range Default

      Minimum Value: 0
      Maximum Value: 100000
      Minimum Display Value: 0
      Maximum Display Value: 100000
      Divisor: 100

4.5.2.6.  HDG Range Default

      Minimum Value: 100
      Maximum Value: 36099
      Minimum Display Value: 1
      Maximum Display Value: 36000
      Divisor: 100

4.5.2.7.  OBS Range Default

      Minimum Value: 1000
      Maximum Value: 360000
      Minimum Display Value: 0



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      Maximum Display Value: 360000
      Divisor: 1000

4.5.2.8.  DEVIATION Range Default

      Minimum Value: -1000
      Maximum Value: 1000
      Minimum Display Value: -1000
      Maximum Display Value: 1000
      Divisor: 1

4.5.2.9.  FLAPS Range Default

      Minimum Value: -1000
      Maximum Value: 1000
      Minimum Display Value: -1000
      Maximum Display Value: 1000
      Divisor: 1

4.5.2.10.  BRIGHTNESS Range Default

      Minimum Value: 0
      Maximum Value: 2000
      Minimum Display Value: 0
      Maximum Display Value: 2000
      Divisor: 1

4.5.2.11.  COMFREQ Range Default

      Minimum Value: 11800000
      Maximum Value: 13699999
      Minimum Display Value: 11800000
      Maximum Display Value: 13699999
      Divisor: 100000

4.5.2.12.  NAVFREQ Range Default

      Minimum Value: 10800000
      Maximum Value: 11799999
      Minimum Display Value: 10800000
      Maximum Display Value: 11799999
      Divisor: 100000









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4.6.  Dictionary Types

   This section declares the initial set of XSEDE dictionaries.  Each
   dictionary is defined by a name and short definition.  It contains a
   set of entries that represent the name value mappings of the
   dictionary.  There are some primitive dictionaries without entries
   that specify the format of the data (i.e. octal or hex)

4.6.1.  numbersok - Options for whether bare numbers are acceptable

      FALSE (0) : Bare numbers are not permitted
      TRUE (1) : Bare numbers are permitted and in output strings are
      represented in decimal form
      OCTAL (2) : Bare numbers are permitted and in output strings are
      represented in octal
      HEX (3) : Bare numbes are permitted and in output strings are
      represented in hexadecimal

4.6.2.  ttl_mems - Convert times to their closest 8-bit mantissa-
        exponent representation

      NEVER (0) : Does not expire
      DEFAULT (256) : Use default value if specified elsewhere

4.6.3.  none - Generic unsigned 32-bit value

4.6.4.  signedval - Generic signed 32-bit value

4.6.5.  hex - Hexadecimal representation

4.6.6.  octal - Octal representation

4.6.7.  component_feature - Flags that specified requested features or
        actions of a component

      REQUEST_TIMESLOT ((1U << 0)) : Request a timeslot (if supported)
      REQUEST_REALTIME ((1U << 1)) : Request hard realtime (if
      supported)
      NEED_CONFIGURE ((1U << 2)) : Component is launching in config mode
      NEED_DUMP ((1U << 3)) : At first run, perform dump instead of
      normal operation
      NEED_FORK ((1U << 4)) : At first run, become a background process
      (if supported)
      NEED_KILL ((1U << 5)) : Kill off a running version of the
      component (if supported)
      SKIP_LOADCONFIG ((1U << 6)) : Skip normal configuration loading
      HAS_TOUCH ((1U << 7)) : Application is running with an active
      touch interface



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      HIDECMDLINE ((1U << 8)) : Hide command line outputs
      NOECHO ((1U << 9)) : Disable echo of received characters

4.6.8.  component_debug - Component debugging flags

      RXDUMP ((1U << 0)) : Enable dumping of received messages from the
      XFS Bus by this component
      TXDUMP ((1U << 1)) : Enable dumping of messages transmitted to the
      XFS Bus from this component

4.6.9.  agg_feature - Features associated with aggregated applications

      NONE (0) : No selected features
      PULLED ((1 << 0)) : Pulled
      COLLARED ((1 << 1)) : Should not be reset in flight
      AUTOSTART ((1 << 2)) : Automatically start on reboot if not
      pulled/collared
      AUTORESET ((1 << 3)) : Reset from pulled or tripped state on reset

4.6.10.  canid - CAN ID special flags and numbers

      EFF ((1U << 31)) : Extended Frame Flag
      RTR ((1U << 30)) : Remote Transmission Request
      ERR ((1U << 29)) : Error Message

4.6.11.  msg_cmd_updstat_flag - Maintenance mode status update flags

      SUCCESS ((1U << 0)) : Update is complete and successful
      ERROR ((1U << 1)) : Error during update

4.6.12.  mm_apt_layer - Types of airports to display within layering of
         airport information

      PRIVATE ((1U << 0)) : Display private airports
      WATER ((1U << 1)) : Display sea ports
      HELI ((1U << 2)) : Display heliports
      MILITARY ((1U << 3)) : Display military airfields

4.6.13.  mm_tlayer - Topology, raster and related static mapping layers

      NONE (0) : No Layers Enabled
      TOPO ((1U << 0)) : Topography
      TERRAIN ((1U << 1)) : Terrain warnings
      OBSTACLES ((1U << 2)) : Obstacles
      TRAFFIC ((1U << 3)) : Traffic
      VFR ((1U << 4)) : VFR Chart
      LOALT ((1U << 5)) : Low Altitude IFR
      HIALT ((1U << 6)) : High Altitude IFR



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      CALLSIGNS ((1U << 7)) : Traffic Callsigns
      VORS ((1U << 8)) : VOR Stations
      FIXES ((1U << 9)) : RNAV Fixes
      WATER ((1U << 10)) : Detailed Water

4.6.14.  mm_wlayer - Dynamic weather layers for maps

      NONE (0) : No Layers Enabled
      NEXRAD ((1U << 0)) : NEXRAD Radar Overlay
      WIND ((1U << 1)) : Wind Data
      LIGHTNING ((1U << 2)) : Lightning Overlay
      ICING ((1U << 3)) : Icing Forecast
      TURB ((1U << 4)) : Turbulence Forecast
      CLOUDS ((1U << 5)) : Cloud Tops Forecast

4.6.15.  mm_alayer - DO-358A AIRMET and SIGMET layers for mapping

      NONE (0) : No Layers Enabled
      TFR ((1U << 0)) : Temporary Flight Restriction
      TURB ((1U << 1)) : Turbulence
      LLWS ((1U << 2)) : Low Level Wind Shear
      SFC ((1U << 3)) : Strong Surface Winds
      ICING ((1U << 4)) : Icing Conditions
      FRZLVL ((1U << 5)) : Lowest Freezing Level
      IFR ((1U << 6)) : Instrument Flight Conditions
      MTN ((1U << 7)) : Mountain Obscuration
      CONVSIG ((1U << 17)) : Convective Sigmet

4.6.16.  mm_param - Parameters for rendering of moving maps

      SCALE (0x0001) : Map Scale in pixels per degree lat
      CLAT (0x0002) : Center map at this lattitude -- 0x80000000 to
      track aircraft
      CLON (0x0003) : Center map at this longitude -- 0x80000000 to
      track aircraft
      APTLAYER (0x0004) : Bitmask of XFS_MM_APT_LAYER_* for what to
      display
      WIDTH (0x0005) : Width in pixels of map
      HEIGHT (0x0006) : Height in pixels of map
      TLAYERS (0x0007) : Topography/Obstacle/Terrain/Traffic layers
      WLAYERS (0x0008) : Weather Layers layers
      ALTSEL (0x0009) : Altitude sel for Winds etc -- 0x80000000 to
      track current altitude
      ALAYERS (0x000a) : AIRMET/SIGMET layers
      AUTOTRACK (0x80000000) : AutoTrack value for tracking aircraft
      position and altitude





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4.6.17.  efb_param - Parameters for rendering of georeferenced
         procedures

      SCALE (0x0001) : EFB Scale in relative pixels where 1000 is 1:1
      pixel scaling
      CLAT (0x0002) : Center map at this lattitude -- 0x80000000 to
      track aircraft
      CLON (0x0003) : Center map at this longitude -- 0x80000000 to
      track aircraft
      FIXNAME (0x0004) : Name of fix for which information is desired
      WIDTH (0x0005) : Width in pixels of EFB Content
      HEIGHT (0x0006) : Height in pixels of EFB Content
      PAGE (0x0007) : Name of page within EFB
      TARGET (0x0008) : Page specific target within EFB page

4.6.18.  sv_param - Parameters for rendering of synthetic vision

      WIDTH (0x0001) : Width in pixels of view
      HEIGHT (0x0002) : Height in pixels of view

4.6.19.  unit - XFS parameter unit values

      ANY (0xffff) : Any Unit

4.6.20.  unitmask - Mask of unit values

      NONE (0) : No units selected
      1 ((1U << 0)) : Unit 1 selected
      2 ((1U << 1)) : Unit 2 selected
      3 ((1U << 2)) : Unit 3 selected
      4 ((1U << 3)) : Unit 4 selected
      5 ((1U << 4)) : Unit 5 selected
      6 ((1U << 5)) : Unit 6 selected
      7 ((1U << 6)) : Unit 7 selected
      8 ((1U << 7)) : Unit 8 selected
      9 ((1U << 8)) : Unit 9 selected
      10 ((1U << 9)) : Unit 10 selected
      11 ((1U << 10)) : Unit 11 selected
      12 ((1U << 11)) : Unit 12 selected
      13 ((1U << 12)) : Unit 13 selected
      14 ((1U << 13)) : Unit 14 selected
      15 ((1U << 14)) : Unit 15 selected
      16 ((1U << 15)) : Unit 16 selected
      17 ((1U << 16)) : Unit 17 selected
      18 ((1U << 17)) : Unit 18 selected
      19 ((1U << 18)) : Unit 19 selected
      20 ((1U << 19)) : Unit 20 selected
      21 ((1U << 20)) : Unit 21 selected



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      22 ((1U << 21)) : Unit 22 selected
      23 ((1U << 22)) : Unit 23 selected
      24 ((1U << 23)) : Unit 24 selected
      25 ((1U << 24)) : Unit 25 selected
      26 ((1U << 25)) : Unit 26 selected
      27 ((1U << 26)) : Unit 27 selected
      28 ((1U << 27)) : Unit 28 selected
      29 ((1U << 28)) : Unit 29 selected
      30 ((1U << 29)) : Unit 30 selected
      31 ((1U << 30)) : Unit 31 selected
      32 ((1U << 31)) : Unit 32 selected

4.6.21.  subunit - XFS parameter subunit values

      ANY (0xffff) : Any Subunit

4.6.22.  preset - XFS Preset Frequency

      MANUAL (0) : Manual Tuning (no preset)
      LAST (0xfffe) : Last selected frequency

4.6.23.  tcid - XFS transcoder ID values

      NONE (0) : No transcoder ID is required or asserted
      DEFAULT (65536) : Pseudo-value to represent global default

4.6.24.  suip_id - SUIP Identifier

      NONE (0) : No SUIP ID for the actuator
      TOUCH (0xffff) : SUIP Via Touch

4.6.25.  boolean - Nominal boolean values

      FALSE (0) : False
      TRUE (1) : True

4.6.26.  ruleresult - Return values for XFS rules

      CLEAR (0) : Rule evaluates as false
      SET (1) : Rule evaluates as true
      UNKNOWN (-1) : Insufficient information to evaluate rule

4.6.27.  alignment - Horizontal and vertical geometric alignments

      HMASK (0x0f) : Horizontal alignment mask
      HCENTER (0x01) : Horizontally centered
      LEFT (0x02) : Left aligned
      RIGHT (0x03) : Right aligned



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      VMASK (0xf0) : Vertical alignment mask
      VCENTER (0x10) : Vertically centered
      BOTTOM (0x20) : Bottom aligned
      TOP (0x30) : Top aligned

4.6.28.  engstate - States of engines

      UNKNOWN (0x00) : Engine Status Unknown
      OFF (0x01) : Engine is Off
      DRYMOTOR (0x02) : Engine Starting
      STARTING (0x03) : Engine Starting
      RUNNING (0x04) : Engine Running Normally
      FLAMEOUT (0x05) : Engine Flamed Out / Failure
      SHUTDOWN (0x06) : Engine Shutting Down
      SHUTOFF (0x07) : Engine Shut Off
      MODE_MASK (0xff) : Mask for Engine State
      FLAG_IGNITION ((1U << 8)) : Ignition On
      FLAG_FUEL ((1U << 9)) : Fuel Shutoff Open
      FLAG_STARTER ((1U << 10)) : Starter On
      FLAG_GENERATOR ((1U << 11)) : Generator On
      FLAG_BLEED ((1U << 12)) : Bleed Air On
      FLAG_FIRE ((1U << 16)) : Fire Present
      FLAG_EXTINGUISH ((1U << 17)) : Extinguisher Dispensed

4.6.29.  pid_state - States of proportional-integral-derivative control
         logic

      UNKNOWN (0x00) : PID Status Unknown
      SETTLED (0x01) : PID Settled On Desired Value
      CONVERGING (0x02) : PID Oscillating With Decreasing Amplitude
      OSCILLATING (0x03) : PID Oscillating With Constant Amplitude
      DIVERGING (0x04) : PID Oscillating With Increasing Amplitude

4.6.30.  shape - Shapes for use in vector drawings

      NONE (0x00) : No shape
      OVAL (0x01) : Oval Shape
      LINE (0x02) : Line Shape
      TRIANGLE (0x03) : Triangle Shape
      DIAMOND (0x04) : Diamond Shape
      PENTAGON (0x05) : Pentagon Shape
      HEXAGON (0x06) : Hexagon Shape
      SEPTAGON (0x07) : Septagon/Heptagon Shape
      OCTAGON (0x08) : Octagon Shape
      NONAGON (0x09) : Nonagon/Enneagon Shape
      DECAGON (0x0A) : Decagon Shape





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4.6.31.  ldggear - Status of retractable landing gear

      UNKNOWN (0x0000) : Gear Status Unknown
      DOWN (0x0001) : Landing Gear Down
      UP (0x8000) : Landing Gear Up
      FLAG_FAILED ((1U << 16)) : Landing Gear System is Failed

4.6.32.  brake - Status of wheel brakes

      UNKNOWN (0x0000) : Brake Status Unknown
      NONE (0x0001) : Brakes not pressed
      MAX (0x8000) : Max Braking
      PARK ((1U << 16)) : Parking Brake Engaged
      FLAG_FAILED ((1U << 17)) : Brake System is Failed

4.6.33.  ecbunit - ECB unit numbers

      TYPE_MASK (0xf000) : Mask for ECB type flag
      TYPE_ECB (0x0000) : Generic ECB
      TYPE_BUS (0x1000) : Bus
      TYPE_GENALT (0x2000) : Starter/Generator/Alternator
      TYPE_BATT (0x3000) : Battery

4.6.34.  icing_flag - Status of ice detection, anti-ice and deicing
         systems

      ENGINE ((1U << 0)) : Engine Deicing/Anticing On
      AIRFRAME ((1U << 1)) : Airframe Deicing/Anticing On
      INSEP ((1U << 2)) : Inertial Separator Activated
      PITOT ((1U << 3)) : Pitot/Static Heat Activated
      PROPHEAT ((1U << 4)) : Propeller Heat Activated
      WINDHEAT ((1U << 5)) : Windshield Heat Activated
      CARBHEAT ((1U << 6)) : Carb Heat Activated
      CARBICEDET ((1U << 14)) : Carb Icing Detected
      ICEDET ((1U << 15)) : Icing Detected
      ENGINE_FAIL ((1U << 16)) : Engine Deicing/Anticing Failed
      AIRFRAME_FAIL ((1U << 17)) : Airframe Deicing/Anticing Failed
      INSEP_FAIL ((1U << 18)) : Inertial Separator Failed
      PITOT_FAIL ((1U << 19)) : Pitot/Static Heat Failed
      PROPHEAT_FAIL ((1U << 20)) : Propeller Heat Failed
      WINDHEAT_FAIL ((1U << 21)) : Windshield Heat Failed
      CARBHEAT_FAIL ((1U << 22)) : Carb Heat Failed
      CARBICEDET_FAIL ((1U << 30)) : Carb Icing Detection Failed
      ICEDET_FAIL ((1U << 31)) : Icing Detection Failed

4.6.35.  cantun - CAN tunneling 29-bit address special fields

      TUNNEL ((1U << 28)) : Tunneled Data



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      DEVMASK (0xff00000) : Mask for what type of device
      DEV_SERIAL (0x0100000) : RS-232/422/485 Serial Port
      DEV_CONFIG (0x0200000) : Configuration Commands
      DEV_HEALTH (0x0300000) : Health Status
      DEV_AR429 (0x0400000) : ARINC-429
      DEV_MIL1553 (0x0500000) : MIL-STD-1553
      DEV_ECB (0x0600000) : Electronic Circuit Breaker
      DEV_GPIO (0x0700000) : GPIO's
      DEV_CANBUS (0x0800000) : Reserved for possible CAN in CAN
      tunneling
      OPMASK (0xf0000) : Mask for what operation on device
      OPTXMASK (0x10000) : Operation is a transmit operation
      OP_RXDATA (0x00000) : Received from peripheral
      OP_TXDATA (0x10000) : Transmit to peripheral
      OP_RXSTATUS (0x20000) : Status Information Reply
      OP_TXSTATUS (0x30000) : Transmitted Status Information Request
      OP_RXFLAGS (0x40000) : Current received flags + status (48 bits
      total)
      OP_TXFLAGS (0x50000) : Set transmit flags + status (48 bits total)
      SEQNO_FLAG_BEGIN ((1U << 15)) : Beginning of a whole message
      (Transmit)
      SEQNO_FLAG_END ((1U << 14)) : End of a whole message
      SEQNO_MASK (0x3fff) : Max Sequence number

4.6.36.  cantun_cmd - CAN configuration commands

      ACK (0x01) : Or'd with command for response
      DISCOVER (0x02) : Each unit sends a reply with its ID in response
      to a discover
      CONCONSOLE (0x04) : Connect Console
      DISCONSOLE (0x06) : Disconnect Console

4.6.37.  cantun_txstatus_flag - CPU to non-CPU communication of status

      RESETMISS ((1U << 0)) : Reset miss counters
      CPUSEL ((1U << 15)) : Count with respect to CPU

4.6.38.  config_type - XFS configuration file value data types

      SINT (1) : 32-bit signed 2's complement integer
      UINT (2) : 32-bit unsigned integer
      STRING (3) : Optionally null terminated string
      FLOAT (4) : IEEE 754 floating point number
      IPADDR (5) : 32-bit IPv4 IP address
      SIGNATURE (255) : System specific cryptographic signature
      OBJECTBEG (256) : Begin an object definition
      OBJPTRBEG (257) : Begin pointer to an object
      OBJECTSEP (258) : Separates entries in an array



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      OBJECTEND (259) : Ends an entry for an object or object pointer

4.6.39.  config_perm - XFS configuration file value permissions

      MANDATORY ((1U << 16)) : Must be specified
      DELEGATE ((1U << 8)) : Allow delegating permission to level in
      bits 7-0
      VENDOR (200) : Avionics Vendor
      FACTORY (150) : Aircraft Manufacturer
      OWNER (125) : Aircraft Owner
      MAINT (100) : Aircraft Maintenance Facility
      SYSTEM (90) : Saved Aircraft State
      DATA (75) : Navigational Data
      USER (50) : Pilot
      INHERIT (1) : Object parameters inherit from object permission
      UNSET (0) : Permission has not been established

4.6.40.  msg_class - XFS common data bus message classes

      MAINT (2) : Maintenance Message
      OP (3) : Operational Message
      RAW (4) : Access to raw data stream (e.g. RS-232, RS-485, ARINC-
      429, etc)

4.6.41.  ac_status - XFS aircraft state

      GND (0) : Non flight mode
      FLIGHT (1) : Aircraft in flight
      MAINT (2) : Aircraft is in maintenance mode

4.6.42.  msg_op - Message subclasses for operational message class

      SUBFLDATA (1) : Subscribe to Aircraft Flight Data Params
      FLIGHTDATA (2) : Flight Data Info
      DEVSTATUS (3) : Device Status
      GDL90 (4) : GDL-90 Format Messages without framing, FCS or escape
      characters
      SUBMSGCLID (5) : Subscribe to Specific Message Class and ID

4.6.43.  msg_raw - Message subclasses for raw message class

      SERIALRX (1) : Serial raw data stream receive from end device
      SERIALTX (2) : Serial raw data stream transmit to end device
      SPIRX (5) : Raw SPI bus receive from end device
      SPITX (6) : Raw SPI bus transmit to end device
      ARINC429RX (7) : Raw ARINC-429 bus receive from end device
      ARINC429TX (8) : Raw ARINC-429 bus transmit to end device
      MIL1553RX (9) : Raw MIL-STD-1553 received from end device



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      MIL1553TX (10) : Raw MIL-STD-1553 bus transmit to end device
      ECBRX (11) : Raw XFS ECB control receive from end device
      ECBTX (12) : Raw XFS ECB control transmit to end device
      GPIORX (13) : Raw XFS ECB control receive from end device
      GPIOTX (14) : Raw XFS ECB control transmit to end device
      ADCRX (15) : Analog/Digital Converter receive from end device
      DACTX (16) : Digital/Analog Converter transmit to end device
      CANBUSRX (17) : Raw CAN bus receive from end device
      CANBUSTX (18) : Raw CAN bus transmit to end device
      DATAGRAMRX (19) : Raw Datagram receive from end device
      DATAGRAMTX (20) : Raw Datagram transmit to end device

4.6.44.  msg_maint - Message subclasses for maintenance message class

      MXREQ (1) : Request maintenance mode for a specific CPU (or all if
      cpu is empty)
      MXCHAL (2) : Authentication challenge
      MXAUTH (3) : Authentication response
      MXACCEPT (4) : Accept authentication request
      MXDENY (5) : Deny maintenance mode
      MXREADY (6) : Ready for update or diagnostic
      DOUPDATE (7) : User Requests System Update.  Note CPU is requestor
      UPDREQ (8) : Request Update for given Device
      UPDSTAT (9) : Status of Update
      DODIAG (10) : User Requests System Update.  Note CPU is requestor.
      Salt is type of diagnostic.
      DIAGREQ (11) : Request diagnostic for given Device.
      DIAGSTAT (12) : Status of Update

4.6.45.  msg_flag_cert - Message and parameter certification level
         tracking

      EXPERIMENTAL (0) : Experimental
      LEVEL_E (1) : DO-178 Level E
      LEVEL_D (2) : DO-178 Level D
      LEVEL_C (3) : DO-178 Level C
      LEVEL_B (4) : DO-178 Level B
      LEVEL_A (5) : DO-178 Level A

4.6.46.  msg_source_flag - Flags for XFS message sources

      ALWAYSXMIT ((1U << 0)) : Transmit all parameters even if
      confidence is useless
      COPYSELF ((1U << 1)) : Process this message as a received message
      as well
      DEBUGONLY ((1U << 2)) : This message is only used only for
      debugging and not normal operation




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      IMMPREBUF ((1U << 3)) : Immediately prebuffer parameters within
      this message even before transmission

4.6.47.  param_source_flag - Flags for individual parameter sources
         within XFS message sources

      ALWAYSVALID ((1U << 0)) : Parameter source has a fixed value
      TRIGGERXMIT ((1U << 1)) : Candidate for triggering message
      transmission

