Garmin 010-00859-00 Installation Manual - page 38
Page B-2
GDL 88 TSO Installation Manual
Rev. A
190-01122-00
Appendix B GDL 88 DATA FORMAT
B.1 GDL 88 RS-232 Fuel/Air Data Input Format
B.1.1 Electrical Interface
The input signals are compatible with RS-232C. Data input at 9600 baud (1200 baud for Apollo Altitude
Encoder) with a word length of 8 bits, one stop bit, and no parity. One message is received per second.
B.1.2 Icarus Altitude Sentence
The GDL 88 is capable of receiving the following 10-byte message from the Icarus Altitude Serializer:
ALT
Where:
ALT
ASCII characters
space (0x20)
12345
altitude in feet
carriage return (0x0d)
B.1.3 Apollo Altitude Sentence
The GDL 88 is capable of receiving the following 17-byte message from an Apollo Altitude Encoder:
#AL
Where:
#AL
ASCII characters
space (0x20)
<+/->
sign indicator (0x2B[“+”] or 0x2D[“-“])
ddddd
altitude in feet (-1000 feet to 35,000 feet)
T
ASCII characters
<+/->
sign indicator
dd
sensor temperature
ul
checksum of bytes 1 through 14 in hex ASCII (i.e. “FA”)
carriage return (0x0D)