Garmin Apollo CNX80, Installation Manual

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Appendix B - Serial Interface Specifications
B-4 560-0982-00 Rev D Apollo CNX80 Installation Manual
Table B- 3 - Fuel/Air Data Message Data (S Format)
Item
Desig
Message
Format Message
Mnemonic Field
Width
Message Description
= no errors
SR ddddd REM 10 Fuel remaining (0-9999.9 in gallons)
S* ddd CKSUM 7 Checksum of all characters preceding this record. The
checksum is a one byte checksum (discarding carries)
including all characters from the initial STX up to and
including the line feed preceding the checksum message.
B.1.2.2 “Z” Data Format
The format of the fuel/air data computer input is as follows, which conforms to the Shadin “Z” format
serial message. Definition of the input message data that the CNX80 uses is included in Table B- 4.
Baud rate: .............................................9600
Data bits: ..............................................8
Stop bits: ...............................................1
Parity: ...................................................none
Expected input rate: ...............................approx. 1 second
Message length: .....................................variable (512 character max.)
Example Fuel / Airdata Input Data
<STX>SA223
223 knots indicated air speed
SB230
230 knots true air speed
SC101
0.101 mach
SD+3200
32,000 feet pressure altitude
SE+3312
33,120 feet density altitude
SF+05
+5°C outside air temp
SG-03
-3°C true air temp
SH010
wind direction at 10° (relative to true north)
SI015
wind speed at 15 knots
SJ+03
+3° / second right turn
SK-050
-50 feet / second vertical air speed
SL359
359° heading (relative to true north)
SM0123
12.3 gallons / hour - right engine fuel flow
SN0300
30.0 gallons used - right engine
SO0131
13.1 gallons / hour - left engine fuel flow
SP0310
31.0 gallons used - left engine
SQ000
no errors
SR01227
122.7 gallons remaining
S*123
Checksum (example only, not actual)
<ETX>
end of message string
Figure B- 2 - Fuel / Airdata Data Input (S Format)