4.6.48.  param_confidence - XFS common bus parameter format confidence
         levels

      HIGH (100) : Confirmed known value
      USERSEL (90) : User selected value at runtime
      SYSSEL (80) : System selected value at runtime
      UNANIMOUS (50) : Redundant data available and is rationalized
      RATIONAL (40) : Data being rationalized from other data sources
      with normal sources ignored
      VOTED (30) : Data is redundantly verified from identical
      instruments
      SMOOTHED (20) : Smoothed/filtered version of raw data
      RAW (10) : Raw, unchecked data
      ESTIMATE (5) : Rough estimation
      USELESS (0) : Value is missing or expected invalid and supplied
      for debugging ONLY

4.6.49.  endian - CPU endian formats

      HOST (0) : Host Endian Byte Order
      LITTLE (1) : Little Endian Byte Order
      BIG (2) : Big Endian Byte Order

4.6.50.  datagram_direction - Datagram Direction Types

      UNKNOWN (0) : Unknown or unspecified direction type
      SOURCE (1) : We are a source of information for this connection
      DESTINATION (2) : We are a destination of information for this
      connection
      BIDIRECTIONAL (3) : We are both a source and destination of
      information for this connection

4.6.51.  param_units - Units for the encoding and translation of XFS
         parameters

      UNSPEC (0x0) : Units not specified
      INHG (0x0001U) : Use inches of Hg for BARO/MANPRES
      FT (0x0002U) : Use feet for altitude



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      NM (0x0003U) : Use nautical miles for distance
      C (0x0004U) : Use celcius for temperature
      LBFT (0x0005U) : Use pound-feet for torque
      S (0x0006U) : Use seconds for time
      A (0x0007U) : Use amps for current
      V (0x0008U) : Use volts for voltage
      LB (0x0009U) : Use pounds for weight
      IN (0x000aU) : Use inches for distance
      FPM (0x000bU) : Use feet per minute for rate of climb/descent
      LBPH (0x000cU) : Pounds per Hour for fuel flow
      DEGPS (0x000dU) : Degrees per second for attitude change
      DEG (0x000eU) : Degrees for attitude
      G (0x000fU) : G force for load
      RGBA (0x0010U) : 8888 RGBA Value
      MHZ (0x0011U) : Megahertz for Frequency
      PCENT (0x0012U) : Percent of Maximum
      KT (0x0013U) : Knots for Speed
      NMPLB (0x0014U) : Nautical Miles per Pound
      KTPS (0x0015U) : Knots per second
      MACH (0x0016U) : Speed of sound
      CPM (0x0017U) : Count per minute
      PPM (0x0018U) : Parts per million
      LPM (0x0019U) : Liters Per Minute
      KW (0x001aU) : Kilowatt
      AH (0x001bU) : Amp Hour
      GAL (0x001cU) : Gallons of volume
      NMPGAL (0x001dU) : Nautical Miles per Gallon
      GPH (0x001eU) : Gallons per Hour for fuel flow
      MEMS (0x001fU) : Mantissa/Exponent Milliseconds (2^E)*(M+16)
      HPA (0x8001U) : Use Hecto pascals for BARO
      M (0x8002U) : Use meters for altitude
      SM (0x8003U) : Use statute miles for distance
      F (0x8004U) : Use fahrenheit for temperature
      NWM (0x8005U) : Use Newton Meters for torque
      PSI (0x8006U) : Use PSI for MANPRES
      MPH (0x8007U) : Use miles per hour for speed
      SMPLB (0x8008U) : Statute Miles per Pound
      MIN (0x8009U) : Minutes
      HR (0x800aU) : Hours
      HP (0x800bU) : Use Horsepower for power
      KG (0x800cU) : Use kilograms at earth gravity for weight
      L (0x801cU) : Liters of volume
      LPH (0x001eU) : Liters per Hour for fuel flow
      UL (0xffffU) : Unitless

4.6.52.  param_copy_result - Possible return results from copying
         parameters from/to network format




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      SUCCESS (0) : Parameter copied/loaded properly
      UNKNOWN_PARAM ((1U << 0)) : Parameter not known
      UNKNOWN_FORMAT ((1U << 1)) : Parameter format not known
      MISMATCH_FORMAT ((1U << 2)) : Parameter format does not match what
      we expect its format to be
      MISSING ((1U << 3)) : Source of parameter (e.g. config file) is
      missing or empty
      CHKSUMFAIL ((1U << 4)) : Source of parameter had failed checksum
      DESIGNFAIL ((1U << 5)) : Design of parameter system contains an
      error
      IMPROPER_FORMAT ((1U << 6)) : Conversion of parameter from ASCII
      source encountered syntactical error
      UNIMPLEMENTED ((1U << 7)) : This method of copying a parameter is
      not implemented
      POS_NOT_FOUND ((1U << 8)) : Position not found
      IO_ERROR ((1U << 9)) : I/O Error
      SHORT_SRC ((1U << 10)) : Insufficient data in source parameter
      SHORT_DST ((1U << 11)) : Insufficient data in destination
      parameter

4.6.53.  cas_msglvl - Message levels for CAS messages and checklist
         items

      CLEAR (0) : Clear a previously issued CAS message -- issue from
      system only
      DEBUG (1) : In-system debugging output only
      LOG (2) : Log to system log, but do not display
      MAINT (3) : Display only for maintenance purposes
      STATUS (4) : Aircraft system status only
      ADVISORY (5) : Advisory, flight crew should be aware, may require
      later crew response
      CAUTION (6) : Caution, requires immediate flight crew awareness
      and later response
      WARNING (7) : Warning, requires immediate awareness and response.
      COMMENT (10) : Checklist Comment Associated with Previous Item
      UNCHKITEM (11) : Unchecked Checklist Item
      CHKITEM (12) : Checked Checklist Item
      CHKBRANCH (13) : Checklist Branch Choice
      PASS (14) : Built-in Test (BIT) Item passed
      INPROG (15) : Built-in Test (BIT) Item in progress
      NOTREQST (16) : Built-in Test (BIT) Item not yet requested
      INCOMPLT (17) : Built-in Test (BIT) Item test did not complete
      FAIL (18) : Built-in Test (BIT) Item failed

4.6.54.  cas_msgflag - Additional flags associated with CAS messages

      NONE (0) : No additional flags




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      AUTO ((1U << 0)) : Item is automatically checked/unchecked or the
      test is automatically executed

4.6.55.  sched_period - Schedule periods with special meanings

      10MS (10000) : Every task should run at least once per 10ms
      1MS (1000) : Every task should run at least once per 1ms
      100US (100) : Every task should run at least once per 100uS
      30FPS (33333) : Thirty Frames per Second

4.6.56.  tick_color - Color values for ticks within range parameters

      GREEN (0) : Green Area
      YELLOW (1) : Yellow Area
      RED (2) : Red Area
      WHITE (3) : White Area
      CLEAR (4) : Empty / no color
      BLUE (5) : Blue line -- does not change color above

4.6.57.  com_state - State of communication radio

      IDLE (R) : Ready to Receive (Idle)
      RX (r) : Active receiving
      TX (T) : Active transmitting
      STUCK (S) : Stuck Mic
      FAULT (F) : Fault

4.6.58.  com_target - COM Radio Target Destination

      INAIR (0) : Radio used primarily for in-air communication
      GROUND (1) : Radio used primiarly for on/to-ground communication
      BOTH (2) : Radio used equally for in-air and on-ground
      communication

4.6.59.  ics_mode - State of intercom system

      PILOT (P) : Pilot Isolate
      CREW (C) : Crew Isolate
      ALL (A) : All
      FEATUREMASK (0xff00) : Mask for intercom features
      POSITIONAL ((1U << 8)) : Positional dynamic audio

4.6.60.  xpdr_mode - Transponder mode and flags

      UNKNOWN (0) : Unknown
      MODEMASK (0x7f) : Mask for mode
      STANDBY (O) : Standby
      GND (G) : On Ground



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      AIR (A) : Air/Altitude Reporting
      FLAG_IDENT ((1U << 7)) : IDENT Active

4.6.61.  traffic_type - Traffic threat categorization

      NONTHREAT (0) : Non Threatening
      PROXIMITY (1) : Proximity
      ADVISORY (2) : Advisory
      RESOLUTION (3) : Resolution

4.6.62.  nav_flag - Navigational flag states

      BACKCOURSE ((1U << 0)) : NAV receiver is flying a localizer back
      course
      LOCDETECT ((1U << 1)) : The NAV receiver is detecting a localizer
      FROM ((1U << 2)) : The FROM flag is detected from a VOR
      TO ((1U << 3)) : The TO flag is detected from a VOR
      GSI_SFLAG ((1U << 4)) : The glideslope superflag is present
      GSI_VALID ((1U << 5)) : The glideslope signal is being received
      and is valid
      NAV_SFLAG ((1U << 6)) : The NAV super flag is present
      NAV_VALID ((1U << 7)) : The localizer or VOR signal is being
      received and is valid
      FAULT ((1U << 8)) : Fault detected

4.6.63.  weightbal_station - Weight and balance station types

      HULL (1) : This station corresponds to the basic empty aircraft
      FUEL (2) : This station is a fuel tank.  Its weight will be in
      XFS_PARAM_FUELWT
      PASSENGER (3) : This station contains a passenger
      BAGGAGE (4) : This station contains baggage or cargo

4.6.64.  weightbal_category - Aircraft operational categories

      NORMAL (1) : Normal Category
      UTILITY (2) : Utility Category
      ACROBATIC (3) : Acrobatic Category
      COMMUTER (4) : Commuter Category

4.6.65.  weightbal_status - Weight and balance status

      OK (0) : Weight and balance is OK
      FWD ((1U << 0)) : Balance is forward of minimum CG for this weight
      AFT ((1U << 1)) : Balance is aft of maximum CG for this weight
      OVWTSTATN ((1U << 2)) : One or more stations are overweight
      OVERMGTOW ((1U << 3)) : Weight exceeds maximum gross takeoff
      weight



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      OVERMLW ((1U << 4)) : Weight exceeds max landing weight
      OVERZFW ((1U << 5)) : Weight exceeds max zero fuel weight

4.6.66.  flight_state - Status of aircraft within flight profile

      UNKNOWN (0) : The state of the aircraft is not known
      OFF (1) : The aircraft is completely powered down
      HIBERNATE (2) : Minimal aircraft systems online not visible to the
      pilot
      PREFLIGHT (3) : Minimal aircraft systems for pilot interaction
      online
      ENGINE_START (4) : Engine(s) are preparing to start or are
      starting
      PRETAXI (5) : Engine(s) are started, awaiting pre-taxi items
      TAXI (6) : Aircraft is ready or in process of taxiing
      RUNUP (7) : Aircraft is ready for, or in process of performing
      runup
      READY (8) : Aircraft is ready for and positioned just short of
      takeoff
      TAKEOFF (9) : Aircraft is in process of performing takeoff
      AFTER_TAKEOFF (10) : Aircraft is airborne immediately but not yet
      configured for normal climb
      DEPARTURE (11) : Aircraft is on a standard instrument departure
      CLIMB (12) : Aircraft is climbing but not on an instrument
      departure
      CRUISE (13) : Aircraft is at final cruise
      DESCENT (14) : Aircraft is descending not on a standard arrival
      ARRIVAL (15) : Aircraft is on a standard arrival
      APPROACH (16) : Aircraft is on an instrument approach procedure
      VISUAL (17) : Aircraft is flying a visual traffic pattern
      MISSED (18) : Aircraft is executing a missed approach
      SHUTDOWN (19) : Aircraft engines are shutting down or have shut
      down
      SECURE (20) : Aircraft systems are shutting down or reconfiguring
      for preflight

4.6.67.  nav_gps - Global positioning system status

      UNKNOWN (0) : GPS Navigation is in unknown state
      ENROUTE (1) : GPS Navigation is in Enroute state
      TERMINAL (2) : GPS Navigation is Terminal state
      LNAV (3) : GPS Navigation is in Lateral Navigation State
      LNAVVNAV (4) : GPS Navigation is Lateral and Vertical NAV state
      LP (5) : GPS Navigation is in Localizer Performance state
      LPV (6) : GPS Navigation is in Localizer Performance/Vertical
      state





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4.6.68.  ecb_state - Electronic circuit breaker status

      UNKNOWN (0) : Circuit is in an unknown condition
      OFF (1) : Circuit is turned off
      ON (2) : Circuit is turned on
      UNDERCUR (3) : Circuit is on, <100ma current drawn
      RESET (4) : Request Reset
      FORWARD (5) : ECB is active logical FWD direction
      REVERSE (6) : ECB is active logical REV direction
      TARGET (7) : ECB is set by target, not ON/OFF
      BRAKELOW (8) : ECB is set by target, not ON/OFF
      SHORTED (128) : Short Circuit
      OVERCUR (129) : Overcurrent (but not short circuit)
      OVERVOL (130) : Overvoltage situation
      DISABLED (131) : Disabled by state-fault
      RUNAWAY (132) : Disabled due to runaway (trim/flaps)
      COLLARED (133) : Should not reset in flight
      JAMMED (134) : Mechanical Jam detected
      PULLED (135) : Pulled
      BACKFLOW (136) : Disabled due to reverse current flow

4.6.69.  ecb_flag - Electronic circuit breaker parameter flags

      INPUTVOLTS ((1U << 0)) : Input Volts field is valid

4.6.70.  scb_state - Software circuit breaker states

      UNKNOWN (0) : State of software is unknown
      STARTING (1) : Application is in startup phase
      RUNNING (2) : Application is running
      STOPPING (3) : Stopping has been requested
      RESTART (4) : Restart Application (PULL + RESET + START)
      RESET (5) : Allow application to be started
      HUNG (6) : Application is running but is no longer responsive
      DEGRADED (127) : Application is running in a degraded mode
      STOPPED (128) : Application is stopped
      STARTFAIL (129) : Application failed startup
      RUNAWAY (130) : Application has a runaway loop
      OVERCPU (131) : Application is using excessive CPU while in
      RUNNING state
      OVERMEM (132) : Application terminated due to memory overrun
      EXCEPTION (133) : Application terminated due to runtime exception
      ENDED (134) : Application ended without error or request
      ENDERROR (135) : Application ended with error condition
      PULLED (136) : Application should not be allowed to run until
      reset
      COLLARED (137) : Should not reset in flight




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4.6.71.  afcs_fd_mode - Vertical, lateral and yaw modes of flight
         director

      VERT_MASK (0xff) : Vertical modes mask
      LAT_MASK (0xff00) : Lateral modes mask
      YAW_MASK (0xff000000) : Yaw modes mask
      PITCH ((1U << 0)) : Activate pitch mode
      VS ((1U << 1)) : Activate vertical speed mode
      FLC ((1U << 2)) : Activate indicated airspeed mode / flight level
      change
      PRF ((1U << 3)) : Activate angle of attack / performance mode
      ALT ((1U << 4)) : Arm Altitude mode
      VNAV ((1U << 5)) : Arm vertical nav mode
      GP ((1U << 6)) : Arm approach mode vertical portion
      FLARE ((1U << 7)) : Arm flare mode
      ROLL ((1U << 8)) : Activate wing leveler mode
      HDG ((1U << 9)) : Activate heading mode
      NAV ((1U << 10)) : Arm navigation mode
      APPR ((1U << 11)) : Arm approach mode
      YD ((1U << 24)) : Fixed Yaw Damper
      SLIP ((1U << 25)) : Activate slip mode (adjustable YD)
      SLIPAPPR ((1U << 26)) : Activate approach slip mode (adjustable
      YD)

4.6.72.  afcs_ap_mode - Vertical, lateral and yaw modes of autopilot and
         throttle

      VERT_MASK (0xff) : Vertical modes mask
      LAT_MASK (0xff00) : Lateral modes mask
      THROT_MASK (0xff0000) : Throttle modes mask
      YAW_MASK (0xff000000) : Yaw modes mask
      PITCH ((1U << 0)) : Pitch mode
      EPPITCH ((1U << 1)) : Pitch mode only for envelope protection
      ROLL ((1U << 8)) : Roll mode
      EPROLL ((1U << 9)) : Roll mode only for envelope protection
      SPD ((1U << 16)) : Activate autothrottle speed tracking
      EPSPD ((1U << 17)) : Autothrottle only for envelope protection
      (SPD mode)
      AOA ((1U << 18)) : Activate autothrottle AoA tracking
      EPAOA ((1U << 19)) : Autothrottle only for envelope protection
      (AOA mode)
      TOGA ((1U << 20)) : Activate takeoff / go-around throttle
      EPTOGA ((1U << 21)) : Autothrottle only for envelope protection
      (TOGA mode)
      YAW ((1U << 24)) : Yaw mode
      EPYAW ((1U << 25)) : Yaw envelope protection





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4.6.73.  afcs_servo - Servo engagement flags

      ENGAGE ((1U << 31)) : If present in engagement request, along with
      'ENGAGED' value, set engagment status
      ENGAGED (1) : For requests, retain current engagement state, for
      status, present if currently engaged
      DISENGAGED (0) : If engaged, disengage and for status, currently
      disengaged

4.6.74.  fms_flag - Flight management system waypoint and leg flags

      NONE (0) : No flags or leg type known
      LEGTYPE_VA (1) : Heading to Altitude
      LEGTYPE_VD (2) : Heading to DME Distance
      LEGTYPE_VI (3) : Heading to Next Leg Intercept
      LEGTYPE_VM (4) : Heading to Manual Termination
      LEGTYPE_VR (5) : Heading to Radial Termination
      LEGTYPE_CA (6) : Course to an Altitude
      LEGTYPE_CD (7) : Course to a DME Distance
      LEGTYPE_CI (8) : Course to Next Leg Intercept
      LEGTYPE_CR (9) : Course to Radial Termination
      LEGTYPE_CF (10) : Course to a Fix
      LEGTYPE_TF (11) : Tracking Between Two Fixes
      LEGTYPE_DF (12) : Direct to a Fix
      LEGTYPE_FA (13) : Course from a Fix to an Altitude
      LEGTYPE_FC (14) : Course from a Fix to an Along Track Distance
      LEGTYPE_FD (15) : Course from a Fix to a DME Distance
      LEGTYPE_FM (16) : Course from a Fix to a Manual Termination
      LEGTYPE_AF (17) : Constant DMA Arc to a Fix
      LEGTYPE_HF (18) : Hold to a Fix
      LEGTYPE_HA (19) : Hold to an Altitude
      LEGTYPE_HM (20) : Hold to a Manual Termination
      LEGTYPE_IF (21) : Initial Fix
      LEGTYPE_PI (22) : Procedure Turn to Intercept
      LEGTYPE_RF (23) : Radius to a Fix
      LEGTYPE_MASK (0xff) : Mask with which to retrieve leg type
      FLYOVER ((1U << 8)) : If not present, fly by
      DISC ((1U << 9)) : If present, Discontinuity before current
      waypoint
      ACTIVE ((1U << 10)) : If present, this is the active waypoint
      OBS ((1U << 11)) : If present, waypoint allows OBS to be set
      FAF ((1U << 12)) : If present, waypoint is final approach fix or
      after
      SUSPEND ((1U << 13)) : FMS sequencing is suspended at this
      waypoint
      LAST ((1U << 14)) : This waypoint is the last one in the flight
      plan




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4.6.75.  fms_waypoint - Flight management system waypoint types

      UNKNOWN (0) : Unknown or unspecified
      GS ((1U << 7)) : Glideslope component
      DME ((1U << 6)) : DME Component
      TACAN ((1U << 5)) : TACAN Component
      VOR (1) : VOR Component
      LOC (2) : Localizer component
      NDB (3) : NDB component
      LDA (4) : LDA Component
      SDF (5) : SDF Component
      FIX (6) : Generic RNAV Fix
      ILS (7) : Complete ILS system
      AIRPORT (8) : An Airport
      DIRECTFROM (9) : Starting point of a direct to
      WEATHER (10) : Weather reporting station only

4.6.76.  fms_waypoint_subunit - Special subunits used within the FMS

      FIRST (1) : Starting waypoint of flight plan
      FIRSTAP (65530) : First airport within flight plan
      PREV (65531) : Starting waypoint of the active leg (if leg is not
      a direct to)
      NEXT (65532) : Ending waypoint of the active leg
      LASTAP (65533) : Final airport of flight plan if more than one
      airport in plan
      LAST (65534) : Final waypoint of flight plan

4.6.77.  fms_airport - Flight management system airport types

      UNKNOWN (0) : Unknown type of airport
      AIRPORT (1) : An actual airport
      BALLOON (2) : A Balloonport
      SEAPLANE (3) : A Seaplane Base
      GLIDER (4) : A Glider Port
      HELIPORT (5) : A Heliport
      ULTRALIGHT (6) : Ultralight Field
      FLAG_CUSTOMS ((1U << 8)) : Customs Available
      FLAG_TOWER ((1U << 9)) : Tower Available
      FLAG_PUBLIC ((1U << 10)) : Public Use
      FLAG_CLOSEDIND ((1U << 11)) : Closed Indefinitely
      FLAG_CLOSEDPERM ((1U << 12)) : Closed Permenantly
      FLAG_JETA ((1U << 13)) : JET-A Available
      FLAG_100LL ((1U << 14)) : 100LL Available
      FLAG_MOGAS ((1U << 15)) : Oxygen Available
      FLAG_BEACON ((1U << 16)) : Beacon Present
      FLAG_AFMAJOR ((1U << 17)) : Major Airframe
      FLAG_AFMINOR ((1U << 18)) : Minor Airframe



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      FLAG_PPMAJOR ((1U << 19)) : Powerplant Major
      FLAG_PPMINOR ((1U << 20)) : Powerplant Minor
      FLAG_OXYGEN ((1U << 21)) : Oxygen Available
      FLAG_MILITARY ((1U << 22)) : Military

4.6.78.  fms_rwy - Flight management system runway parameters and flags

      SURF_UNKNOWN (0) : Unknown Surface
      SURF_ASPHALT ((1U << 0)) : Asphalt
      SURF_CONC ((1U << 1)) : Concrete
      SURF_SNOW ((1U << 2)) : Snow
      SURF_ICE ((1U << 3)) : Ice
      SURF_MATS ((1U << 4)) : Mats
      SURF_TREATED ((1U << 5)) : Oiled
      SURF_GRAVEL ((1U << 6)) : Gravel
      SURF_TURF ((1U << 7)) : Grass / Sod
      SURF_DIRT ((1U << 8)) : Natural Soil
      SURF_WATER ((1U << 9)) : Water Runway
      SURF_OTHER ((1U << 10)) : Wood
      SURF_MATERIAL_MASK (0x7ff) : Mask for surface material
      SURF_EXCL ((1U << 11)) : Excellent Condition
      SURF_GOOD ((1U << 12)) : Good Condition
      SURF_FAIR ((1U << 13)) : Fair Condition
      SURF_POOR ((1U << 14)) : Poor Condition
      SURF_FAILED ((1U << 15)) : Failed Condition
      SURF_COND_MASK (0xf800) : Mask for surface material
      LIGHTS_HIGH ((1U << 16)) : Edge Lights High
      LIGHTS_MED ((1U << 17)) : Medium Edge Lights
      LIGHTS_LOW ((1U << 18)) : Low Edge Lights
      LIGHTS_NSTD ((1U << 19)) : Non-Standard
      LIGHTS_NONE ((1U << 20)) : No Edge Lights
      LIGHTS_OTHER ((1U << 21)) : Other edge lights
      RIGHT_HAND ((1U << 22)) : Right Hand Traffic

