Appendix Bgtn Data Format; Aviation Data Format; Electrical Interface; General Output Format - Garmin GTN 625 Installation Manual

APPENDIX B GTN DATA FORMAT
B.1 RS-232 Aviation Data Format
B.1.1 Electrical Interface
The output signals are compatible with RS-232C. Data is generated at 9600 baud with a word length of 8
bits, one stop bit, and no parity.
B.1.2 General Output Format
The GTN RS-232 data has the following general format:
STX - ASCII start-of-text character (02 hex)
t1s - Type 1 output sentences (see following paragraphs for description)
t2s - One or more type 2 output sentences (see following paragraphs for description)
ETX - ASCII end-of-text character (03 hex)
B.1.3 Aviation Output Sentence Type 1
The Type 1 output sentences have the following general format:
id - item designator (single ASCII alphabetic character)
dddd - item data (1 to 10 printable ASCII characters)
CR - ASCII carriage return character (0D hex)
LF - ASCII line feed character (0A hex)*
Each Type 1 sentence is output by the GTN approximately once every second.
The track, desired track, and bearing to waypoint angles, and the magnetic variation are output according
to the current mode of the GTN (automatic magnetic heading, magnetic variation computed at last known
position; true heading, magnetic variation of E00.0°; or user-defined magnetic heading, magnetic variation
as entered by user).
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Rev. F
GTN 625/635/650 TSO Installation Manual
Page B-1