4.6.79.  fms_container - Flight management system container types

      UNKNOWN (0) : Unspecified or unknown container
      NONE (1) : No container
      VICTOR (2) : VOR Airway
      JET (3) : Jet Airway
      AMBER (4) : Amber Airway
      BLUE (5) : Blue Airway
      GREEN (6) : Green Airway
      RED (7) : Red Airway
      Q (8) : RNAV Q Routes
      T (9) : RNAV T Routes
      STAR (10) : Standard Arrival Procedure
      DP (11) : Standard Departure Procedure



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      APP (12) : Instrument Approach
      RWY (13) : Airport Runway Surface Selection

4.6.80.  fms_airspace - Flight management system airspace types and
         flags

      CLASS_A (A) : Class A Airspace
      CLASS_B (B) : Class B Airspace
      CLASS_C (C) : Class C Airspace
      CLASS_D (D) : Class D Airspace
      AGLFLAG ((1U << 20)) : If present in positive numbers, Airspace is
      relative to ground level
      AAFLAG ((1U << 21)) : If present, in positive number, airspace is
      capped by the airspace above

4.6.81.  osk_key - On screen keyboard keys

      0 (48) : Character 0
      1 (49) : Character 1
      2 (50) : Character 2
      3 (51) : Character 3
      4 (52) : Character 4
      5 (53) : Character 5
      6 (54) : Character 6
      7 (55) : Character 7
      8 (56) : Character 8
      9 (57) : Character 9
      A (65) : Character A
      B (66) : Character B
      C (67) : Character C
      D (68) : Character D
      E (69) : Character E
      F (70) : Character F
      G (71) : Character G
      H (72) : Character H
      I (73) : Character I
      J (74) : Character J
      K (75) : Character K
      L (76) : Character L
      M (77) : Character M
      N (78) : Character N
      O (79) : Character O
      P (80) : Character P
      Q (81) : Character Q
      R (82) : Character R
      S (83) : Character S
      T (84) : Character T
      U (85) : Character U



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      V (86) : Character V
      W (87) : Character W
      X (88) : Character X
      Y (89) : Character Y
      Z (90) : Character Z
      PREV (60) : Previous position or <
      NEXT (62) : Next position or >
      DEG (127) : Degrees
      DIRECTTO (128) : Direct To
      ENT (129) : Enter

4.6.82.  chart_type - Instrument procedure and airport chart/diagram
         types

      APPROACH (1) : Instrument Approach
      DEPARTURE (2) : Instrument Departure
      ARRIVAL (3) : Instrument Arrival
      DIAGRAM (4) : Airport Diagram
      HOTSPOT (5) : Hot Spot
      LAHSO (6) : Land and Hold Short
      ALTMIN (7) : Alternate Minimums
      OBSDEP (8) : Obstacle Departure Procedure
      DEPAAU (9) : Departure / Attention All Users
      SUPPLEMENT (255) : Supplemental Data

4.6.83.  db_param - Database parameter identifiers and formats

      FORMAT_MASK ((0xffU << 24)) : Mask for Format portion
      FORMAT_INT ((0 << 24)) : 32-bit 2's complement signed integer
      FORMAT_FLOAT ((1U << 24)) : IEEE 754 floating point number
      FORMAT_STRING ((2U << 24)) : Optionally NULL terminated string
      AIRPORT (0) : Airport Name
      SERVICE (1) : Service name (e.g. ATIS, AWOS, TOWER, APPROACH,
      DEPARTURE, CENTER, CLEARANCE, GROUND)
      FREQKHZ_DEPRECATED (2) : Frequency in Khz
      COMMENT (3) : Comment associated with Frequency
      PHONE (4) : Phone number
      SECONDARY (5) : If a value is secondary, it's priority (lower is
      higher priority)
      FIXNAME (6) : Name of Fix
      LATITUDE (7) : Latitude
      FLAGS (8) : Generic flags
      CONTAINER (9) : Name of airway, arrival, star or other container
      CTYPE (10) : Type of container
      WTYPE (11) : Type of FIX/Waypoint
      INBOUND (12) : Inbound magnetic course
      OUTBOUND (13) : Outbound magnetic course in
      MAGADJ (14) : Magnetic Adjustment



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      ALTITUDE (15) : Altitude (MSL)
      LONGNAME (16) : Full name of fix or airport or airspace
      LONGITUDE (17) : Longitude
      APTTYPE (18) : Type of landing facility
      OPCOUNT (19) : Operations Count per year
      CITY (20) : Associated City
      STATE (21) : Associated State
      COUNTRY (22) : Associated Country
      RWYNAME (23) : Runway Name
      RWYSIZE (24) : Length in bottom 20 bits, Width in top 12 bits
      RWYLAT (25) : Lat of runway End
      RWYLON (26) : Lon of runway End
      RWYTHRS (27) : Displaced Threshold
      RWYSURF (28) : Runway Surface
      RWYALIGN (29) : Runway true alignment (in degrees)
      RWYELV (30) : Runway threshold elevation
      FLOOR (31) : Signed integer altitude floor in feet
      CEIL (32) : Altitude ceiling in feet
      AIRNAME (33) : Name / Class of airspace
      ALTAGL (34) : Altitude (AGL)
      OBSLIGHT (35) : Obstacle Lighting (from DOF)
      MOCA (36) : Minimum Crossing Altitude
      MCA (37) : Minimum Crossing Altitude
      MCAR (38) : Minimum Crossing Altitude (Reverse)
      MEA (39) : Minimum Enroute Altitude
      MEAR (40) : Minimum Enroute Altitude (Reverse)
      GMEA (41) : (GNSS) Minimum Enroute Altitude
      GMEAR (42) : (GNSS) Minimum Enroute Altitude (Reverse)
      MAXAA (43) : Maximum Authorized Altitude
      CLONGNAME (44) : Long Name of container
      PROCNAME (45) : Procedure or Chart Name
      CHARTTYPE (46) : Type of Chart
      IMAGENAME (47) : Image Name for Procedure
      TOP (48) : Top location in 1/10000 of a percent of full scale
      RIGHT (49) : Right location in 1/10000 of a percent of full scale
      BOTTOM (50) : Bottom location in 1/10000 of a percent of full
      scale
      LEFT (51) : Left location in 1/10000 of a percent of full scale
      XLOC (52) : X location in 1/10000 of a percent of full scale
      YLOC (53) : Y location in 1/10000 of a percent of full scale
      ORIENTATION (54) : Orientation in 1/10000 of a degree
      PROXIMITY (55) : Proximity of closest neighbor
      FREQMHZ (56) : Frequency

4.6.84.  db_hashfunc - Database hash functions

      IDENT (1) : Alphanumeric Identifier
      INT (2) : Integer Number



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4.6.85.  devtype - XFS device types

      MCP (1) : Master Control Program
      ADC (2) : Air Data Computer Only
      AHRS (3) : Attitude Heading Reference System Only
      ADAHRS (4) : ADC and AHRS Combined
      SIM (5) : Simulated Data
      DSU (6) : Data Storage Unit -- Records Data
      FD (7) : Flight Director
      AP (8) : Automatic Pilot
      FMS (9) : Flight Management System
      PDU (10) : Power Distribution Unit
      TRIGGER (11) : Event Trigger Unit
      QAR (12) : Quick Access Recorder
      UI (13) : User Interface Device (but not flight display)
      COM (14) : Communication Radio
      NAV (15) : Navigation Radio
      AUDIOPANEL (16) : Audio Panel
      XPDR (17) : Transponder
      DAU (18) : Data Acquisition Unit (e.g. Engine)
      XFD (19) : Generic Flight Display
      SYNSENSOR (20) : Synthetic Sensor
      EFIS (21) : Integrated Standby EFIS
      OVERLAY (22) : Display overlay (e.g. System or Moving Map)
      SERVO (23) : Generic Servo Unit
      AIRFRAME (24) : Airframe specific description
      GPIO (25) : Generic GPIO Interface
      BRIDGE (26) : Protocol Bridge
      PROPGOV (27) : Propeller Governor control
      DATALINK (28) : Generic Data Link
      HAT (29) : Device for measuring height above terrain

4.6.86.  suip_cmd - Serial User Interface Protocol commands

      DATATX (0x0001) : Send data to specific address.
      LONGPRESSTIME (0x0002) : How many milliseconds for a Long press
      (16-bit unsigned value in data)
      GENINC (0x0003) : Generic Encoder Increase
      GENDEC (0x0004) : Generic Encoder Decrease
      GENPUSH (0x0005) : Generic Encoder or Button Push
      GENLONGPUSH (0x0006) : Generic Encoder or Button Long Push
      GENRELEASE (0x0007) : Generic Encoder or Button Release
      IDENTREQ (0x000c) : Identify Device connected
      IDENTREP (0x000d) : Return identity to CPU (data is null
      terminated string)
      BRIGHTNESS (0x000e) : Addr is which device to change brightness (0
      for all), data is 16 bits 0 (dark) to 65535 (bright)




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      ISALIVE (0x000f) : Periodic message sent to indicate link is
      alive.  Address is 0
      CONFIG (0x0010) : Device specific configuration.  Address is
      device specific
      QUERY (0x0011) : Device specific query.  Address is device
      specific
      REPLY (0x0012) : Device specific reply.  Address is device
      specific
      DEBUG (0x0000) : Fake message which has debug info in it

4.6.87.  touch_event - Touch event activities

      UNASSIGNED (0) : Touch event has not been assigned yet
      ORPHAN (1) : Touch did not begin within target
      LOST (2) : Touch did not remain within target
      ABANDON (3) : Touch released outside target
      PRESS (4) : Pressing on a touch surface
      DRAG (5) : Drag to a new location
      PINCH (6) : Two related touches dragged to new positions
      RELEASE (255) : Releasing from a touch surface

4.6.88.  gpio_output - General purpose I/O output states

      NULL (0x00) : NO, GPIO port not available / not installed
      FLOAT (0x01) : FL, No pull up or pull down
      PULLDOWN (0x02) : PD, pulldown ~ 2.2k
      PULLUP (0x03) : PU, pullup ~ 2.2k
      LOW (0x04) : OL, Drive output value low
      HIGH (0x05) : OH, Drive output value high
      PULL_PWM (0x06) : PP, Drive output as PWM/DAC through pullup/down
      PWM (0x07) : PW, Drive output as PWM/DAC
      FAULT ((1U << 3)) : OF, Fault condition (Rx only), Clear fault (Tx
      only)

4.6.89.  gpio_input - General purpose I/O input states

      NULL (0x00) : NI, GPIO port not available / not installed
      LOW (0x01) : IL, Read value is low
      HIGH (0x02) : IH, Read value is high
      FAULT (0x03) : IF, Fault condition (Rx only), Clear fault (Tx
      only)

4.6.90.  gpio_feature - General purpose I/O feature flags

      ANALOG ((1U << 0)) : Is analog requested

4.6.91.  gdl90_event - GDL-90 event Codes




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      INVALID (0) : Invalid sequence
      BADCHECKSUM (1) : Checksum invalid
      OTHER (2) : Other event - with raw data
      HEARTBEAT (3) : Heartbeat event
      OWNSHIP (4) : Ownship event (see traffic portion)
      TRAFFIC (5) : Traffic event
      GEOALT (6) : Geo Altitude for Ownship
      UPLINK (7) : Generic Uplink Event

4.6.92.  gdl90_emergency - GDL-90 Emergency and priority codes

      NONE (0) : No emergency
      GENERAL (1) : General unspecified emergency
      MEDICAL (2) : Medical emergency
      MINIMUM_FUEL (3) : Minimum fuel
      NORDO (4) : No Communications
      HIJACK (5) : Unlawful interference
      DOWNED (6) : Downed aircraft

4.6.93.  gdl90_emitter - GDL-90 Traffic Emitter Category

      NO_INFO (0) : No information available
      LIGHT (1) : Under 15,500 lbs
      SMALL (2) : 15,500 lbs to 75,000 lbs
      LARGE (3) : 75,000 to 300,000 lbs
      HIGH_VORTEX (4) : B757 etc
      HEAVY (5) : Over 300,000 lbs
      MANUEVERABLE (6) : Over 5G acceleration
      ROTORCRAFT (7) : Rotary Wing Aircraft
      GLIDER (9) : Glider or Sailplane
      AIRSHIP (10) : Lighter than air
      SKYDIVER (11) : Sky diver or parachutist
      ULTRALIGHT (12) : Ultralight / Hang Glider
      UAV (14) : Unmanned aircraft
      SPACE (15) : Space / Transatmospheric vehicle
      EMERGENCY (17) : Surface / emergency vehicle
      SERVICE (18) : Surface / service vehicle
      POINTOBSTACLE (19) : Point Obstacle (including tethered balloon)
      CLUSTEROBSTACLE (20) : Cluster of obstacles
      LINEOBSTACLE (21) : Line of obstacles

4.6.94.  gdl90_traffic_alert - GDL-90 Traffic Alert Status

      NONE (0) : No alert active for target
      ALERT (1) : Alert active for target

4.6.95.  gdl90_traffic_addr - GDL-90 Traffic Address Type




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      ADSB_ICAO (0) : ICAO Assigned
      ADSB_SELF (1) : Self Assigned
      TISB_ICAO (2) : ICAO Assigned
      TISB_TRACK_FILE (3) : Track File ID
      SURFACE_VEHICLE (4) : Surface Vehicle
      GROUND_STATION_BEACON (5) : Ground Station Beacon

4.6.96.  gdl90_heartbeat_status1 - GDL-90 Heartbeat First Status Byte
         Bitmask

      GPS_POS_VALID ((1U << 7)) : Position is available for ADS-B Tx
      GDL90_MAINT_REQD ((1U << 6)) : GDL 90 Maintenance is Required
      IDENT_TALKBACK ((1U << 5)) : IDENT Talkback
      ADDR_TALKBACK ((1U << 4)) : Address Type Talkback
      GPS_BATT_LOW ((1U << 3)) : GPS Battery Low
      RATCS ((1U << 2)) : ATC Services Talkback
      UAT_INITIALIZED ((1U << 0)) : GDL90 is initialized

4.6.97.  gdl90_heartbeat_status2 - GDL-90 Heartbeat Second Status Byte
         Bitmask

      CSA_REQUESTED ((1U << 6)) : CSA has been requested
      CSA_NOT_AVAILABLE ((1U << 5)) : CSA not available at this time
      UTC_TIMING_VALID ((1U << 0)) : UTC timing is valid

4.6.98.  gdl90_track_status - GDL-90 status of traffic track value

      INVALID (0) : trackheading field is meaningless
      TRUETRACK (1) : trackheading field represents true track
      MAGHDG (2) : trackheading field represents magnetic heading
      TRUEHDG (3) : trackheading field represents true heading

4.6.99.  fisb_event - Datalink FIS-B (SRT-047 or DO-358) events

      CNEXRAD (1) : CONUS NEXRAD
      RNEXRAD (2) : Regional NEXRAD
      GENTEXT (3) : Generic Text
      SUA (4) : Special Use Airspace Status
      ICINGLOW (5) : Low Level Forecast Icing Product
      ICINGHIGH (6) : High Level Forecast Icing Product
      TURBLOW (7) : Low Level Forecast Turbulence
      TURBHIGH (8) : High Level Forecast Turbulence
      LIGHTNING (9) : Lightning
      CLOUDTOPS (10) : Cloud Tops
      GAIRMET (11) : Graphical AIRMET Outline
      SIGMETOUTLINE (12) : SIGMET Outline
      SIGMETTEXT (13) : SIGMET Text
      AIRMETOUTLINE (14) : AIRMET Outline



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      AIRMETTEXT (15) : AIRMET Text
      NOTAMOUTLINE (16) : NOTAM/TFR Outline
      NOTAMTEXT (17) : NOTAM/TFR Text
      CWAOUTLINE (18) : Center Weather Advisory Outline
      CWATEXT (19) : Center Weather Advisory Text

4.6.100.  fisb_geometry - SRT-047/DO-358 datalink FIS-B geometries

      3DPG_MSL (3) : 3D Polygon MSL Altitude
      3DPG_AGL (4) : 3D Polygon AGL Altitude
      CP_MSL (7) : Circular Prism MSL Altitude
      CP_AGL (8) : Circular Prism AGL Altitude
      3DPT_AGL (9) : 3D Point AGL Altitude
      3DPT_MSL (10) : 3D Point MSL Altitude
      3DPL_MSL (11) : 3D Polyline MSL Altitude
      3DPL_AGL (12) : 3D Polyline AGL Altitude

4.6.101.  gblock_res - SRT-047/DO-358 Global Block Resolution

      HIGH (1) : High Resolution (1x)
      MEDIUM (5) : Medium Resolution (5x)
      LOW (9) : Low Resolution (9x)

4.6.102.  hid_event - Human Interface Device Events

      NONE (0) : No event has occured.  Should still be called
      frequently if no other events happen
      ICC (1) : Inner Counter Clockwise
      IC (2) : Inner Clockwise
      OCC (3) : Outer Counter Clockwise
      OC (4) : Outer Clockwise
      KPUSH (5) : Push on knob
      BPUSH (6) : Button Push
      KREL (7) : Knob Release
      BREL (8) : Button Release

4.6.103.  ethertun_dlc - Special data length field parameters for
          ethernet tunnel of CAN

      TIMESTAMP ((1U << 7)) : Timestamp field present

4.6.104.  analog_avg_feature - Features for analog averaging

      NONE (0) : Normal Average
      HEADING (1) : Average range 0-360 with wrapping
      PITCH (2) : Average range -90.0 to 90.0 with wrapping
      ROLL (3) : Average range -180.0 to 180.0 with wrapping




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4.6.105.  milstd1553 - Maximum sequence number for MIL-STD-1553 over
          ethernet

      SEQNO_MASK (0x3fff) : Max Sequence number

4.6.106.  milstd1553_frame_flag - Frame flags for MIL-STD-1553 frames

      STATUS1 ((1U << 0)) : Status1 is Valid
      STATUS2 ((1U << 1)) : Status2 is Valid
      ADDR1 ((1U << 2)) : Rtaddr1 and Subaddr1 are Valid
      ADDR2 ((1U << 3)) : Rtaddr2 and Subaddr2 are Valid
      MODECODE ((1U << 4)) : Modecode is Valid
      MAILBOX ((1U << 15)) : Treat this message as a mailbox prototype

4.6.107.  milstd1553_rtaddr - Remote terminal addresses for MIL-STD-1553

      TRANSMIT ((1U << 7)) : This command has transmit bit set (if not
      present, receive bit)
      MASK (0x1f) : Mask for station vs flags
      ALL (0x1f) : All Stations
      UNSPEC (0x20) : RT is unspecified

4.6.108.  milstd1553_subaddr - Subaddresses for remote terminals for
          MIL-STD-1553

      MODECODE0 (0x0) : Mode Code (0)
      MODECODE31 (0x1f) : Mode Code (31)
      UNSPEC (0x20) : Subaddress is unspecified

4.6.109.  milstd1553_modecode - MIL-STD-1553 special mode codes

      DYNBUSCTRL (0x00) : Dynamic Bus Control
      SYNC (0x01) : Synchronize
      TXSTATW (0x02) : Transmit Status Word
      SELFTEST (0x03) : Initiate Self Test
      TXSD (0x04) : Transmitter Shutdown
      OVTXSD (0x05) : Override Transmitter Shutdown
      INHIBIT (0x06) : Inhibit Terminal Flag
      OVINHIBIT (0x07) : Override Inhibit Terminal Flag
      RESET (0x08) : Reset Remote Terminal
      TXVECTW (0x10) : Transmit Vector Word
      SYNCWDATA (0x11) : Synchronize (with Data) (R)
      TXLASTCW (0x12) : Transmit Last Command Word
      TXBITW (0x13) : Transmit BIT Word
      SELTXSD (0x14) : Selected Transmitter Shutdown (R)
      OVSELTXSD (0x15) : Override Selected Transmitter Shutdown (R)
      UNSPEC (0x20) : Mode code is unspecified




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4.6.110.  milstd1553_status - MIL-STD-1553 status bits

      RTMASK (0x1f) : Mask for station vs flags
      MSGERROR ((1U << 15)) : Message Error
      INSTRMNT ((1U << 14)) : Instrumentation
      SVCREQ ((1U << 13)) : Service Request
      BRDCSTRX ((1U << 9)) : Broadcast Received
      BUSY ((1U << 8)) : Busy
      SUBSYSFLAG ((1U << 7)) : Subsystem Flag
      DYNBUSCTRLAC ((1U << 6)) : Dynamic Bus Control Accept
      TERMFLAG ((1U << 5)) : Terminal Flag

4.6.111.  arinc429_speed - ARINC-429 baud rates

      FAST (100000) : ARINC-429 High Speed
      SLOW (12500) : ARINC-429 Low Speed

4.6.112.  arinc429_bcd - ARINC-429 Binary Coded Decimal

      PLUS ((0 << 29)) : SSM Positive Number
      NCD ((1 << 29)) : SSM No Computed Data
      FT ((2 << 29)) : SSM Functional Test
      MINUS ((3 << 29)) : SSM Negative Number

4.6.113.  arinc429_dd - ARINC-429 Discrete Data

      NORM ((0 << 29)) : SSM Normal Operation
      NCD ((1 << 29)) : SSM No Computed Data
      FT ((2 << 29)) : SSM Functional Test
      FAIL ((3 << 29)) : SSM Failure Warning

4.6.114.  arinc429_bnr - ARINC-429 Binary Number

      FAIL ((0 << 29)) : SSM Failure Warning
      NCD ((1 << 29)) : SSM No Computed Data
      FT ((2 << 29)) : SSM Functional Test
      NORM ((3 << 29)) : SSM Normal Operation
      PLUS ((0 << 28)) : SM Positive Number
      MINUS ((1 << 28)) : SM Negative Number

4.6.115.  canaero_datatype - CANAERO datatypes and encodings

      NODATA (0) : No data type
      ERROR (1) : Emergency event data type
      FLOAT (2) : Single precision IEE-754
      LONG (3) : 2's complement integer
      ULONG (4) : Unsigned integer
      BLONG (5) : Collection of 32 individual bits



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      SHORT (6) : 2's complement short integer
      USHORT (7) : Unsigned 16-bit integer
      BSHORT (8) : Collection of 16 individual bits
      CHAR (9) : 2's complement char integer
      UCHAR (10) : unsigned 8-bit integer
      BCHAR (11) : Collection of 8 individual bits
      SHORT2 (12) : 2 x 2's complement short integer
      USHORT2 (13) : 2 x unsigned 16-bit integer
      BSHORT2 (14) : 2 x collection of 16 individual bits
      CHAR4 (15) : 4 x 2's complement char integer
      UCHAR4 (16) : 4 x unsigned 8-bit
      BCHAR4 (17) : 4 x collection of 8 individual bits
      CHAR2 (18) : 2 x 2's complement char integer
      UCHAR2 (19) : 2 x unsigned 8-bit integer
      BCHAR2 (20) : 2 x collection of 8 individual bits
      MEMID (21) : Memory ID for upload/download
      CHKSUM (22) : Checksum for upload/download
      ACHAR (23) : ASCII Character
      ACHAR2 (24) : 2x ASCII Character
      ACHAR4 (25) : 4x ASCII Character
      VARIABLE3 (100) : 17 to 24-bits of signed 2's complement integer
      UVARIABLE3 (101) : 17 to 24-bits of unsigned integer

4.6.116.  parambuf_interpflag - Parameter buffer interpretation flags

      NONE (0) : No interpretation flags
      STRICT ((1U << 0)) : Confidence must exactly match minconfidence
      CROSSFILL ((1U << 1)) : Crossfill equivalent values from
      appropriate better scoring peers
      PROMISC ((1U << 2)) : Interpret from all sources and do not attach
      to a single one
      OPTIONAL ((1U << 3)) : The presence of this parameter is not
      required for normal operation

4.6.117.  parambuf_flag - Parameter buffer state flags

      NONE (0) : No flags
      VALID ((1U << 0)) : Set to true by receive logic when paramter
      buffer is valid
      UPDATED ((1U << 1)) : Set by receive logic when paramter buffer
      has been updated
      LINKED ((1U << 2)) : When this flag is set, this parameter buffer
      has been linked in a parameter set

4.6.118.  serial_dbits - Serial Data Bits

      DB8 (0) : Eight Data Bits
      DB7 (1) : Seven Data Bits



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4.6.119.  serial_parity - Serial Data Parity

      NONE (0) : No Parity Bit
      ODD (1) : Odd Parity Bit
      EVEN (2) : Even Parity Bit

4.6.120.  serial_sbits - Serial Stop Bits

      SB1 (0) : One Stop Bit
      SB2 (1) : Two Stop Bits

4.6.121.  link_state - Serial Interface Link State

      DISCONNECTED (-1) : Interface is currently not connected
      STATELESS (0) : Interface does not track state
      CONNECTED (1) : Interface is currently connected

4.6.122.  object_factory_flag - Object Factory Flags

      VIRTUAL ((1 << 0)) : Virtual objects cannot be directly
      instantiated -- only their non-virtual children
      OSSPECIFIC ((1 << 1)) : Objects defined within the operating
      system abstraction may be absent or have different parameters on
      other O/S selections
      OPTIONAL ((1 << 2)) : Optional object factories can be ignored if
      their parent object types have no registered factory
      REGISTERED ((1 << 3)) : If present, this object factory has been
      registered within the list of valid object types
      FOUNDLINEAGE ((1 << 4)) : If present, this object factory has
      found its full lineage up to the root OBJECT parent

4.6.123.  scb_flag - Software Circuit Breaker Flags

      NONE (0) : Application running within normal paramters
      HIGHMEM ((1 << 0)) : Application has used unexpectedly high
      portion of memory
      HIGHCPU ((1 << 1)) : Application has used unexpectedly high
      portion of CPU
      HIGHBW ((1 << 2)) : Application has used unexpectedly high portion
      of network bandwidth

4.6.124.  priv_proto - Privacy Protocols

      NONE (0) : No privacy protocol
      DES (1) : Data Encryption Standard
      AES (2) : 128-Bit Advanced Encryption Standard
      AES192 (3) : 192-Bit Advanced Encryption Standard
      AES256 (4) : 256-Bit Advanced Encryption Standard



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4.6.125.  crc16_poly - CRC-16 Polynomials

      POSTXOR ((1 << 16)) : XOR Block data after table lookup rather
      than before (nonstandard for GDL-90)
      CCITT (0x1021) : GDL-90 (when in conjunction with POSTXOR flag),
      CRC-16 CCITT
      ANSI (0x8005) : ANSI X3.28, USB, MODBUS and others

4.6.126.  a661_widgetid - ARINC-661 Widget IDs

      NOWIDGET (0) : No selected widget

4.6.127.  a661_layerid - ARINC-661 Layer IDs

4.6.128.  a661_color - ARINC-661 Color Indices

4.6.129.  a661 - ARINC-661 Special Values

      FALSE (0x00) : False
      TRUE (0x01) : True
      UNSELECTED (0x00) : Not selected
      SELECTED (0x01) : Selected
      TRUE_WITH_VALIDATION (0x02) : True and Validated
      BEGIN_BLOCK (0xB0) : Start keyword opening a runtime block of
      information
      END_BLOCK (0xD0) : Keyword ending a block of runtime information
      CMD_SET_PARAMETER (0xCA02) : Set a parameter on a widget
      CMD_UA_REQUEST (0xCA03) : Set parameter
      NOTIFY_WIDGET_EVENT (0xCC01) : Received Widget Event
      NOTIFY_LAYER_EVENT (0xCC02) : Received Layer Event
      NOTIFY_EXCEPTION (0xCC03) : Received Exception Event
      REQ_LAYER_ACTIVE (0xDA01) : Request a layer become active
      REQ_LAYER_INACTIVE (0xDA02) : Request a layer become inactive
      REQ_LAYER_VISIBLE (0xDA04) : Request a layer become the visible
      layer
      REQ_CURSOR_ON_WIDGET (0xDA05) : Request cursor be snapped to a
      widget
      REQ_FOCUS_ON_WIDGET (0xDA03) : Request focus be snapped to a
      widget
      ERR_BAD_COMMAND (0xF001) : Erroneous command
      ERR_PROCESS_OVERLOAD (0xF006) : Inability to complete processing
      ERR_RENDERING_OVERLOAD (0xF007) : Inability to complete rendering
      ERR_SET_ABORTED (0xF003) : Erroneous set command
      ERR_UA_REQUEST_ABORTED (0xF004) : Erroneous UA Request
      NOTE_CYCLIC_ACTIVATION (0xDC82) : Periodic Indication that Layer
      is Active
      NOTE_LAYER_IS_ACTIVE (0xDC02) : Layer Activated by CDS and
      Reinitialize Data



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      NOTE_LAYER_IS_INACTIVE (0xDC03) : Layer Deactivated by CDS
      NOTE_REINIT_LAYER_DATA (0xDC01) : CDS Requests Data Layer
      Initialization
      NOTE_CONNECTOR_DATA (0xDC86) : Parametric Data Update
      EVT_ANIMATION_STATUS_CHANGE (0xE509) : Animation Status has
      completed (1 byte)
      EVT_CLICKED (0xE1D1) : Item has been clicked
      EVT_CURSOR_ENTER (0xE300) : Cursor enters active area
      EVT_CURSOR_EVENT (0xE305) : Event from cursor event extension
      EVT_CURSOR_EXIT (0xE320) : Cursor exits active area
      EVT_CURSOR_INSIDE (0xE310) : Cursor inside active area
      EVT_CURSOR_POS_CHANGE (0xE010) : Cursor position has changed
      EVT_GESTURE_DIR_FLICK (0xE508) : Direction of one or more points
      quickly moved in a direction
      EVT_DOUBLE_CLICKED (0xE1D2) : Double click event
      EVT_GESTURE_DRAG (0xE506) : One or more points move in a direction
      EVT_EDITBOX_OPENED (0xE110) : Edit box has been opened for entry
      EVT_FIRST_VIS_ENTRY_CHANGE (0xE020) : First visible entry in a
      list has changed
      EVT_GESTURE_FLICK (0xE507) : Velocity of one or more points
      quickly moved in a direction
      EVT_FRAME_POS_CHANGE (0xE030) : Change in X/Y Position of Frame
      EVT_GESTURE_DOUBLE_TAP (0xE502) : Two taps in quick succession and
      close proximity
      EVT_GESTURE_TAP (0xE501) : Single tap and release
      EVT_INCREMENT (0xE006) : Device Increment
      EVT_ITEM_SYNCHRONIZATION (0xE150) : Map Item Synchronization
      EVT_ITEM_IN_BOUNDS (0xE141) : List of in-bounds map items
      EVT_ITEM_OUT_OF_BOUNDS (0xE140) : List of out-of-bounds map items
      EVT_KEY (0xE005) : Virtual Keyboard KeyPress
      EVT_MULT_SELECTION (0xE058) : Multiple entry list (extension)
      selection entry
      EVT_OFFSCREEN (0xE0E0) : Map element has gone off screen
      EVT_ONSCREEN (0xE0E1) : Map element has come on screen
      EVT_GESTURE_PINCH (0xE504) : Pinch Gesture
      EVT_POPUP_CLOSED (0xE040) : Popup menu or button closed
      EVT_POPUP_PANEL_CLOSED (0xE120) : Popup panel closed
      EVT_GESTURE_PRESS_AND_HOLD (0xE503) : Area pressed and held
      EVT_PRESSED (0xE1D3) : Area pressed
      EVT_RELEASED (0xE1D4) : Area released
      EVT_RIGHT_CLICKED (0xE1D5) : Area right clicked
      EVT_GESTURE_ROTATE (0xE505) : Rotation gesture
      EVT_SEL_ENTRY_CHANGE (0xE050) : Selection entry has changed
      EVT_SELECTION (0xE060) : Item has been selected
      EVT_SELECTION_MAP (0xE068) : Map location has been selected
      EVT_STATE_CHANGE (0xE070) : Item state has changed
      EVT_STRING_CHANGE (0xE080) : String value has been changed but not
      confirmed or aborted



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      EVT_STRING_CHANGE_ABORTED (0xE090) : String value change has been
      canceled
      EVT_STRING_CONFIRMED (0xE0A0) : String value change has been
      confirmed
      EVT_TABBED_PANEL_CHANGE (0xE0B0) : Selected tabbed panel has
      changed
      EVT_TOUCH (0xE500) : A touch has taken place
      EVT_VALUE_CHANGE (0xE0C0) : Slider value has changed
      EVT_VISIBLE_CHILD (0xE0D0) : Visible child within paging container
      has changed
      EVT_VISIBLE_CHILD_INDEX (0xE0D1) : Index of visible child within
      paging container has changed
      EVT_WATCHDOG_EXPIRED (0xE200) : Watchdog has expired
      EVT_WATCHDOG_NORMAL (0xE210) : Watchdog status is normal
      EVT_ANY (0xFFFF) : XFS-Specific Any Event
      STRING (0xB490) : String value parameter
      STRING_ARRAY (0xB4A0) : Collection of NUL-separated and terminated
      string values parameter
      SELECTED_ENTRY (0xB430) : Selected entry within a list
      NUMBER_OF_ENTRIES (0xB2A0) : Number of entries within a list
      VISIBLE_CHILD (0xB540) : Visible child page/mutex container
      ENTRY_VALID (0xB570) : Entry has been validated when non-zero
      COLOR_INDEX (0xB160) : Index of Color to be used for border
      FILL_INDEX (0xB1E0) : Index of Color to be used for fill
      ENABLE (0xB180) : Enable for interaction
      VALUE (0xB520) : Floating Point Numeric Value
      START_ANGLE (0xB480) : 32-bit signed numeric value for starting
      angle
      END_ANGLE (0xB1B0) : 32-bit signed numeric value for ending angle
      VISIBLE (0xB530) : Is widget visible
      INNER_STATE_CHECK (0xB244) : Is toggle checked
      INNER_STATE_TOGGLE (0xB258) : Is toggle selected
      EN_DEFSTR (0xBA11) : Collins Extension for Edit Number to show
      default string
      SIZE_X (0xB450) : Width of widget
      SIZE_Y (0xB460) : Height of widget

4.6.130.  com_secmode - Communication Security Mode

      TD (1) : TD
      PT (2) : Plain Text
      CT (7) : Cypher Text
      INVALID (8) : Invalid Reserved
      RV (14) : RV

4.6.131.  com_band - Communication Band

      UNKNOWN (0) : Unknown communication band



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      VHFFM (1) : Very High Frequency with Frequency Modulation
      VHFAM (2) : Very High Frequency Amplitude Modulation
      UHFFM (3) : Ultra High Frequency
      UHFAM (4) : Ultra High Frequency
      P25A (5) : Project 25 Analog
      P25D (6) : Project 25 Digital
      P25T (7) : Project 25 Trunk Mode
      TSM (8) : Trellisware Scalable Mobile Ad-hoc NETworking
      SATCOM (9) : Satellite Communication
      SINCGARS (10) : SINCGARS Frequency Hop Frequencies
      HFAM (11) : High Frequency Ampltitude Modulation

4.6.132.  com_bandmask - Supported Communication Band Mask

      VHFFM ((1 << 0)) : Very High Frequency with Frequency Modulation
      VHFAM ((1 << 1)) : Very High Frequency with Amplitude Modulation
      UHFFM ((1 << 2)) : Ultra High Frequency with Frequency Modulation
      UHFAM ((1 << 3)) : Ultra High Frequency with Amplitude Modulation
      P25A ((1 << 4)) : Project 25 Analog
      P25D ((1 << 5)) : Project 25 Digital
      P25T ((1 << 6)) : Project 25 Trunk Mode
      TSM ((1 << 7)) : Trellisware Scalable Mobile Ad-hoc NETworking
      SATCOM ((1 << 8)) : Satellite Communication
      SINCGARS ((1 << 9)) : SINCGARS Frequency Hop Frequencies
      HFAM ((1 << 10)) : High Frequency

4.6.133.  com_sqlmode - Communication Squelch Mode

      UNKNOWN (0) : Unknown Squelch Mode
      NONE (1) : Squelch Off
      SNR (2) : Signal to Noise Ratio
      TONE (3) : FM Military Tone Squelch System
      CTCSS (4) : Continuous Tone Coded Squelch System
      DCS (5) : Digital Code Squelch
      NAC (6) : Network Access Code P25 Trunk Mode

4.6.134.  com_scgopmode - SINCGARS Operational Mode

      UNKNOWN (0) : Unknown SINCGARS Mode
      SINGLECHANNEL (1) : Single channel mode is active
      FREQHOP (2) : Frequency hoping is active
      FREQHOPMASTER (3) : Frequency hop and is master

4.6.135.  percent - Percentage Value

4.6.136.  graphic_prim - Graphic Primative

      POINTS (0) : Vertices in space



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      LINES (1) : Lines between pairs of vertices
      LINE_LOOP (2) : Connect all vertices into a closed loop
      LINE_STRIP (3) : Connect all vertices into a single line
      TRIANGLES (4) : Triangles between sets of three vertices
      TRIANGLE_STRIP (5) : Connect all vertices into a single strip of
      triangles
      TRIANGLE_FAN (6) : Connect all vertices into a fan of triangles

4.7.  Parameter Types

   This section declares the initial set of XSEDE parameters.  Each
   parameter is defined by a name and a short description.  This is
   followed by the numeric parameter ID.  Next, the meanings of the unit
   and subunit fields are provided, if applicable. and finally the
   parameter data format and a reference to the appropriate table
   defining the parameter attribute type.

4.7.1.  GOAROUND - Go around requested

      Parameter ID: %x00.00.00
      Unit Usage: None
      SubUnit Usage: None
      Format: BOOL (See Table 24.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.2.  P-ALT - Pressure Altitude

      Parameter ID: %x00.00.01
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: FT multiplied by 10.

4.7.3.  T-ALT - True Altitude

      Parameter ID: %x00.00.02
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: FT multiplied by 10.

4.7.4.  IAS - Indicated Airspeed

      Parameter ID: %x00.00.03
      Unit Usage: Source ID
      SubUnit Usage: None



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      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.5.  CAS - Calibrated Airspeed

      Parameter ID: %x00.00.04
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.6.  CASMSG - Crew Alerting System Message

      Parameter ID: %x00.00.05
      Unit Usage: CAS System ID
      SubUnit Usage: None
      Format: CASMSG (See Table 32.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.7.  THROTPOS - Throttle position

      Parameter ID: %x00.00.06
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.8.  INAIR - Are we in the air (vs. on the ground)

      Parameter ID: %x00.00.07
      Unit Usage: None
      SubUnit Usage: None
      Format: BOOL (See Table 24.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.9.  BARO - Current barometric setting

      Parameter ID: %x00.00.08
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: INHG multiplied by 1000.





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4.7.10.  CLTPOS - Collective Position

      Parameter ID: %x00.00.09
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.11.  CLTPOSREQ - A/P Requested Collective Position

      Parameter ID: %x00.00.0a
      Unit Usage: None
      SubUnit Usage: None
      Format: SERVO (See Table 47.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.12.  MAGHDG - Magnetic Heading

      Parameter ID: %x00.00.0b
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: HDG (See Section 4.5.2.6.)
      Units: DEG multiplied by 100.

4.7.13.  MAGCRS - Magnetic Course (via RNAV)

      Parameter ID: %x00.00.0c
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: HDG (See Section 4.5.2.6.)
      Units: DEG multiplied by 100.

4.7.14.  TRUECRS - True Course (via RNAV)

      Parameter ID: %x00.00.0d
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: HDG (See Section 4.5.2.6.)
      Units: DEG multiplied by 100.





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4.7.15.  MAGDTK - Desired Course (via RNAV)

      Parameter ID: %x00.00.0e
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: HDG (See Section 4.5.2.6.)
      Units: DEG multiplied by 100.

4.7.16.  TRUEDTK - Desired course (via RNAV)

      Parameter ID: %x00.00.0f
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: HDG (See Section 4.5.2.6.)
      Units: DEG multiplied by 100.

4.7.17.  LAT - Current position latitude

      Parameter ID: %x00.00.10
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: DEG multiplied by 10000000.

4.7.18.  LON - Current position longitude

      Parameter ID: %x00.00.11
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: DEG multiplied by 10000000.

4.7.19.  RNAVALT - Altitude measured by RNAV

      Parameter ID: %x00.00.12
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: FT multiplied by 10.





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4.7.20.  ROLL - Current degrees of roll, -18000 being being upside down
         towards left, 18000 being upside down to the right

      Parameter ID: %x00.00.13
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: ROLL (See Section 4.5.2.2.)
      Units: DEG multiplied by 100.

4.7.21.  PITCH - Current degrees of pitch, 9000 being straight up, -9000
         being straight down

      Parameter ID: %x00.00.14
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: PITCH (See Section 4.5.2.3.)
      Units: DEG.

4.7.22.  YAW - Yaw/Inclination as measured in G force

      Parameter ID: %x00.00.15
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: G multiplied by 10000.

4.7.23.  FUELWTTOT - Computed remaining fuel

      Parameter ID: %x00.00.16
      Unit Usage: Fuel System ID/0=Sum of all
      SubUnit Usage: 0 = current total, 1 = total at end of flight
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: LB multiplied by 100.

4.7.24.  RNAVHFOM - Horizontal Figure of Merit

      Parameter ID: %x00.00.17
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: M multiplied by 100.



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4.7.25.  RNAVVFOM - Vertical Figure of Merit

      Parameter ID: %x00.00.18
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: M multiplied by 100.

4.7.26.  RNAVHPL - Horizontal Protection Level

      Parameter ID: %x00.00.19
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: M multiplied by 100.

4.7.27.  RNAVVPL - Vertical Protection Level

      Parameter ID: %x00.00.1a
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: M multiplied by 100.

4.7.28.  IASRT - Indicated Airspeed Rate of Change

      Parameter ID: %x00.00.1b
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KTPS multiplied by 100.

4.7.29.  KBDSEL - Activate the named on-screen keyboard or none if empty

      Parameter ID: %x00.00.1c
      Unit Usage: Display
      SubUnit Usage: None
      Format: STRING (See Table 31.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.30.  KEYPRESS - Send the FMS encoded key press to the given display

      Parameter ID: %x00.00.1d
      Unit Usage: Display



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      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using osk_key dictionary (See Table 53.)

   Table 53, below, shows the values defined in the osk-key Dictionary.
   These options represent the On screen keyboard keys.

               +==========+=======+========================+
               | Name     | Value | Definition             |
               +==========+=======+========================+
               | 0        | %d48  | Character 0            |
               +----------+-------+------------------------+
               | 1        | %d49  | Character 1            |
               +----------+-------+------------------------+
               | 2        | %d50  | Character 2            |
               +----------+-------+------------------------+
               | 3        | %d51  | Character 3            |
               +----------+-------+------------------------+
               | 4        | %d52  | Character 4            |
               +----------+-------+------------------------+
               | 5        | %d53  | Character 5            |
               +----------+-------+------------------------+
               | 6        | %d54  | Character 6            |
               +----------+-------+------------------------+
               | 7        | %d55  | Character 7            |
               +----------+-------+------------------------+
               | 8        | %d56  | Character 8            |
               +----------+-------+------------------------+
               | 9        | %d57  | Character 9            |
               +----------+-------+------------------------+
               | A        | %d65  | Character A            |
               +----------+-------+------------------------+
               | B        | %d66  | Character B            |
               +----------+-------+------------------------+
               | C        | %d67  | Character C            |
               +----------+-------+------------------------+
               | D        | %d68  | Character D            |
               +----------+-------+------------------------+
               | E        | %d69  | Character E            |
               +----------+-------+------------------------+
               | F        | %d70  | Character F            |
               +----------+-------+------------------------+
               | G        | %d71  | Character G            |
               +----------+-------+------------------------+
               | H        | %d72  | Character H            |
               +----------+-------+------------------------+
               | I        | %d73  | Character I            |



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               +----------+-------+------------------------+
               | J        | %d74  | Character J            |
               +----------+-------+------------------------+
               | K        | %d75  | Character K            |
               +----------+-------+------------------------+
               | L        | %d76  | Character L            |
               +----------+-------+------------------------+
               | M        | %d77  | Character M            |
               +----------+-------+------------------------+
               | N        | %d78  | Character N            |
               +----------+-------+------------------------+
               | O        | %d79  | Character O            |
               +----------+-------+------------------------+
               | P        | %d80  | Character P            |
               +----------+-------+------------------------+
               | Q        | %d81  | Character Q            |
               +----------+-------+------------------------+
               | R        | %d82  | Character R            |
               +----------+-------+------------------------+
               | S        | %d83  | Character S            |
               +----------+-------+------------------------+
               | T        | %d84  | Character T            |
               +----------+-------+------------------------+
               | U        | %d85  | Character U            |
               +----------+-------+------------------------+
               | V        | %d86  | Character V            |
               +----------+-------+------------------------+
               | W        | %d87  | Character W            |
               +----------+-------+------------------------+
               | X        | %d88  | Character X            |
               +----------+-------+------------------------+
               | Y        | %d89  | Character Y            |
               +----------+-------+------------------------+
               | Z        | %d90  | Character Z            |
               +----------+-------+------------------------+
               | PREV     | %d60  | Previous position or < |
               +----------+-------+------------------------+
               | NEXT     | %d62  | Next position or >     |
               +----------+-------+------------------------+
               | DEG      | %d127 | Degrees                |
               +----------+-------+------------------------+
               | DIRECTTO | %d128 | Direct To              |
               +----------+-------+------------------------+
               | ENT      | %d129 | Enter                  |
               +----------+-------+------------------------+

                        Table 53: osk-key Dictionary




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4.7.31.  SURFPOS - Position of arbitrary control surface

      Parameter ID: %x00.00.1e
      Unit Usage: Surface Type
      SubUnit Usage: Surface Type Subassembly
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.32.  SURFREQ - Requested control surface position

      Parameter ID: %x00.00.1f
      Unit Usage: Surface Type
      SubUnit Usage: Surface Type Subassembly
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.33.  SURFTORQUE - Aerodynamic torque applied to a control surface
         relative to movement

      Parameter ID: %x00.00.20
      Unit Usage: Surface Type
      SubUnit Usage: Surface Type Subassembly
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: LBFT multiplied by 100.

4.7.34.  SURFFORCE - Aerodynamic force applied to a control surface
         relative to movement

      Parameter ID: %x00.00.21
      Unit Usage: Surface Type
      SubUnit Usage: Surface Type Subassembly
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: LB multiplied by 100.

4.7.35.  WINDSPD - Wind Speed

      Parameter ID: %x00.00.22
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KT multiplied by 100.





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4.7.36.  WINDBRG - True Bearing from which wind blows

      Parameter ID: %x00.00.23
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: HDG (See Section 4.5.2.6.)
      Units: DEG multiplied by 100.

4.7.37.  COMFREQ - Communication Frequency - If SYS/USERSEL, sets
         COMFREQTX and COMFREQRX.  RAW should match COMFREQTX.

      Parameter ID: %x00.00.24
      Unit Usage: Radio ID
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: COMFREQ (See Section 4.5.2.11.)
      Units: MHZ multiplied by 100000.

4.7.38.  COMFREQR - Range of acceptable communication frequencies

      Parameter ID: %x00.00.24
      Unit Usage: Radio ID
      SubUnit Usage: 0=Current Band/1+=By COM Band
      Format: RANGE (See Table 39.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.39.  NAVFREQ - Navigation Frequency

      Parameter ID: %x00.00.25
      Unit Usage: Radio ID
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: NAVFREQ (See Section 4.5.2.12.)
      Units: MHZ multiplied by 100000.

4.7.40.  COMVOL - Communication Volume (0-100)

      Parameter ID: %x00.00.26
      Unit Usage: Radio ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: PERCENT (See Section 4.5.2.4.)
      Units: PCENT.



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4.7.41.  NAVVOL - Communication Volume (0-100)

      Parameter ID: %x00.00.27
      Unit Usage: Radio ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: PERCENT (See Section 4.5.2.4.)
      Units: PCENT.

4.7.42.  COMSQL - Communication Squelch (0-100)

      Parameter ID: %x00.00.28
      Unit Usage: Radio ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: PERCENT (See Section 4.5.2.4.)
      Units: PCENT.

4.7.43.  MUX - Selected multiplexer input or output

      Parameter ID: %x00.29
      Unit Usage: MUX ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.44.  ICSVOL - Intercom Volume (0-100)

      Parameter ID: %x00.00.2a
      Unit Usage: Audio Panel Unit
      SubUnit Usage: 0=System, 1=Pilot, 2=Copilot, rest are pax
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: PERCENT (See Section 4.5.2.4.)
      Units: PCENT.

4.7.45.  COMSTATE - COM radio state

      Parameter ID: %x00.00.2b
      Unit Usage: Radio ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using com_state dictionary (See Table 54.)





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   Table 54, below, shows the values defined in the com-state
   Dictionary.  These options represent the State of communication
   radio.

                +=======+=======+=========================+
                | Name  | Value | Definition              |
                +=======+=======+=========================+
                | IDLE  | R     | Ready to Receive (Idle) |
                +-------+-------+-------------------------+
                | RX    | r     | Active receiving        |
                +-------+-------+-------------------------+
                | TX    | T     | Active transmitting     |
                +-------+-------+-------------------------+
                | STUCK | S     | Stuck Mic               |
                +-------+-------+-------------------------+
                | FAULT | F     | Fault                   |
                +-------+-------+-------------------------+

                       Table 54: com-state Dictionary

4.7.46.  ICSRXCOMS - Which COM Radios to Monitor (mask)

      Parameter ID: %x00.00.2c
      Unit Usage: Audio Panel Unit
      SubUnit Usage: 0=System, 1=Pilot, 2=Copilot, rest are pax
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.47.  ICSRXNAVS - Which NAV Radios to Monitor (mask)

      Parameter ID: %x00.00.2d
      Unit Usage: Audio Panel Unit
      SubUnit Usage: 0=System, 1=Pilot, 2=Copilot, rest are pax
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.48.  ICSMODE - Intercom Mode

      Parameter ID: %x00.00.2e
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using ics_mode dictionary (See Table 55.)

   Table 55, below, shows the values defined in the ics-mode Dictionary.
   These options represent the State of intercom system.




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          +=============+=========+============================+
          | Name        | Value   | Definition                 |
          +=============+=========+============================+
          | PILOT       | P       | Pilot Isolate              |
          +-------------+---------+----------------------------+
          | CREW        | C       | Crew Isolate               |
          +-------------+---------+----------------------------+
          | ALL         | A       | All                        |
          +-------------+---------+----------------------------+
          | FEATUREMASK | %xff.00 | Mask for intercom features |
          +-------------+---------+----------------------------+
          | POSITIONAL  | %x01.00 | Positional dynamic audio   |
          +-------------+---------+----------------------------+

                      Table 55: ics-mode Dictionary

4.7.49.  ICSTXCOMS - Which COM Radios to Transmit (mask)

      Parameter ID: %x00.00.2f
      Unit Usage: Audio Panel Unit
      SubUnit Usage: 0=System, 1=Pilot, 2=Copilot, rest are pax
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.50.  DATETIME - Date and Time

      Parameter ID: %x00.00.30
      Unit Usage: 0=Current Zulu Time
      SubUnit Usage: None
      Format: DATETIME (See Table 50.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.51.  GLOAD - Current Normal to Aircraft Loading

      Parameter ID: %x00.00.31
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: G multiplied by 1000.

4.7.52.  RATEOFTURN - Turn Coordinator Rate Per Second

      Parameter ID: %x00.00.32
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.



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      Units: DEG multiplied by 1000.

4.7.53.  GROUNDSPEED - Groundspeed

      Parameter ID: %x00.00.33
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.54.  VSPEED - Vertical speed

      Parameter ID: %x00.00.34
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: FPM multiplied by 1.

4.7.55.  XPDRIDENT - XPDR Ident request (USERSELECT only).  Non-standby
         transponders must IDENT regardless of UNIT.  Used only to
         request IDENT, but IDENT state reported in XPDRMODE

      Parameter ID: %x00.00.35
      Unit Usage: Always zero
      SubUnit Usage: None
      Format: BOOL (See Table 24.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.56.  XPDRRPS - XPDR Replies per second (normalized)

      Parameter ID: %x00.00.36
      Unit Usage: XPDR ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.57.  XPDRSQUAWK - XPDR Squawk in octal.  All transponders must
         change SQUAWK regardless of UNIT

      Parameter ID: %x00.00.37
      Unit Usage: XPDR ID (Rx Only) Zero for USERSELECT
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using octal dictionary (See Table 56.)




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   Table 56, below, shows the values defined in the octal Dictionary.
   These options represent the Octal representation.

                 +=======+=======+======================+
                 | Name  | Value | Definition           |
                 +=======+=======+======================+
                 | octal | N/A   | Octal representation |
                 +-------+-------+----------------------+

                        Table 56: octal Dictionary

4.7.58.  XPDRMODE - XPDR Mode.  Note that IDENT flag is ignored in
         USERSELECT condition.

      Parameter ID: %x00.00.38
      Unit Usage: XPDR ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using xpdr_mode dictionary (See Table 57.)

   Table 57, below, shows the values defined in the xpdr-mode
   Dictionary.  These options represent the Transponder mode and flags.

              +============+=======+========================+
              | Name       | Value | Definition             |
              +============+=======+========================+
              | UNKNOWN    | %d0   | Unknown                |
              +------------+-------+------------------------+
              | MODEMASK   | %x7f  | Mask for mode          |
              +------------+-------+------------------------+
              | STANDBY    | O     | Standby                |
              +------------+-------+------------------------+
              | GND        | G     | On Ground              |
              +------------+-------+------------------------+
              | AIR        | A     | Air/Altitude Reporting |
              +------------+-------+------------------------+
              | FLAG-IDENT | %x80  | IDENT Active           |
              +------------+-------+------------------------+

                       Table 57: xpdr-mode Dictionary

4.7.59.  NAVOBS - NAV OBS Value

      Parameter ID: %x00.00.39
      Unit Usage: Radio/FMS ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)



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      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: OBS (See Section 4.5.2.7.)
      Units: DEG multiplied by 1000.

4.7.60.  NAVBRG - Bearing to nav aid

      Parameter ID: %x00.00.3a
      Unit Usage: Radio/FMS ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: HDG (See Section 4.5.2.6.)
      Units: DEG multiplied by 100.

4.7.61.  NAVCDI - Course Deviation (-1000 to 1000)

      Parameter ID: %x00.00.3b
      Unit Usage: Radio/FMS ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: DEVIATION (See Section 4.5.2.8.)

4.7.62.  NAVGSI - Glide Slope (-1000 to 1000)

      Parameter ID: %x00.00.3c
      Unit Usage: Radio/FMS ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: DEVIATION (See Section 4.5.2.8.)

4.7.63.  NAVFLAGS - Navigation Flags (see XFS_NAV_FLAG_*

      Parameter ID: %x00.00.3d
      Unit Usage: Radio/FMS ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using nav_flag dictionary (See Table 58.)

   Table 58, below, shows the values defined in the nav-flag Dictionary.
   These options represent the Navigational flag states.








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         +============+=========+================================+
         | Name       | Value   | Definition                     |
         +============+=========+================================+
         | BACKCOURSE | %x01    | NAV receiver is flying a       |
         |            |         | localizer back course          |
         +------------+---------+--------------------------------+
         | LOCDETECT  | %x02    | The NAV receiver is detecting  |
         |            |         | a localizer                    |
         +------------+---------+--------------------------------+
         | FROM       | %x04    | The FROM flag is detected from |
         |            |         | a VOR                          |
         +------------+---------+--------------------------------+
         | TO         | %x08    | The TO flag is detected from a |
         |            |         | VOR                            |
         +------------+---------+--------------------------------+
         | GSI-SFLAG  | %x10    | The glideslope superflag is    |
         |            |         | present                        |
         +------------+---------+--------------------------------+
         | GSI-VALID  | %x20    | The glideslope signal is being |
         |            |         | received and is valid          |
         +------------+---------+--------------------------------+
         | NAV-SFLAG  | %x40    | The NAV super flag is present  |
         +------------+---------+--------------------------------+
         | NAV-VALID  | %x80    | The localizer or VOR signal is |
         |            |         | being received and is valid    |
         +------------+---------+--------------------------------+
         | FAULT      | %x01.00 | Fault detected                 |
         +------------+---------+--------------------------------+

                       Table 58: nav-flag Dictionary

4.7.64.  FLAPREQ - Requested Flap Position 0 = up, 100000 = fully down,
         -100000 is fully negative

      Parameter ID: %x00.00.3e
      Unit Usage: Actuator/0=Aircraft
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.65.  FLAPPOS - Flap actuator position, 0 = up, 100000 = fully down,
         -100000 is fully negative

      Parameter ID: %x00.00.3f
      Unit Usage: Actuator/0=Aircraft
      SubUnit Usage: None
      Format: SINT (See Table 35.)



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      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.66.  ECBSTAT - ECB Status change or request, see xfs_ecb.h

      Parameter ID: %x00.00.40
      Unit Usage: None
      SubUnit Usage: None
      Format: BUS (See Table 36.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.67.  PTRIMREQ - Requested Pitch Trim Position (negative nose down, 0
         neutral, positive nose up)

      Parameter ID: %x00.00.41
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.68.  PTRIMPOS - Pitch Trim Position (negative nose down, 0 neutral,
         positive nose up)

      Parameter ID: %x00.00.42
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.69.  RTRIMREQ - Requested Roll Trim Position (negative left bank, 0
         neutral, positive right bank)

      Parameter ID: %x00.00.43
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.70.  RTRIMPOS - Roll Trim Position (negative left bank, 0 neutral,
         positive right bank)

      Parameter ID: %x00.00.44
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)



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      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.71.  BUSSTAT - Status of Bus

      Parameter ID: %x00.00.45
      Unit Usage: None
      SubUnit Usage: None
      Format: BUS (See Table 36.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.72.  TEMP - Arbitrary Temperature in a location

      Parameter ID: %x00.00.46
      Unit Usage: Location
      SubUnit Usage: Sensor Number/0=Average
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.73.  TAS - True Airspeed

      Parameter ID: %x00.00.47
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.74.  TAT - Total Air Temperature

      Parameter ID: %x00.00.48
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.75.  OAT - Outside Air Temperature accounting for compressibility

      Parameter ID: %x00.00.49
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.





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4.7.76.  D-ALT - Density Altitude

      Parameter ID: %x00.00.4a
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: FT multiplied by 10.

4.7.77.  OILPRES - Oil Pressure

      Parameter ID: %x00.00.4b
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PSI multiplied by 100.

4.7.78.  OILTEMP - Oil Temp

      Parameter ID: %x00.00.4c
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.79.  XFDFPS - XFD Display Frames Per Second (FPS)

      Parameter ID: %x00.00.4d
      Unit Usage: Display
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.80.  TIREPRES - Tire Pressure

      Parameter ID: %x00.00.4e
      Unit Usage: Bogey
      SubUnit Usage: Tire
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PSI multiplied by 100.

4.7.81.  CHT - Cylinder Head Temperature

      Parameter ID: %x00.00.4f
      Unit Usage: Engine



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      SubUnit Usage: Cylinder/0=Max
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.82.  EGT - Exhaust Gas Temperature

      Parameter ID: %x00.00.50
      Unit Usage: Engine
      SubUnit Usage: Cylinder/0=Max
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.83.  COOLTEMP - Coolant Temperature

      Parameter ID: %x00.00.51
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.84.  FUELWTFLOW - Fuel Flow by Weight

      Parameter ID: %x00.00.52
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: LBPH multiplied by 100.

4.7.85.  FUELPRES - Fuel Pressure

      Parameter ID: %x00.00.53
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PSI multiplied by 100.

4.7.86.  FUELWT - Fuel Weight

      Parameter ID: %x00.00.54
      Unit Usage: Fuel Tank ID/0=Sum of all
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.



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      Units: LB multiplied by 100.

4.7.87.  MANPRES - Manifold pressure

      Parameter ID: %x00.00.55
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: INHG multiplied by 1000.

4.7.88.  ENGRPM - Engine RPM

      Parameter ID: %x00.00.56
      Unit Usage: Engine
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.

4.7.89.  PROPRPM - Propeller RPM

      Parameter ID: %x00.00.57
      Unit Usage: Engine
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.

4.7.90.  MACH - Mach

      Parameter ID: %x00.00.58
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: MACH multiplied by 10000.

4.7.91.  IASBUG - Target indicated airspeed

      Parameter ID: %x00.00.59
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.92.  HDGBUG - Bugged Magnetic Heading

      Parameter ID: %x00.00.5a



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      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: HDG (See Section 4.5.2.6.)
      Units: DEG multiplied by 100.

4.7.93.  ALTBUG - Bugged Altitude

      Parameter ID: %x00.00.5b
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: FT multiplied by 10.

4.7.94.  WAYPOINT - A way point in a flight plan, subunit is position in
         flightplan, beginning with 1 for first waypoint.  Subunit 0 is
         only used to indicate an empty flight plan.

      Parameter ID: %x00.00.5c
      Unit Usage: FMS ID
      SubUnit Usage: None
      Format: WAYPOINT (See Table 27.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.95.  INSERT - Insert A way point in a flight plan, subunit is
         position in flightplan which it should become (SYSSEL/USERSEL
         ONLY)

      Parameter ID: %x00.00.5d
      Unit Usage: FMS ID
      SubUnit Usage: None
      Format: WAYPOINT (See Table 27.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.96.  DELETE - Delete A way point in a flight plan, subunit is
         position in flightplan starting at 1 (SYSSEL/USERSEL ONLY).
         Label must match

      Parameter ID: %x00.00.5e
      Unit Usage: FMS ID
      SubUnit Usage: None
      Format: WAYPOINT (See Table 27.)
      Range: There SHALL NOT be a Range Parameter for this parameter.






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4.7.97.  NOTE - Notation of something important within the quick access
         log or bus

      Parameter ID: %x00.00.5f
      Unit Usage: None
      SubUnit Usage: None
      Format: STRING (See Table 31.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.98.  NAVGPS - GPS Mode

      Parameter ID: %x00.00.60
      Unit Usage: NAV radio unit or FMS Unit Number
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using nav_gps dictionary (See Table 59.)

   Table 59, below, shows the values defined in the nav-gps Dictionary.
   These options represent the Global positioning system status.

   +==========+=======+===============================================+
   | Name     | Value | Definition                                    |
   +==========+=======+===============================================+
   | UNKNOWN  | %d0   | GPS Navigation is in unknown state            |
   +----------+-------+-----------------------------------------------+
   | ENROUTE  | %d1   | GPS Navigation is in Enroute state            |
   +----------+-------+-----------------------------------------------+
   | TERMINAL | %d2   | GPS Navigation is Terminal state              |
   +----------+-------+-----------------------------------------------+
   | LNAV     | %d3   | GPS Navigation is in Lateral Navigation State |
   +----------+-------+-----------------------------------------------+
   | LNAVVNAV | %d4   | GPS Navigation is Lateral and Vertical NAV    |
   |          |       | state                                         |
   +----------+-------+-----------------------------------------------+
   | LP       | %d5   | GPS Navigation is in Localizer Performance    |
   |          |       | state                                         |
   +----------+-------+-----------------------------------------------+
   | LPV      | %d6   | GPS Navigation is in Localizer Performance/   |
   |          |       | Vertical state                                |
   +----------+-------+-----------------------------------------------+

                       Table 59: nav-gps Dictionary

4.7.99.  COMFREQTX - Transmit Communication Frequency shares range with
         COMFREQ

      Parameter ID: %x00.00.61



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      Unit Usage: Radio ID
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: COMFREQ (See Section 4.5.2.11.)
      Units: MHZ multiplied by 100000.

4.7.100.  NAVXTK - Cross track error (negative is left)

      Parameter ID: %x00.00.62
      Unit Usage: FMS Unit Number
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: NM multiplied by 1000.

4.7.101.  COMFREQRX - Receive Communication Frequency shares range with
          COMFREQ

      Parameter ID: %x00.00.63
      Unit Usage: Radio ID
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: COMFREQ (See Section 4.5.2.11.)
      Units: MHZ multiplied by 100000.

4.7.102.  BRIGHTNESS - Universal display brightness (0-1000 for night
          time mode, 1000-2000 for daytime modes

      Parameter ID: %x00.00.64
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: BRIGHTNESS (See Section 4.5.2.10.)

4.7.103.  MANTEMP - Manifold temperature

      Parameter ID: %x00.00.65
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: C multiplied by 100.






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4.7.104.  DIRECT - Go direct to a way point in a flight plan, subunit is
          position in flightplan starting at 1 (SYSSEL/USERSEL ONLY).
          Label must match

      Parameter ID: %x00.00.66
      Unit Usage: None
      SubUnit Usage: None
      Format: WAYPOINT (See Table 27.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.105.  ACTIVATE - Activate leg terminating at way point in a flight
          plan, subunit is position in flightplan (SYSSEL/USERSEL ONLY).
          Label must match

      Parameter ID: %x00.00.67
      Unit Usage: None
      SubUnit Usage: None
      Format: WAYPOINT (See Table 27.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.106.  MMPARAM - Moving Map parameters.  Subunit is one of
          XFS_MM_PARAM_*

      Parameter ID: %x00.00.68
      Unit Usage: MOVMAP ID
      SubUnit Usage: XFS_MM_PARAM_*
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.107.  SERVOREQ - Requested servo position and state

      Parameter ID: %x00.00.69
      Unit Usage: None
      SubUnit Usage: None
      Format: SERVO (See Table 47.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.108.  SERVOPOS - Current servo actuator position

      Parameter ID: %x00.00.6a
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.109.  SONICHAT - Ultrasonic rangefinder height above terrain




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      Parameter ID: %x00.00.6b
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: FT multiplied by 100.

4.7.110.  LIDARHAT - LIDAR rangefinder height above terrain

      Parameter ID: %x00.00.6c
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: FT multiplied by 100.

4.7.111.  RADARHAT - Radar rangefinder height above terrain

      Parameter ID: %x00.00.6d
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: FT multiplied by 100.

4.7.112.  HAT - Computed height above terrain

      Parameter ID: %x00.00.6e
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: FT multiplied by 100.

4.7.113.  COMSTANDBY - Standby COM Frequency (same rules and range as
          COMFREQ)

      Parameter ID: %x00.00.6f
      Unit Usage: Radio ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: COMFREQ (See Section 4.5.2.11.)

4.7.114.  NAVSTANDBY - Standby NAV Frequency (same rules and range as
          NAVFREQ)

      Parameter ID: %x00.00.70



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      Unit Usage: Radio ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: NAVFREQ (See Section 4.5.2.12.)

4.7.115.  STALLSPEED - Estimated real-time Stall speed

      Parameter ID: %x00.00.71
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.116.  YTRIMREQ - Requested Yaw Trim Position (negative left, 0
          neutral, positive right)

      Parameter ID: %x00.00.73
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.117.  YTRIMPOS - Yaw Trim Position (negative left, 0 neutral,
          positive right)

      Parameter ID: %x00.00.74
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.118.  VSPEEDBUG - Vertical speed bug in fpm

      Parameter ID: %x00.00.75
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.119.  MUSICSRC - Music Source (0 = none)

      Parameter ID: %x00.00.76
      Unit Usage: Audio Panel Unit
      SubUnit Usage: 0=System, 1=Pilot, 2=Copilot, rest are pax



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      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.120.  AOA - Angle of attack as an actual angle

      Parameter ID: %x00.00.77
      Unit Usage: Source
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: DEG multiplied by 1000.

4.7.121.  AOAR - Angle of attack range -- should contain green
          (beginning of approach range), white (reference angle), yellow
          (approaching stall) and a red (imminent stall)

      Parameter ID: %x00.00.77
      Unit Usage: None
      SubUnit Usage: None
      Format: RANGE (See Table 39.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.122.  GPIO - GPIO Input/Output

      Parameter ID: %x00.00.78
      Unit Usage: I/O Module
      SubUnit Usage: Module Port (0 or 1-8)
      Format: GPIO (See Table 41.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.123.  ANALOG - Raw Analog value 0-4095

      Parameter ID: %x00.00.79
      Unit Usage: I/O Module
      SubUnit Usage: Module Port (1-8)
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.124.  PWM - PWM value 0-4095 -- subunit is port number, 1-8

      Parameter ID: %x00.00.7a
      Unit Usage: I/O Module
      SubUnit Usage: Module Port (1-8)
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.125.  XPDRACID - ICAO 24-bit Aircraft Identifier




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      Parameter ID: %x00.00.7b
      Unit Usage: XPDR ID (Rx Only) Zero for USERSELECT
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using hex dictionary (See Table 60.)

   Table 60, below, shows the values defined in the hex Dictionary.
   These options represent the Hexadecimal representation.

               +======+=======+============================+
               | Name | Value | Definition                 |
               +======+=======+============================+
               | hex  | N/A   | Hexadecimal representation |
               +------+-------+----------------------------+

                          Table 60: hex Dictionary

4.7.126.  XPDRFLID - Up to 8-character, NULL terminated flight ID

      Parameter ID: %x00.00.7c
      Unit Usage: XPDR ID (Rx Only) Zero for USERSELECT
      SubUnit Usage: None
      Format: STRING (See Table 31.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.127.  THROTREQ - Requested throttle position

      Parameter ID: %x00.00.7d
      Unit Usage: None
      SubUnit Usage: None
      Format: SERVO (See Table 47.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.128.  RPMREQ - Prop governor requested RPM

      Parameter ID: %x00.00.7e
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.129.  TACHTIME - Tachometer time, unit is engine

      Parameter ID: %x00.00.7f
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)



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      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: S.

4.7.130.  TOTTIME - Total aircraft time

      Parameter ID: %x00.00.80
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: S.

4.7.131.  APPSTAT - Application Status / Requests

      Parameter ID: %x00.00.00.81
      Unit Usage: CPU ID
      SubUnit Usage: Process ID
      Format: APP (See Table 42.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.132.  CDINAVSRC - Select index (> 0) of CDI NAV Source or 0 for none

      Parameter ID: %x00.00.82
      Unit Usage: Display
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.133.  BRGNAVSRC - Select index (> 0) CDI BRG Source or 0 for none

      Parameter ID: %x00.00.83
      Unit Usage: Display
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.134.  COMSEL - Select COM Radio for Tuning

      Parameter ID: %x00.00.84
      Unit Usage: Display
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.135.  NAVSEL - Select NAV Radio for Tuning

      Parameter ID: %x00.00.85
      Unit Usage: Display



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      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.136.  MSTRCAUTN - Master Caution Active when true.  Resets by
          SYSSEL/USERSEL with value of FALSE

      Parameter ID: %x00.00.86
      Unit Usage: None
      SubUnit Usage: None
      Format: BOOL (See Table 24.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.137.  MSTRWARN - Master Warning Active when true.  Resets by SYSSEL/
          USERSEL with value of FALSE

      Parameter ID: %x00.00.87
      Unit Usage: None
      SubUnit Usage: None
      Format: BOOL (See Table 24.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.138.  ROLLRT - Rate of change of about A/C longitudinal axis (P)

      Parameter ID: %x00.00.88
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: DEGPS multiplied by 1000.

4.7.139.  PITCHRT - Rate of change about A/C transverse axis (Q)

      Parameter ID: %x00.00.89
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: DEGPS multiplied by 1000.

4.7.140.  YAWRT - Rate of change about A/C vertical axis (R)

      Parameter ID: %x00.00.8a
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: DEGPS multiplied by 1000.



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4.7.141.  STKPITCH - Stick Pitch Position (negative nose down, 0
          neutral, positive nose up)

      Parameter ID: %x00.00.8b
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.142.  STKROLL - Stick Roll Position (negative left bank, 0 neutral,
          positive right bank)

      Parameter ID: %x00.00.8c
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.143.  STKYAW - Pedal Yaw Position (negative left, 0 neutral,
          positive right)

      Parameter ID: %x00.00.8d
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)

4.7.144.  BATTTEMP - Battery Temp

      Parameter ID: %x00.00.8e
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.145.  MOTORTEMP - Motor Temp

      Parameter ID: %x00.00.8f
      Unit Usage: Motor
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.




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4.7.146.  POWERTEMP - Temp of a device supplying/converting power to a
          propulsion system

      Parameter ID: %x00.00.90
      Unit Usage: Propulsion System
      SubUnit Usage: Power converter/0=Max
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.147.  TORQUE - Torque

      Parameter ID: %x00.00.91
      Unit Usage: Motor/Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: LBFT multiplied by 100.

4.7.148.  TAILNUM - Up to 8-character, NULL terminated tail number

      Parameter ID: %x00.00.92
      Unit Usage: None
      SubUnit Usage: None
      Format: STRING (See Table 31.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.149.  ROLLREQ - F/D requested degrees of roll in 100 * degrees with
          0 being right side up, -18000 being being upside down towards
          left, 18000 being upside down to the right

      Parameter ID: %x00.00.93
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: ROLL (See Section 4.5.2.2.)

4.7.150.  PITCHREQ - F/D requested degrees of pitch in 100 * degrees
          with 0 being straight ahead, 9000 being straight up, -9000
          being straight down

      Parameter ID: %x00.00.94
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: PITCH (See Section 4.5.2.3.)



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4.7.151.  YAWREQ - F/D requested G force of inclination with 0 being no
          yaw

      Parameter ID: %x00.00.95
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: G multiplied by 10000.

4.7.152.  STKPITCHREQ - A/P Requested Stick Pitch Position (negative
          nose down, 0 neutral, positive nose up)

      Parameter ID: %x00.00.96
      Unit Usage: None
      SubUnit Usage: None
      Format: SERVO (See Table 47.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.153.  STKROLLREQ - A/P Requested Stick Roll Position (negative left
          bank, 0 neutral, positive right bank)

      Parameter ID: %x00.00.97
      Unit Usage: None
      SubUnit Usage: None
      Format: SERVO (See Table 47.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.154.  STKYAWREQ - A/P Requested Pedal Yaw Position (negative left, 0
          neutral, positive right)

      Parameter ID: %x00.00.98
      Unit Usage: None
      SubUnit Usage: None
      Format: SERVO (See Table 47.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.155.  FDMODEACT - Active Flight Director Modes

      Parameter ID: %x00.00.99
      Unit Usage: FD Number (0 for setting values)
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using afcs_fd_mode dictionary (See Table 61.)






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   Table 61, below, shows the values defined in the afcs-fd-mode
   Dictionary.  These options represent the Vertical, lateral and yaw
   modes of flight director.
















































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       +===========+===============+==============================+
       | Name      | Value         | Definition                   |
       +===========+===============+==============================+
       | VERT-MASK | %xff          | Vertical modes mask          |
       +-----------+---------------+------------------------------+
       | LAT-MASK  | %xff.00       | Lateral modes mask           |
       +-----------+---------------+------------------------------+
       | YAW-MASK  | %xff.00.00.00 | Yaw modes mask               |
       +-----------+---------------+------------------------------+
       | PITCH     | %x01          | Activate pitch mode          |
       +-----------+---------------+------------------------------+
       | VS        | %x02          | Activate vertical speed mode |
       +-----------+---------------+------------------------------+
       | FLC       | %x04          | Activate indicated airspeed  |
       |           |               | mode / flight level change   |
       +-----------+---------------+------------------------------+
       | PRF       | %x08          | Activate angle of attack /   |
       |           |               | performance mode             |
       +-----------+---------------+------------------------------+
       | ALT       | %x10          | Arm Altitude mode            |
       +-----------+---------------+------------------------------+
       | VNAV      | %x20          | Arm vertical nav mode        |
       +-----------+---------------+------------------------------+
       | GP        | %x40          | Arm approach mode vertical   |
       |           |               | portion                      |
       +-----------+---------------+------------------------------+
       | FLARE     | %x80          | Arm flare mode               |
       +-----------+---------------+------------------------------+
       | ROLL      | %x01.00       | Activate wing leveler mode   |
       +-----------+---------------+------------------------------+
       | HDG       | %x02.00       | Activate heading mode        |
       +-----------+---------------+------------------------------+
       | NAV       | %x04.00       | Arm navigation mode          |
       +-----------+---------------+------------------------------+
       | APPR      | %x08.00       | Arm approach mode            |
       +-----------+---------------+------------------------------+
       | YD        | %x01.00.00.00 | Fixed Yaw Damper             |
       +-----------+---------------+------------------------------+
       | SLIP      | %x02.00.00.00 | Activate slip mode           |
       |           |               | (adjustable YD)              |
       +-----------+---------------+------------------------------+
       | SLIPAPPR  | %x04.00.00.00 | Activate approach slip mode  |
       |           |               | (adjustable YD)              |
       +-----------+---------------+------------------------------+

                    Table 61: afcs-fd-mode Dictionary





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4.7.156.  FDMODEARM - Armed Flight Director Modes (XFS_AFCS_FD_MODE_*

      Parameter ID: %x00.00.9a
      Unit Usage: FD Number (0 for setting values)
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using afcs_fd_mode dictionary (See Table 61.)

4.7.157.  ALTHOLDBUG - Altitude used by FD for altitude hold

      Parameter ID: %x00.00.9b
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: FT multiplied by 10.

4.7.158.  APMODE - Autopilot Modes

      Parameter ID: %x00.00.9c
      Unit Usage: AP Number (0 for setting value)
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using afcs_ap_mode dictionary (See Table 62.)

   Table 62, below, shows the values defined in the afcs-ap-mode
   Dictionary.  These options represent the Vertical, lateral and yaw
   modes of autopilot and throttle.





















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      +============+===============+================================+
      | Name       | Value         | Definition                     |
      +============+===============+================================+
      | VERT-MASK  | %xff          | Vertical modes mask            |
      +------------+---------------+--------------------------------+
      | LAT-MASK   | %xff.00       | Lateral modes mask             |
      +------------+---------------+--------------------------------+
      | THROT-MASK | %xff.00.00    | Throttle modes mask            |
      +------------+---------------+--------------------------------+
      | YAW-MASK   | %xff.00.00.00 | Yaw modes mask                 |
      +------------+---------------+--------------------------------+
      | PITCH      | %x01          | Pitch mode                     |
      +------------+---------------+--------------------------------+
      | EPPITCH    | %x02          | Pitch mode only for envelope   |
      |            |               | protection                     |
      +------------+---------------+--------------------------------+
      | ROLL       | %x01.00       | Roll mode                      |
      +------------+---------------+--------------------------------+
      | EPROLL     | %x02.00       | Roll mode only for envelope    |
      |            |               | protection                     |
      +------------+---------------+--------------------------------+
      | SPD        | %x01.00.00    | Activate autothrottle speed    |
      |            |               | tracking                       |
      +------------+---------------+--------------------------------+
      | EPSPD      | %x02.00.00    | Autothrottle only for envelope |
      |            |               | protection (SPD mode)          |
      +------------+---------------+--------------------------------+
      | AOA        | %x04.00.00    | Activate autothrottle AoA      |
      |            |               | tracking                       |
      +------------+---------------+--------------------------------+
      | EPAOA      | %x08.00.00    | Autothrottle only for envelope |
      |            |               | protection (AOA mode)          |
      +------------+---------------+--------------------------------+
      | TOGA       | %x10.00.00    | Activate takeoff / go-around   |
      |            |               | throttle                       |
      +------------+---------------+--------------------------------+
      | EPTOGA     | %x20.00.00    | Autothrottle only for envelope |
      |            |               | protection (TOGA mode)         |
      +------------+---------------+--------------------------------+
      | YAW        | %x01.00.00.00 | Yaw mode                       |
      +------------+---------------+--------------------------------+
      | EPYAW      | %x02.00.00.00 | Yaw envelope protection        |
      +------------+---------------+--------------------------------+

                     Table 62: afcs-ap-mode Dictionary

4.7.159.  ICSSQL - Intercom Squelch (0-100)




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      Parameter ID: %x00.00.9d
      Unit Usage: Audio Panel Unit
      SubUnit Usage: 0=System, 1=Pilot, 2=Copilot, rest are pax
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: PERCENT (See Section 4.5.2.4.)
      Units: PCENT.

4.7.160.  PITCHBUG - Target pitch

      Parameter ID: %x00.00.9e
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: PITCH (See Section 4.5.2.3.)
      Units: DEG multiplied by 100.

4.7.161.  PTSPEED - Power Turbine Speed (commonly N1)

      Parameter ID: %x00.00.9f
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PCENT multiplied by 1000.

4.7.162.  GTSPEED - Gas Turbine Speed (commonly N2 or Ng)

      Parameter ID: %x00.00.a0
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PCENT multiplied by 1000.

4.7.163.  TIT - Turbine Inlet Temperature

      Parameter ID: %x00.00.a1
      Unit Usage: Engine
      SubUnit Usage: Turbo/0=Max
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.164.  ITT - Inter-Turbine Temperature

      Parameter ID: %x00.00.a2



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      Unit Usage: Engine
      SubUnit Usage: Sensor/0=Average
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.165.  POWER - Power under current engine and environmental
          conditions relative to engine design maximum

      Parameter ID: %x00.00.a3
      Unit Usage: Motor/Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: SERVO (See Section 4.5.2.1.)
      Units: PCENT multiplied by 1000.

4.7.166.  ENGSTATUS - Engine specific set of flags or values

      Parameter ID: %x00.00.a4
      Unit Usage: Motor/Engine
      SubUnit Usage: Engine Specific
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using hex dictionary (See Table 60.)

4.7.167.  CABINALT - Cabin Equivalent Altitude

      Parameter ID: %x00.00.a5
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: FT multiplied by 10.

4.7.168.  CABINALTREQ - Cabin Equivalent Altitude

      Parameter ID: %x00.00.a6
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: FT multiplied by 10.

4.7.169.  DIFFPRES - Differential Pressure

      Parameter ID: %x00.00.a7
      Unit Usage: None



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      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PSI multiplied by 100.

4.7.170.  DIFFPRESREQ - Requested Differential Pressure

      Parameter ID: %x00.00.a8
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PSI multiplied by 100.

4.7.171.  FUELTEMP - Arbitraty Temperature in a location

      Parameter ID: %x00.00.a9
      Unit Usage: Engine/Fuel Tank
      SubUnit Usage: SubLocation/0=Average,1=Sump
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.172.  ENGSTATE - Engine operating state

      Parameter ID: %x00.00.aa
      Unit Usage: Motor/Engine
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using engstate dictionary (See Table 63.)

   Table 63, below, shows the values defined in the engstate Dictionary.
   These options represent the States of engines.

















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      +=================+============+=============================+
      | Name            | Value      | Definition                  |
      +=================+============+=============================+
      | UNKNOWN         | %x00       | Engine Status Unknown       |
      +-----------------+------------+-----------------------------+
      | OFF             | %x01       | Engine is Off               |
      +-----------------+------------+-----------------------------+
      | DRYMOTOR        | %x02       | Engine Starting             |
      +-----------------+------------+-----------------------------+
      | STARTING        | %x03       | Engine Starting             |
      +-----------------+------------+-----------------------------+
      | RUNNING         | %x04       | Engine Running Normally     |
      +-----------------+------------+-----------------------------+
      | FLAMEOUT        | %x05       | Engine Flamed Out / Failure |
      +-----------------+------------+-----------------------------+
      | SHUTDOWN        | %x06       | Engine Shutting Down        |
      +-----------------+------------+-----------------------------+
      | SHUTOFF         | %x07       | Engine Shut Off             |
      +-----------------+------------+-----------------------------+
      | MODE-MASK       | %xff       | Mask for Engine State       |
      +-----------------+------------+-----------------------------+
      | FLAG-IGNITION   | %x01.00    | Ignition On                 |
      +-----------------+------------+-----------------------------+
      | FLAG-FUEL       | %x02.00    | Fuel Shutoff Open           |
      +-----------------+------------+-----------------------------+
      | FLAG-STARTER    | %x04.00    | Starter On                  |
      +-----------------+------------+-----------------------------+
      | FLAG-GENERATOR  | %x08.00    | Generator On                |
      +-----------------+------------+-----------------------------+
      | FLAG-BLEED      | %x10.00    | Bleed Air On                |
      +-----------------+------------+-----------------------------+
      | FLAG-FIRE       | %x01.00.00 | Fire Present                |
      +-----------------+------------+-----------------------------+
      | FLAG-EXTINGUISH | %x02.00.00 | Extinguisher Dispensed      |
      +-----------------+------------+-----------------------------+

                      Table 63: engstate Dictionary

4.7.173.  ENGSTATEREQ - Requested Engine operating state

      Parameter ID: %x00.00.ab
      Unit Usage: Motor/Engine
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using engstate dictionary (See Table 63.)





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4.7.174.  BLEEDAIR - Bleed Air Level (Percent of Max)

      Parameter ID: %x00.00.ac
      Unit Usage: Motor/Engine
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: PCENT multiplied by 100.

4.7.175.  BLEEDAIRREQ - Requested Bleed Air Level

      Parameter ID: %x00.00.ad
      Unit Usage: Motor/Engine
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: PCENT multiplied by 100.

4.7.176.  LIGHTING - Lighting Color/Level

      Parameter ID: %x00.00.ae
      Unit Usage: System
      SubUnit Usage: Specific
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: RGBA.

4.7.177.  LIGHTINGREQ - Requested Lighting Color/Level

      Parameter ID: %x00.00.af
      Unit Usage: System
      SubUnit Usage: Specific
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: RGBA.

4.7.178.  ICING - Deicing State

      Parameter ID: %x00.00.b0
      Unit Usage: System/0=Aircraft
      SubUnit Usage: Specific
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using icing_flag dictionary (See Table 64.)

   Table 64, below, shows the values defined in the icing-flag
   Dictionary.  These options represent the Status of ice detection,
   anti-ice and deicing systems.



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   +=================+===============+================================+
   | Name            | Value         | Definition                     |
   +=================+===============+================================+
   | ENGINE          | %x01          | Engine Deicing/Anticing On     |
   +-----------------+---------------+--------------------------------+
   | AIRFRAME        | %x02          | Airframe Deicing/Anticing On   |
   +-----------------+---------------+--------------------------------+
   | INSEP           | %x04          | Inertial Separator Activated   |
   +-----------------+---------------+--------------------------------+
   | PITOT           | %x08          | Pitot/Static Heat Activated    |
   +-----------------+---------------+--------------------------------+
   | PROPHEAT        | %x10          | Propeller Heat Activated       |
   +-----------------+---------------+--------------------------------+
   | WINDHEAT        | %x20          | Windshield Heat Activated      |
   +-----------------+---------------+--------------------------------+
   | CARBHEAT        | %x40          | Carb Heat Activated            |
   +-----------------+---------------+--------------------------------+
   | CARBICEDET      | %x40.00       | Carb Icing Detected            |
   +-----------------+---------------+--------------------------------+
   | ICEDET          | %x80.00       | Icing Detected                 |
   +-----------------+---------------+--------------------------------+
   | ENGINE-FAIL     | %x01.00.00    | Engine Deicing/Anticing Failed |
   +-----------------+---------------+--------------------------------+
   | AIRFRAME-FAIL   | %x02.00.00    | Airframe Deicing/Anticing      |
   |                 |               | Failed                         |
   +-----------------+---------------+--------------------------------+
   | INSEP-FAIL      | %x04.00.00    | Inertial Separator Failed      |
   +-----------------+---------------+--------------------------------+
   | PITOT-FAIL      | %x08.00.00    | Pitot/Static Heat Failed       |
   +-----------------+---------------+--------------------------------+
   | PROPHEAT-FAIL   | %x10.00.00    | Propeller Heat Failed          |
   +-----------------+---------------+--------------------------------+
   | WINDHEAT-FAIL   | %x20.00.00    | Windshield Heat Failed         |
   +-----------------+---------------+--------------------------------+
   | CARBHEAT-FAIL   | %x40.00.00    | Carb Heat Failed               |
   +-----------------+---------------+--------------------------------+
   | CARBICEDET-FAIL | %x40.00.00.00 | Carb Icing Detection Failed    |
   +-----------------+---------------+--------------------------------+
   | ICEDET-FAIL     | %x80.00.00.00 | Icing Detection Failed         |
   +-----------------+---------------+--------------------------------+

                     Table 64: icing-flag Dictionary

4.7.179.  ICINGREQ - Requested Deicing State

      Parameter ID: %x00.00.b1
      Unit Usage: System/0=Aircraft
      SubUnit Usage: Specific



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      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using icing_flag dictionary (See Table 64.)

4.7.180.  LDGGEAR - Landing Gear State

      Parameter ID: %x00.00.b2
      Unit Usage: Wheel/0=Aircraft
      SubUnit Usage: Specific
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using ldggear dictionary (See Table 65.)

   Table 65, below, shows the values defined in the ldggear Dictionary.
   These options represent the Status of retractable landing gear.

       +=============+============+===============================+
       | Name        | Value      | Definition                    |
       +=============+============+===============================+
       | UNKNOWN     | %x00.00    | Gear Status Unknown           |
       +-------------+------------+-------------------------------+
       | DOWN        | %x00.01    | Landing Gear Down             |
       +-------------+------------+-------------------------------+
       | UP          | %x80.00    | Landing Gear Up               |
       +-------------+------------+-------------------------------+
       | FLAG-FAILED | %x01.00.00 | Landing Gear System is Failed |
       +-------------+------------+-------------------------------+

                       Table 65: ldggear Dictionary

4.7.181.  LDGGEARREQ - Landing Gear State

      Parameter ID: %x00.00.b3
      Unit Usage: Wheel/0=Aircraft
      SubUnit Usage: Specific
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using ldggear dictionary (See Table 65.)

4.7.182.  CABINTEMP - Cabin Temperature in a zone

      Parameter ID: %x00.00.b4
      Unit Usage: Zone
      SubUnit Usage: Sensor Number/0=Average
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: C multiplied by 100.




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4.7.183.  CABINTEMPREQ - Requested Cabin Temperature in a zone

      Parameter ID: %x00.00.b5
      Unit Usage: Zone
      SubUnit Usage: Sensor Number/0=Average
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: C multiplied by 100.

4.7.184.  CHKLIST - Checklist Item

      Parameter ID: %x00.00.b6
      Unit Usage: Checklist Number
      SubUnit Usage: Item Number/0=Title
      Format: CASMSG (See Table 32.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.185.  WBARM - Arm for selected station or aircraft

      Parameter ID: %x00.00.b7
      Unit Usage: Configuration
      SubUnit Usage: 0=total/1=total no fuel/2+=station
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.

4.7.186.  WBCONFIG - Selected aircraft configuration for weight and
          balance

      Parameter ID: %x00.00.b8
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.

4.7.187.  WBCATEGORY - Weight and balance aircraft category

      Parameter ID: %x00.00.b9
      Unit Usage: Configuration
      SubUnit Usage: 0=total/1=total no fuel
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using weightbal_category dictionary (See
      Table 66.)

   Table 66, below, shows the values defined in the weightbal-category
   Dictionary.  These options represent the Aircraft operational
   categories.




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                +===========+=======+====================+
                | Name      | Value | Definition         |
                +===========+=======+====================+
                | NORMAL    | %d1   | Normal Category    |
                +-----------+-------+--------------------+
                | UTILITY   | %d2   | Utility Category   |
                +-----------+-------+--------------------+
                | ACROBATIC | %d3   | Acrobatic Category |
                +-----------+-------+--------------------+
                | COMMUTER  | %d4   | Commuter Category  |
                +-----------+-------+--------------------+

                 Table 66: weightbal-category Dictionary

4.7.188.  WBSTATUS - Flags about weight and balance

      Parameter ID: %x00.00.ba
      Unit Usage: Configuration
      SubUnit Usage: 0=total/1=total no fuel
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using weightbal_status dictionary (See
      Table 67.)

   Table 67, below, shows the values defined in the weightbal-status
   Dictionary.  These options represent the Weight and balance status.

























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            +===========+=======+============================+
            | Name      | Value | Definition                 |
            +===========+=======+============================+
            | OK        | %d0   | Weight and balance is OK   |
            +-----------+-------+----------------------------+
            | FWD       | %x01  | Balance is forward of      |
            |           |       | minimum CG for this weight |
            +-----------+-------+----------------------------+
            | AFT       | %x02  | Balance is aft of maximum  |
            |           |       | CG for this weight         |
            +-----------+-------+----------------------------+
            | OVWTSTATN | %x04  | One or more stations are   |
            |           |       | overweight                 |
            +-----------+-------+----------------------------+
            | OVERMGTOW | %x08  | Weight exceeds maximum     |
            |           |       | gross takeoff weight       |
            +-----------+-------+----------------------------+
            | OVERMLW   | %x10  | Weight exceeds max landing |
            |           |       | weight                     |
            +-----------+-------+----------------------------+
            | OVERZFW   | %x20  | Weight exceeds max zero    |
            |           |       | fuel weight                |
            +-----------+-------+----------------------------+

                  Table 67: weightbal-status Dictionary

4.7.189.  WBWEIGHT - Aircraft or station weight

      Parameter ID: %x00.00.bb
      Unit Usage: Configuration
      SubUnit Usage: 0=total/1=total no fuel/2+=station
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: LB multiplied by 10.

4.7.190.  TASEFFWT - Fuel Economy Relative to True Airspeed and Weight

      Parameter ID: %x00.00.bc
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: NMPLB multiplied by 100000.

4.7.191.  GSEFFWT - Fuel Economy Relative to Groundspeed and Weight

      Parameter ID: %x00.00.bd
      Unit Usage: None



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      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: NMPLB multiplied by 100000.

4.7.192.  TIMETOEMPTY - Time to Empty

      Parameter ID: %x00.00.be
      Unit Usage: Engine/0=Aircraft
      SubUnit Usage: 0 - smoothed, without reserve, 1 - smoothed, with
      reserve, 2 - without reserve, 3 - with reserve
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: S multiplied by 10.

4.7.193.  DISTTOEMPTY - Distance to Empty

      Parameter ID: %x00.00.bf
      Unit Usage: Engine/0=Aircraft
      SubUnit Usage: 0 - smoothed, without reserve, 1 - smoothed, with
      reserve, 2 - without reserve, 3 - with reserve
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: NM multiplied by 100.

4.7.194.  FLIGHTSTATE - State of Flight

      Parameter ID: %x00.00.c0
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using flight_state dictionary (See Table 68.)

   Table 68, below, shows the values defined in the flight-state
   Dictionary.  These options represent the Status of aircraft within
   flight profile.

    +===============+=======+=========================================+
    | Name          | Value | Definition                              |
    +===============+=======+=========================================+
    | UNKNOWN       | %d0   | The state of the aircraft is not known  |
    +---------------+-------+-----------------------------------------+
    | OFF           | %d1   | The aircraft is completely powered down |
    +---------------+-------+-----------------------------------------+
    | HIBERNATE     | %d2   | Minimal aircraft systems online not     |
    |               |       | visible to the pilot                    |
    +---------------+-------+-----------------------------------------+



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    | PREFLIGHT     | %d3   | Minimal aircraft systems for pilot      |
    |               |       | interaction online                      |
    +---------------+-------+-----------------------------------------+
    | ENGINE-START  | %d4   | Engine(s) are preparing to start or are |
    |               |       | starting                                |
    +---------------+-------+-----------------------------------------+
    | PRETAXI       | %d5   | Engine(s) are started, awaiting pre-    |
    |               |       | taxi items                              |
    +---------------+-------+-----------------------------------------+
    | TAXI          | %d6   | Aircraft is ready or in process of      |
    |               |       | taxiing                                 |
    +---------------+-------+-----------------------------------------+
    | RUNUP         | %d7   | Aircraft is ready for, or in process of |
    |               |       | performing runup                        |
    +---------------+-------+-----------------------------------------+
    | READY         | %d8   | Aircraft is ready for and positioned    |
    |               |       | just short of takeoff                   |
    +---------------+-------+-----------------------------------------+
    | TAKEOFF       | %d9   | Aircraft is in process of performing    |
    |               |       | takeoff                                 |
    +---------------+-------+-----------------------------------------+
    | AFTER-TAKEOFF | %d10  | Aircraft is airborne immediately but    |
    |               |       | not yet configured for normal climb     |
    +---------------+-------+-----------------------------------------+
    | DEPARTURE     | %d11  | Aircraft is on a standard instrument    |
    |               |       | departure                               |
    +---------------+-------+-----------------------------------------+
    | CLIMB         | %d12  | Aircraft is climbing but not on an      |
    |               |       | instrument departure                    |
    +---------------+-------+-----------------------------------------+
    | CRUISE        | %d13  | Aircraft is at final cruise             |
    +---------------+-------+-----------------------------------------+
    | DESCENT       | %d14  | Aircraft is descending not on a         |
    |               |       | standard arrival                        |
    +---------------+-------+-----------------------------------------+
    | ARRIVAL       | %d15  | Aircraft is on a standard arrival       |
    +---------------+-------+-----------------------------------------+
    | APPROACH      | %d16  | Aircraft is on an instrument approach   |
    |               |       | procedure                               |
    +---------------+-------+-----------------------------------------+
    | VISUAL        | %d17  | Aircraft is flying a visual traffic     |
    |               |       | pattern                                 |
    +---------------+-------+-----------------------------------------+
    | MISSED        | %d18  | Aircraft is executing a missed approach |
    +---------------+-------+-----------------------------------------+
    | SHUTDOWN      | %d19  | Aircraft engines are shutting down or   |
    |               |       | have shut down                          |
    +---------------+-------+-----------------------------------------+



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    | SECURE        | %d20  | Aircraft systems are shutting down or   |
    |               |       | reconfiguring for preflight             |
    +---------------+-------+-----------------------------------------+

                     Table 68: flight-state Dictionary

4.7.195.  UPDATESTATE - Status of any update

      Parameter ID: %x00.00.c1
      Unit Usage: None
      SubUnit Usage: None
      Format: UPDATE (See Table 45.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.196.  TORQUEREQ - Requested Torque

      Parameter ID: %x00.00.c2
      Unit Usage: Motor/Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: LBFT multiplied by 100.

4.7.197.  STKPITCHFRCE - Stick Pitch Force applied by the pilot,
          positive value - push, negative value - pull

      Parameter ID: %x00.00.c3
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: LB multiplied by 100.

4.7.198.  STKROLLFRCE - Stick Roll Force applied by the pilot, positive
          value - roll right, negative value - roll left

      Parameter ID: %x00.00.c4
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: LB multiplied by 100.

4.7.199.  STKYAWFRCE - Pedal Yaw Force applied by the pilot, positive
          value - right rudder, negative value - left rudder

      Parameter ID: %x00.00.c5
      Unit Usage: None



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      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: LB multiplied by 100.

4.7.200.  APPITCHFRCE - Auto Pilot Pitch Force exerted on control
          surfaces, positive value - push, negative value - pull

      Parameter ID: %x00.00.c6
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: LB multiplied by 100.

4.7.201.  APROLLFRCE - Auto Pilot Roll Force exerted on control
          surfaces, positive value - roll right, negative value - roll
          left

      Parameter ID: %x00.00.c7
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: LB multiplied by 100.

4.7.202.  APYAWFRCE - Auto Pilot Yaw Force exerted on control surfaces,
          positive value - right rudder, negative value - left rudder

      Parameter ID: %x00.00.c8
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: LB multiplied by 100.

4.7.203.  EFBPARAM - Up to 64-character, NULL terminated parameter value

      Parameter ID: %x00.00.c9
      Unit Usage: EFB ID
      SubUnit Usage: XFS_EFB_PARAM_*
      Format: STRING (See Table 31.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.204.  OILPRESCOMP - Compensated Oil Pressure

      Parameter ID: %x00.00.ca
      Unit Usage: Engine



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      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PSI multiplied by 100.

4.7.205.  MACHBUG - Target Mach

      Parameter ID: %x00.00.cb
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: MACH multiplied by 10000.

4.7.206.  AOART - Angle of attack rate of change

      Parameter ID: %x00.00.cc
      Unit Usage: Source
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: DEG multiplied by 1000.

4.7.207.  TASBUG - Target true airspeed

      Parameter ID: %x00.00.cd
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.208.  GSBUG - Target groundspeed

      Parameter ID: %x00.00.ce
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.209.  AOABUG - Bugged AOA

      Parameter ID: %x00.00.cf
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.



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      Units: DEG multiplied by 1000.

4.7.210.  ECUTIME - ECU Hours

      Parameter ID: %x00.00.d1
      Unit Usage: Engine
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: HR multiplied by 1000.

4.7.211.  DBASE - Active database information

      Parameter ID: %x00.00.d2
      Unit Usage: CPU ID
      SubUnit Usage: Process ID
      Format: DBASE (See Table 49.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.212.  EAS - Equivalent Airspeed

      Parameter ID: %x00.00.d3
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.213.  EASRT - Equivalent Airspeed Rate of Change

      Parameter ID: %x00.00.d4
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KTPS multiplied by 100.

4.7.214.  EASBUG - Target equivalent airspeed

      Parameter ID: %x00.00.d5
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.215.  POWERREQ - Requested power as percent of engine design maximum




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      Parameter ID: %x00.00.d6
      Unit Usage: Motor/Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: PCENT multiplied by 1000.

4.7.216.  BRAKE - Wheel brake status

      Parameter ID: %x00.00.d7
      Unit Usage: Left=1,Right=2,No direction=0
      SubUnit Usage: Specific
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using brake dictionary (See Table 69.)

   Table 69, below, shows the values defined in the brake Dictionary.
   These options represent the Status of wheel brakes.

           +=============+============+========================+
           | Name        | Value      | Definition             |
           +=============+============+========================+
           | UNKNOWN     | %x00.00    | Brake Status Unknown   |
           +-------------+------------+------------------------+
           | NONE        | %x00.01    | Brakes not pressed     |
           +-------------+------------+------------------------+
           | MAX         | %x80.00    | Max Braking            |
           +-------------+------------+------------------------+
           | PARK        | %x01.00.00 | Parking Brake Engaged  |
           +-------------+------------+------------------------+
           | FLAG-FAILED | %x02.00.00 | Brake System is Failed |
           +-------------+------------+------------------------+

                         Table 69: brake Dictionary

4.7.217.  BRAKEREQ - Amount of brake requested

      Parameter ID: %x00.00.d8
      Unit Usage: Left=1,Right=2,No direction=0
      SubUnit Usage: Specific
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using brake dictionary (See Table 69.)

4.7.218.  NAVSQL - Communication Squelch (0-100)

      Parameter ID: %x00.00.d9
      Unit Usage: Radio ID



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      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Default Range: PERCENT (See Section 4.5.2.4.)
      Units: PCENT.

4.7.219.  STATIONID - VOR Station ID decoded from Morse code

      Parameter ID: %x00.00.da
      Unit Usage: Radio ID
      SubUnit Usage: None
      Format: STRING (See Table 31.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.220.  SVPARAM - Synthetic Vision parameters.  Subunit is one of
          XFS_SV_PARAM_*

      Parameter ID: %x00.00.db
      Unit Usage: SYNVIS ID
      SubUnit Usage: XFS_SV_PARAM_*
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.221.  FDCDISEL - Global selection of which CDI the flight director
          should track

      Parameter ID: %x00.00.dc
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.222.  BLOODOXY - Blood oxygen level of given seat occupant

      Parameter ID: %x00.00.dd
      Unit Usage: Seat position, 0=Lowest of all seats, 1=Pilot,
      2=Copilot, etc
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Default Range: THOUPERCENT (See Section 4.5.2.5.)
      Units: PCENT multiplied by 1000.

4.7.223.  PULSE - Pulse rate of given seat occupant

      Parameter ID: %x00.00.de
      Unit Usage: Seat position, 0=Worst of all seats (too low or high),
      1=Pilot, 2=Copilot, etc



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      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: CPM multiplied by 1000.

4.7.224.  BREATHS - Breathing rate of given seat occupant

      Parameter ID: %x00.00.df
      Unit Usage: Seat position, 0=Worst of all seats (too low or high),
      1=Pilot, 2=Copilot, etc
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: CPM multiplied by 1000.

4.7.225.  CARBMONOX - Carbon Monoxide levels detected by sensor

      Parameter ID: %x00.00.e0
      Unit Usage: Carbon Monoxide Sensor ID
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PPM multiplied by 100.

4.7.226.  FLOWRATE - Oxygen flow rate

      Parameter ID: %x00.00.e1
      Unit Usage: Seat position, 0=Worst of all seats (too low or high),
      1=Pilot, 2=Copilot, etc
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: LPM multiplied by 100.

4.7.227.  TANKPRES - Oxygen tank pressure

      Parameter ID: %x00.00.e2
      Unit Usage: Tank number, 0=Worst of all tanks (too low or high),
      1=Tank 1, 2=Tank 2, etc
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: PSI multiplied by 100.

4.7.228.  RNAVVS - Vertical speed computed from RNAV

      Parameter ID: %x00.00.e3
      Unit Usage: Source ID



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      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: FPM multiplied by 1.

4.7.229.  COMPRESET - Selected COM Radio Preset (0=Non-preset frequency)

      Parameter ID: %x00.00.e4
      Unit Usage: Radio
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Values interpreted using preset dictionary (See Table 70.)

   Table 70, below, shows the values defined in the preset Dictionary.
   These options represent the XFS Preset Frequency.

             +========+=========+===========================+
             | Name   | Value   | Definition                |
             +========+=========+===========================+
             | MANUAL | %d0     | Manual Tuning (no preset) |
             +--------+---------+---------------------------+
             | LAST   | %xff.fe | Last selected frequency   |
             +--------+---------+---------------------------+

                       Table 70: preset Dictionary

4.7.230.  COMNAME - Name of COM Radio or Preset Frequency

      Parameter ID: %x00.00.e5
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: STRING (See Table 31.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.231.  NAVPRESET - Selected NAV Radio Preset (0=Non-preset frequency)

      Parameter ID: %x00.00.e6
      Unit Usage: Radio
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Values interpreted using preset dictionary (See Table 70.)

4.7.232.  NAVNAME - Name of NAV Radio or Preset Frequency

      Parameter ID: %x00.00.e7
      Unit Usage: Radio



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      SubUnit Usage: 0=Radio/1+=Presets
      Format: STRING (See Table 31.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.233.  VNORTH - North component of velocity in true world coordinates

      Parameter ID: %x00.00.e8
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.234.  VEAST - East component of velocity in true world coordinates

      Parameter ID: %x00.00.e9
      Unit Usage: Source ID
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: KT multiplied by 100.

4.7.235.  ENGPOWER - Current Engine Power

      Parameter ID: %x00.00.ea
      Unit Usage: Engine
      SubUnit Usage: 0=Shaft Power/1=Input Power
      Consumption/2+(even)=Component Shaft Power, 3+(odd)=Component
      Power Consumption
      Format: UINT (See Table 26.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: KW multiplied by 1000.

4.7.236.  CHARGE - Measured remaining battery charge

      Parameter ID: %x00.00.eb
      Unit Usage: Battery ID/0=Sum of all
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: AH multiplied by 1000.

4.7.237.  CHARGETOT - Computed remaining charge

      Parameter ID: %x00.00.ec
      Unit Usage: Power System ID/0=Sum of all
      SubUnit Usage: 0 = current total, 1 = total at end of flight
      Format: SINT (See Table 35.)



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      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: AH multiplied by 1000.

4.7.238.  RWYSEL - Select airport runway surface to waypoint that is an
          airport, subunit is position in flightplan (SYSSEL/USERSEL
          ONLY).  Label must match

      Parameter ID: %x00.00.ed
      Unit Usage: None
      SubUnit Usage: None
      Format: WAYPOINT (See Table 27.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.239.  COMSECMODE - Communication Security Mode

      Parameter ID: %x00.00.ee
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using com_secmode dictionary (See Table 71.)

   Table 71, below, shows the values defined in the com-secmode
   Dictionary.  These options represent the Communication Security Mode.

                  +=========+=======+==================+
                  | Name    | Value | Definition       |
                  +=========+=======+==================+
                  | TD      | %d1   | TD               |
                  +---------+-------+------------------+
                  | PT      | %d2   | Plain Text       |
                  +---------+-------+------------------+
                  | CT      | %d7   | Cypher Text      |
                  +---------+-------+------------------+
                  | INVALID | %d8   | Invalid Reserved |
                  +---------+-------+------------------+
                  | RV      | %d14  | RV               |
                  +---------+-------+------------------+

                     Table 71: com-secmode Dictionary

4.7.240.  COMBAND - Communication Band

      Parameter ID: %x00.00.ef
      Unit Usage: None
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.



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      Values interpreted using com_band dictionary (See Table 72.)

   Table 72, below, shows the values defined in the com-band Dictionary.
   These options represent the Communication Band.

    +=========+=======+===============================================+
    | Name    | Value | Definition                                    |
    +=========+=======+===============================================+
    | UNKNOWN | %d0   | Unknown communication band                    |
    +---------+-------+-----------------------------------------------+
    | VHFFM   | %d1   | Very High Frequency with Frequency Modulation |
    +---------+-------+-----------------------------------------------+
    | VHFAM   | %d2   | Very High Frequency Amplitude Modulation      |
    +---------+-------+-----------------------------------------------+
    | UHFFM   | %d3   | Ultra High Frequency                          |
    +---------+-------+-----------------------------------------------+
    | UHFAM   | %d4   | Ultra High Frequency                          |
    +---------+-------+-----------------------------------------------+
    | P25A    | %d5   | Project 25 Analog                             |
    +---------+-------+-----------------------------------------------+
    | P25D    | %d6   | Project 25 Digital                            |
    +---------+-------+-----------------------------------------------+
    | P25T    | %d7   | Project 25 Trunk Mode                         |
    +---------+-------+-----------------------------------------------+
    | TSM     | %d8   | Trellisware Scalable Mobile Ad-hoc NETworking |
    +---------+-------+-----------------------------------------------+
    | SATCOM  | %d9   | Satellite Communication                       |
    +---------+-------+-----------------------------------------------+
    | SNGRS   | %d10  | SINCGARS Frequency Hop Frequencies            |
    +---------+-------+-----------------------------------------------+
    | HFAM    | %d11  | High Frequency Ampltitude Modulation          |
    +---------+-------+-----------------------------------------------+
    | WREN    | %d12  | Warrior Robust Enhanced Network Narrowband    |
    +---------+-------+-----------------------------------------------+

                       Table 72: com-band Dictionary

4.7.241.  COMBANDMASK - Supported Communication Bands

      Parameter ID: %x00.00.f0
      Unit Usage: Radio
      SubUnit Usage: None
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using com_bandmask dictionary (See Table 73.)






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   Table 73, below, shows the values defined in the com-bandmask
   Dictionary.  These options represent the Supported Communication Band
   Mask.

            +==========+=========+===========================+
            | Name     | Value   | Definition                |
            +==========+=========+===========================+
            | VHFFM    | %x01    | Very High Frequency with  |
            |          |         | Frequency Modulation      |
            +----------+---------+---------------------------+
            | VHFAM    | %x02    | Very High Frequency with  |
            |          |         | Amplitude Modulation      |
            +----------+---------+---------------------------+
            | UHFFM    | %x04    | Ultra High Frequency with |
            |          |         | Frequency Modulation      |
            +----------+---------+---------------------------+
            | UHFAM    | %x08    | Ultra High Frequency with |
            |          |         | Amplitude Modulation      |
            +----------+---------+---------------------------+
            | P25A     | %x10    | Project 25 Analog         |
            +----------+---------+---------------------------+
            | P25D     | %x20    | Project 25 Digital        |
            +----------+---------+---------------------------+
            | P25T     | %x40    | Project 25 Trunk Mode     |
            +----------+---------+---------------------------+
            | TSM      | %x80    | Trellisware Scalable      |
            |          |         | Mobile Ad-hoc NETworking  |
            +----------+---------+---------------------------+
            | SATCOM   | %x01.00 | Satellite Communication   |
            +----------+---------+---------------------------+
            | SINCGARS | %x02.00 | SINCGARS Frequency Hop    |
            |          |         | Frequencies               |
            +----------+---------+---------------------------+
            | HFAM     | %x04.00 | High Frequency            |
            +----------+---------+---------------------------+

                    Table 73: com-bandmask Dictionary

4.7.242.  COMSQLMODETX - Squelch mode for transmit

      Parameter ID: %x00.00.f1
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using com_sqlmode dictionary (See Table 74.)





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   Table 74, below, shows the values defined in the com-sqlmode
   Dictionary.  These options represent the Communication Squelch Mode.

        +=========+=======+======================================+
        | Name    | Value | Definition                           |
        +=========+=======+======================================+
        | UNKNOWN | %d0   | Unknown Squelch Mode                 |
        +---------+-------+--------------------------------------+
        | NONE    | %d1   | Squelch Off                          |
        +---------+-------+--------------------------------------+
        | SNR     | %d2   | Signal to Noise Ratio                |
        +---------+-------+--------------------------------------+
        | TONE    | %d3   | FM Military Tone Squelch System      |
        +---------+-------+--------------------------------------+
        | CTCSS   | %d4   | Continuous Tone Coded Squelch System |
        +---------+-------+--------------------------------------+
        | DCS     | %d5   | Digital Code Squelch                 |
        +---------+-------+--------------------------------------+
        | NAC     | %d6   | Network Access Code P25 Trunk Mode   |
        +---------+-------+--------------------------------------+

                     Table 74: com-sqlmode Dictionary

4.7.243.  COMSQLMODERX - Squelch mode for receive

      Parameter ID: %x00.00.f2
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Values interpreted using com_sqlmode dictionary (See Table 74.)

4.7.244.  COMCTCSSTX - Frequency for CTCSS in Analog Transmit

      Parameter ID: %x00.00.f3
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.245.  COMCTCSSRX - Frequency for CTCSS in Analog Receive

      Parameter ID: %x00.00.f4
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.




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4.7.246.  COMDCSTX - Digital-Coded Squelch in Digital Transmit

      Parameter ID: %x00.00.f5
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.247.  COMDCSRX - Digital-Coded Squelch in Digital Receive

      Parameter ID: %x00.00.f6
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.248.  COMNACTX - Network Access Code in P25 Digital Transmit

      Parameter ID: %x00.00.f7
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.249.  COMNACRX - Network Access Code in P25 Digital Receive

      Parameter ID: %x00.00.f8
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.250.  COMSPACING - Communication Frequency Spacing

      Parameter ID: %x00.00.f9
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: MHZ multiplied by 100000.

4.7.251.  COMTGROUP - Active Communication Talk Group

      Parameter ID: %x00.00.fa
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: UINT (See Table 26.)
      Range: There SHALL NOT be a Range Parameter for this parameter.



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4.7.252.  COMTGROUPR - Range for Talk Groups

      Parameter ID: %x00.00.fb
      Unit Usage: Radio
      SubUnit Usage: None
      Format: RANGE (See Table 39.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.253.  COMTGNAME - Name of Talk Group

      Parameter ID: %x00.00.fc
      Unit Usage: Radio
      SubUnit Usage: 0=radio active talk group, 1+= talkgroup name
      Format: STRING (See Table 31.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.254.  COMGUARD - If true monitor guard frequency

      Parameter ID: %x00.00.fd
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: BOOL (See Table 24.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.255.  COMENCRYPT - If true, radio is operating in encrypted mode

      Parameter ID: %x00.00.fe
      Unit Usage: Radio
      SubUnit Usage: 0=Radio/1+=Presets
      Format: BOOL (See Table 24.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

4.7.256.  FUELVOLTOT - Computed remaining fuel volume

      Parameter ID: %x00.00.ff
      Unit Usage: Fuel System ID/0=Sum of all
      SubUnit Usage: 0 = current total, 1 = total at end of flight
      Format: SINT (See Table 35.)
      Range: There SHALL NOT be a Range Parameter for this parameter.
      Units: GAL multiplied by 1000.

4.7.257.  FUELVOLFLOW - Fuel Flow by Volume

      Parameter ID: %x00.01.00
      Unit Usage: Engine
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.



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      Units: GPH multiplied by 1000.

4.7.258.  FUELVOL - Fuel Volume

      Parameter ID: %x00.01.01
      Unit Usage: Fuel Tank ID/0=Sum of all
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: GAL multiplied by 1000.

4.7.259.  TASEFFVOL - Fuel Economy Relative to True Airspeed and Volume

      Parameter ID: %x00.01.02
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: NMPGAL multiplied by 1000000.

4.7.260.  GSEFFVOL - Fuel Economy Relative to Groundspeed and Volume

      Parameter ID: %x00.01.03
      Unit Usage: None
      SubUnit Usage: None
      Format: SINT (See Table 35.)
      Range: There SHALL be a Range Parameter for this parameter.
      Units: NMPGAL multiplied by 1000000.

4.7.261.  BITEST - Built-In Test Status

      Parameter ID: %x00.01.04
      Unit Usage: Device identifier/0=Whole Aircraft
      SubUnit Usage: Test Number/0=Roll up of all tests for device
      Format: CASMSG (See Table 32.)
      Range: There SHALL NOT be a Range Parameter for this parameter.

5.  Message Transport

5.1.  Message Composition

   Application software on a node determines when information or raw
   data need to be sent onto the network.  These transmissions are done
   as messages with raw data and messages with parameters.  If
   subsequent information or raw data having the same message class, ID,
   and flags occur in a timely fashion, they MAY be coalesced into a
   single message.




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   For each parameter to be sent, the common header (See Section 4.2)
   for the message data items MUST be populated.  In addition, the Ident
   and Parameter Data MUST be populated with the corresponding data as
   per Section 4.7.  The length in the common header MUST represent the
   actual length of the data, however, each parameter must be padded to
   a size that is a multiple of four octets.

   The message header MUST be populated with the corresponding data as
   per Section 4.1, the message number MUST be monotonically increasing
   with an arbitrary initial value, and then the length in the common
   header MUST be set equal to the sum of the padded parameter length
   values.  Once this assembly process is complete, the message can be
   transmitted.

5.2.  Message Transmission and Reliability

   XSEDE is designed to be used with a multicast UDP protocol however,
   there is no requirement to do so.  Each endpoint MUST specify a
   listening address and port number with the default being 224.0.0.69
   on port 20234 for IPv4.  The actual address and port number are to be
   chosen by the system designer / installer for their particular needs.
   [RFC5771] specifies IPv4 Multicast Address Assignments and SHOULD be
   followed.

   If the XSEDE message is successfully transmitted, no further action
   is required.  Data assurance is the responsibility of the nodes
   implementing the XSEDE protocol.

5.3.  Message Reception & decoding

   XSEDE messages are received on the address and port that was
   configured in the prior section.  The structure of the XSEDE message
   is designed to for flexible deployment in different networks.  A node
   MAY use the src id to filter messages.  This can either be a node
   filtering its own sent messages or filtering out messages from
   irrelevant nodes (i.e. selecting only specific computers when playing
   back a QAR file).  The message number allows a node to ensure that
   messages are not processed out of sequence or duplicated.  A node
   SHOULD ignore any message that is received out of sequence.  A node
   MAY use the parameter identifiers to determine what information if
   any is relevant for local processing.  Local processing is beyond the
   scope of this document.

   Since there is no assured message delivery, all parameter
   interpretations MUST be idempotent to ensure multiple
   interpretations, or execution results in the same outcome.





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5.4.  Message Signing

   Since XSEDE operates on a closed network, message signing is not
   currently supported but may be added in the future.

6.  Example Message Flows

   This section illustrates XSEDE features by example.  The first
   example controls the radio.

6.1.  Adjust radio

   This example sets the radio Set Radio frequency and squelch by
   broadcasting USERSEL parameters.  If a node controlling the radio
   receives the request, it will respond with a result similar to the
   one shown afterwards.

6.1.1.  Message Header

                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    src id                     |    message number             |
      |         1001                  |          20                   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   msg class   | message ID    |       flags                   |
      |   3 = OP      | FLIGHTDATA 2  |    LEVEL-A    5               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              tcid             |          len                  |
      |       NONE    0               |          %x10                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
         ...

                      Figure 4: Message Header Format

   src id:
      UINT16; This value was set to 1001 decimal at installation time.

   message number:
      UINT16; 20 decimal for illustration purposes.

   msg class:
      UINT8; "OP" value 3 decimal.

   message ID:
      UINT8; FLIGHTDATA decimal 2





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   flags:
      UINT16; LEVEL-A decimal 5; See Table 21.

   tcid:
      t-NONE; See Table 22.

   len:
      UINT16 ; 0x10, or decimal 16 octets.

6.1.2.  Frequency Message Header

                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      |               2               |             0                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len   |              Ident                    |
      |          4            |  COMFREQKHZ %x00.00.24                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      |  UINT   2     | USERSEL 192   |    %x00    | LEVEL-A    5     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      :                  Parameter   Data                             :
      |                122750   or  0x0001 df7e                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                   Figure 5: Setting frequency to 122.750

   Unit:
      UINT16; decimal 2 to match the requested radio.

   SubUnit:
      UINT16; 0 to signify the radio itself.

   Parameter Data Len:
      11 bits; decimal 4.

   Ident:
      21 bits; COMFREQKHZ - Communication Frequency, value %x00.00.24
      See Section 4.7.

   Format:
      UINT (OCTET): decimal 2.  See Section 4.3.

   Confidence:
      decimal 192 (OCTET): USERSEL.  See Table 23.




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   Expire:
      OCTET; Time to live. %x00 to not expire.  See Section 4.2.2 for
      encoding.

   Pflags:
      LEVEL-A (OCTET) decimal 5.  See Table 21

   Parameter Data:
      *(OCTET) value would be 122750, 0x0001 df7e.

6.1.3.  Squelch Message Header

                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      |               2               |             0                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len   |              Ident                    |
      |          4            |  COMSQL %x00.00.28                    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      |  UINT   2     | USERSEL 192   |    %x00    | LEVEL-A    5     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      :                  Parameter   Data                             :
      |                   53  or  0x0000 0035                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                      Figure 6: Setting Squelch to 53

   Unit:
      UINT16; decimal 2 to match the requested radio.

   SubUnit:
      UINT16; 0 to signify the radio itself.

   Parameter Data Len:
      11 bits; decimal 4.

   Ident:
      21 bits; COMSQL - Communication Squelch (0-100), value %x00.00.28
      See Section 4.7.

   Format:
      UINT (OCTET): decimal 2.  See Section 4.3.

   Confidence:
      decimal 192 (OCTET): USERSEL.  See Table 23.



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   Expire:
      OCTET; Time to live. %x00 to not expire.  See Section 4.2.2 for
      encoding.

   Pflags:
      LEVEL-A (OCTET) decimal 5.  See Table 21

   Parameter Data:
      *(OCTET) value would be 53, 0x0000 0035.

6.1.4.  Radio Status Report

   After the above parameters affect a change in the radio, or as part
   of the radio's regularly scheduled parameter broadcast, a message
   like the following will be transmitted.  It has almost all the same
   values as the original message but would likely include other
   parameters as well.  Only the changed parameters are described.

   The expire time is chosen at 2-3 times the scheduled broadcast time
   to ensure a fresh message is received within the valid time period
   should one be lost.






























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                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |           src id              |      message number           |
      |            1777               |          1255                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   msg class   | message ID    |       flags                   |
      |   3 = OP      | FLIGHTDATA 2  |    LEVEL-A    5               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              tcid             |          len                  |
      |       NONE    0               |          %x20                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      |               2               |             0                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len   |              Ident                    |
      |          4            |  COMFREQKHZ %x00.00.24                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      |  UINT   2     | RAW / R 10    |    %xC9    | LEVEL-A    5     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      :                  Parameter   Data                             :
      |                122750   or  0x0001 df7e                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      |               2               |             0                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len   |              Ident                    |
      |          4            |  COMSQL %x00.00.28                    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      |  UINT   2     |  RAW / R 10   |    %xC9    | LEVEL-A    5     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      :                  Parameter   Data                             :
      |                   53  or  0x0000 0035                         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                      Figure 7: Radio Response Message

   src id:
      UINT16; This value is different than the prior message because
      this message is sent by the node controlling the radio.  It was
      set to 1777 decimal at installation time.

   message number:
      UINT16; decimal 1255 for illustrative purposes.  Note: this value
      is the current message sequence number for node 1777.




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   Confidence:
      decimal 10 (OCTET): RAW / REPORTED in both parameters since this
      value is the actual reported value from the device.  See Table 23.

   Expire:
      OCTET; Time to live. %xC9 to expire in about 15 seconds.  See
      Section 4.2.2 for encoding.

6.2.  Deploy Landing Gear Example

   Landing Gear changes are different than radio changes in that it may
   take several seconds to affect a change.  In this scenario, we will
   see a report by the node controlling the landing gear, followed by a
   parameter showing the user selecting a new value.  Next, there will
   be a series of parameter broadcasts that showing the gear moving into
   position.

6.2.1.  Initial Gear State Message

































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                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |           src id              |      message number           |
      |            2222               |          3400                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   msg class   | message ID    |       flags                   |
      |   3 = OP      | FLIGHTDATA 2  |    LEVEL-A    5               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              tcid             |          len                  |
      |       NONE    0               |          %x20                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      |               1               |             0                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len   |              Ident                    |
      |          4            |        LDGGEAR %x00.00.b2             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      |  UINT   2     | RAW / R 10    |    %x77    | LEVEL-A    5     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      :                  Parameter   Data                             :
      |                    0x8000   -   up.                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      |               2               |             0                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len   |              Ident                    |
      |          4            |  LDGGEAR %x00.00.b2                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      |  UINT   2     | RAW / R 10    |    %x77    | LEVEL-A    5     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      :                  Parameter   Data                             :
      |                    0x8000   -   up.                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 8: Initial gear state message

   Above we see a periodic message indicating that each of the two
   landing gear are in an up position.  If these were the only two
   landing gear, an alternative representation would be to send a single
   parameter with a a unit of zero to indicate all gear is in an up
   position.  The attributes of the message are as follows:

   src id:
      UINT16; This value was set to 2222 decimal at installation time.




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   message number:
      UINT16; 3400 decimal for illustration purposes.

   msg class:
      UINT8; "OP" value 3 decimal.

   message ID:
      UINT8; FLIGHTDATA decimal 2

   flags:
      UINT16; LEVEL-A decimal 5; See Table 21.

   tcid:
      t-NONE; See Table 22.

   len:
      UINT16 ; 0x20 octets.

   Parameter (First):
      Unit:
         UINT16; Decimal 1 for landing gear unit 1

      SubUnit:
         UINT16; 0

      Parameter Data Len:
         11 bits; decimal 4.

      Ident:
         21 bits; LDGGEAR - Landing Gear State, value %x00.00.b2 See
         Section 4.7.

      Format:
         UINT (OCTET): decimal 2.  See Section 4.3.

      Confidence:
         decimal 10 (OCTET): RAW.  It is the value reported by the
         actuator.  See Table 23.

      Expire:
         OCTET; Time to live. %x77 to expire in 2.9 seconds.  See
         Section 4.2.2 for encoding.

      Pflags:
         LEVEL-A (OCTET) decimal 5.  See Table 21

      Parameter Data:
         *(OCTET) value is 0x8000.



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   Parameter (Second):
      Unit:
         UINT16; Decimal 2 for landing gear unit 2

      SubUnit:
         UINT16; 0

      Parameter Data Len:
         11 bits; decimal 4.

      Ident:
         21 bits; LDGGEAR - Landing Gear State, value %x00.00.b2 See
         Section 4.7.

      Format:
         UINT (OCTET): decimal 2.  See Section 4.3.

      Confidence:
         decimal 10 (OCTET): RAW.  It is the value reported by the
         actuator.  See Table 23.

      Expire:
         OCTET; Time to live. %x77 to expire in 2.9 seconds.  See
         Section 4.2.2 for encoding.

      Pflags:
         LEVEL-A (OCTET) decimal 5.  See Table 21

      Parameter Data:
         *(OCTET) value is 0x8000.

6.2.2.  Gear Position Request



















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                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |           src id              |      message number           |
      |            1001               |          2001                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   msg class   | message ID    |       flags                   |
      |   3 = OP      | FLIGHTDATA 2  |    LEVEL-A    5               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              tcid             |          len                  |
      |       NONE    0               |          %x10                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      |               0               |             0                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len   |              Ident                    |
      |          4            |        LDGGEARREQ  %x00.00.b3         |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      |  UINT   2     | RAW / R 10    |    %x00    | LEVEL-A    5     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      :                  Parameter   Data                             :
      |                       0x0001, down.                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 9: Request Gear Position Down

   Below we see an example message that could have been made by a
   landing gear button.

   src id:
      UINT16; This value was set to 1001 decimal at installation time.

   message number:
      UINT16; 2001 decimal for illustration purposes.

   msg class:
      UINT8; "OP" value 3 decimal.

   message ID:
      UINT8; FLIGHTDATA decimal 2

   flags:
      UINT16; LEVEL-A decimal 5; See Table 21.

   tcid:
      t-NONE; See Table 22.




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   len:
      UINT16 ; 0x10 or 16 decimal octets.

   Parameter (Only):
      Unit:
         UINT16; Decimal 0 for the plane's landing gear.

      SubUnit:
         UINT16; 0

      Parameter Data Len:
         11 bits; decimal 4.

      Ident:
         21 bits; LDGGEARREQ - Landing Gear State Request, value
         %x00.00.b3 See Section 4.7.

      Format:
         UINT (OCTET): decimal 2.  See Section 4.3.

      Confidence:
         decimal 192 (OCTET): USERSEL.  See Table 23.

      Expire:
         OCTET; Time to live. %x00 to not expire.  See Section 4.2.2 for
         encoding.

      Pflags:
         LEVEL-A (OCTET) decimal 5.  See Table 21

      Parameter Data:
         *(OCTET) 0x0001, down.

6.2.3.  First Changed Gear State Message

















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                         1                   2                   3
     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |           src id              |      message number           |
    |            2222               |          3401                 |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |   msg class   | message ID    |       flags                   |
    |   3 = OP      | FLIGHTDATA 2  |    LEVEL-A    5               |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |              tcid             |            len                |
    |       NONE    0               |           %x20                |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |             Unit              |           SubUnit             |
    |               1               |             0                 |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |  Parameter Data Len   |              Ident                    |
    |          4            |  LDGGEAR %x00.00.b2                |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |     Format    |  Confidence   |   Expire   |      Pflags      |
    |  UINT   2     | RAW / R 10    |    %x77    | LEVEL-A    5     |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    :                  Parameter   Data                             :
    |                     0x3901, in transit                           |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |             Unit              |           SubUnit             |
    |               2               |             0                 |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |  Parameter Data Len   |              Ident                    |
    |          4            |  LDGGEAR %x00.00.b2                |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |     Format    |  Confidence   |   Expire   |      Pflags      |
    |  UINT   2     | RAW / R 10    |    %x77    | LEVEL-A    5     |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    :                  Parameter   Data                             :
    |                   0x4121, in transit                          |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

              Figure 10: First Changed Gear State Message

   The above message was sent while the landing gear was in transit.  It
   shows the position values for each gear to be different, but both in
   transit.  The expiry is set to 0x77 and about 2.9 seconds as the
   sending node intends to send updates at least once per second.  The
   longer time period accounting for potential losses.

   src id:
      UINT16; This value was set to 2222 decimal at installation time.




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   message number:
      UINT16; 3401 decimal for illustration purposes.

   msg class:
      UINT8; "OP" value 3 decimal.

   message ID:
      UINT8; FLIGHTDATA decimal 2

   flags:
      UINT16; LEVEL-A decimal 5; See Table 21.

   tcid:
      t-NONE; See Table 22.

   len:
      UINT16 ; 0x20 octets.

   Parameter (First):
      Unit:
         UINT16; Decimal 1 for landing gear unit 1

      SubUnit:
         UINT16; 0

      Parameter Data Len:
         11 bits; decimal 4.

      Ident:
         21 bits; LDGGEAR - Landing Gear State, value %x00.00.b2 See
         Section 4.7.

      Format:
         UINT (OCTET): decimal 2.  See Section 4.3.

      Confidence:
         decimal 10 (OCTET): RAW.  It is the value reported by the
         actuator.  See Table 23.

      Expire:
         OCTET; Time to live. %x77 to expire in 2.9 seconds.  See
         Section 4.2.2 for encoding.

      Pflags:
         LEVEL-A (OCTET) decimal 5.  See Table 21

      Parameter Data:
         *(OCTET) value is 0x3901, in transit .



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   Parameter (Second):
      Unit:
         UINT16; Decimal 2 for landing gear unit 2

      SubUnit:
         UINT16; 0

      Parameter Data Len:
         11 bits; decimal 4.

      Ident:
         21 bits; LDGGEAR - Landing Gear State, value %x00.00.b2 See
         Section 4.7.

      Format:
         UINT (OCTET): decimal 2.  See Section 4.3.

      Confidence:
         decimal 10 (OCTET): RAW.  It is the value reported by the
         actuator.  See Table 23.

      Expire:
         OCTET; Time to live. %x77 to expire in 2.9 seconds.  See
         Section 4.2.2 for encoding.

      Pflags:
         LEVEL-A (OCTET) decimal 5.  See Table 21

      Parameter Data:
         *(OCTET) value is 0x4121, in transit.

6.2.4.  Final Gear State Message



















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                           1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |           src id              |      message number           |
      |            2222               |          3402                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   msg class   | message ID    |       flags                   |
      |   3 = OP      | FLIGHTDATA 2  |    LEVEL-A    5               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |              tcid             |            len                |
      |       NONE    0               |            %x20               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      |               1               |             0                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len   |              Ident                    |
      |          4            |  LDGGEAR %x00.00.b2                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      |  UINT   2     | RAW / R 10    |    %xDB    | LEVEL-A    5     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      :                  Parameter   Data                             :
      |                     0x0001, down.                             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             Unit              |           SubUnit             |
      |               2               |             0                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Parameter Data Len   |              Ident                    |
      |          4            |  LDGGEAR %x00.00.b2                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Format    |  Confidence   |   Expire   |      Pflags      |
      |  UINT   2     | RAW / R 10    |    %xDB    | LEVEL-A    5     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      :                  Parameter   Data                             :
      |                     0x0001, down.                             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 11: Final Gear State Message

   The mesage above indicates that both landing gear are down (value
   0x0001) and the message expiry has increased to 0xDB, or about 59
   seconds.  Since the gear are now in a static position, the node only
   intends to send updates every 20 seconds or so following the expire a
   message at about three times the sending frequency.  In practice, to
   ensure delivery the long expiry should be introduced after at least
   one prior notification that it reached that state.





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   src id:
      UINT16; This value was set to 2222 decimal at installation time.

   message number:
      UINT16; 3402 decimal for illustration purposes.

   msg class:
      UINT8; "OP" value 3 decimal.

   message ID:
      UINT8; FLIGHTDATA decimal 2

   flags:
      UINT16; LEVEL-A decimal 5; See Table 21.

   tcid:
      t-NONE; See Table 22.

   len:
      UINT16 ; 0x20 octets.

   Parameter (First):
      Unit:
         UINT16; Decimal 1 for landing gear unit 1

      SubUnit:
         UINT16; 0

      Parameter Data Len:
         11 bits; decimal 4.

      Ident:
         21 bits; LDGGEAR - Landing Gear State, value %x00.00.b2 See
         Section 4.7.

      Format:
         UINT (OCTET): decimal 2.  See Section 4.3.

      Confidence:
         decimal 10 (OCTET): RAW.  It is the value reported by the
         actuator.  See Table 23.

      Expire:
         OCTET; Time to live. %x77 to expire in 2.9 seconds.  See
         Section 4.2.2 for encoding.

      Pflags:
         LEVEL-A (OCTET) decimal 5.  See Table 21



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      Parameter Data:
         *(OCTET) value is 0x0001, down.

   Parameter (Second):
      Unit:
         UINT16; Decimal 2 for landing gear unit 2

      SubUnit:
         UINT16; 0

      Parameter Data Len:
         11 bits; decimal 4.

      Ident:
         21 bits; LDGGEAR - Landing Gear State, value %x00.00.b2 See
         Section 4.7.

      Format:
         UINT (OCTET): decimal 2.  See Section 4.3.

      Confidence:
         decimal 10 (OCTET): RAW.  It is the value reported by the
         actuator.  See Table 23.

      Expire:
         OCTET; Time to live. %x77 to expire in 2.9 seconds.  See
         Section 4.2.2 for encoding.

      Pflags:
         LEVEL-A (OCTET) decimal 5.  See Table 21

      Parameter Data:
         *(OCTET) value is 0x0001, down.

7.  IANA Considerations

   This memo includes no request to IANA.

8.  Security Considerations

   This document should not affect the security of the Internet.

   This protocol is currently designed to be deployed on an isolated
   private network.  As such, message encryption, authenticity, and
   modification detection are not protocol priorities.






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8.1.  Interception

   Message Interception is not considered a significant threat for XSEDE
   because there is no private data in the system.

8.2.  Impersonation and MITM

   Impersonation and Man in the Middle (MITM) are unlikely because
   normally the network is physically isolated and not routed to other
   networks.  Strategies for signing messages are a future
   consideration.

8.3.  Denial of Service

   Due to secure installation and physical isolation, Denial of Service
   is not a significant concern.

9.  References

9.1.  Normative References

   [RFC0768]  Postel, J., "User Datagram Protocol", STD 6, RFC 768,
              DOI 10.17487/RFC0768, August 1980,
              <https://www.rfc-editor.org/info/rfc768>.

   [RFC0791]  Postel, J., "Internet Protocol", STD 5, RFC 791,
              DOI 10.17487/RFC0791, September 1981,
              <https://www.rfc-editor.org/info/rfc791>.

   [RFC2640]  Curtin, B., "Internationalization of the File Transfer
              Protocol", RFC 2640, DOI 10.17487/RFC2640, July 1999,
              <https://www.rfc-editor.org/info/rfc2640>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [IEEE8023] IEEE, "IEEE Standard for Ethernet",
              DOI 10.1109/ieeestd.2018.8457469, 21 September 2018,
              <https://doi.org/10.1109/ieeestd.2018.8457469>.

   [DO-178C]  RTCA - Radio Technical Commission for Aeronautics, "DO-
              178C - Software Considerations in Airborne Systems and
              Equipment Certification", December 2011,
              <https://my.rtca.org/
              productdetails?id=a1B36000001IcmrEAC>.





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   [GDL90]    Garmin International, Inc., "GDL 90 Data Interface
              Specification", June 2007, <https://www.faa.gov/sites/faa.
              gov/files/air_traffic/technology/adsb/archival/
              GDL90_Public_ICD_RevA.PDF>.

9.2.  Informative References

   [RFC5771]  Cotton, M., Vegoda, L., and D. Meyer, "IANA Guidelines for
              IPv4 Multicast Address Assignments", BCP 51, RFC 5771,
              DOI 10.17487/RFC5771, March 2010,
              <https://www.rfc-editor.org/info/rfc5771>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

Authors' Addresses

   Mark Spencer
   Avilution
   115 Houston Goodson Way SW
   Huntsville, AL 35824
   United States of America
   Email: markster@avilution.com


   Edward T Guy, III (editor)
   Bloomberg
   New York, NY
   United States of America
   Email: edguy@eguy.org


   Nick Hartley
   Avilution
   115 Houston Goodson Way SW
   Huntsville, AL 35824
   United States of America
   Email: nick@avilution.com











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