Garmin GTX 3X5 Series Installation Manual - page 124
190-01499-02
GTX 3X5 Transponder TSO Installation Manual
Rev. 4
Page A-3
SHADIN G FORMAT
GA012
GA (ASCII characters); 012 represents indicated air speed (knots)
GB345
GB (ASCII characters); 345 represents true air speed (knots)
GC678
GC (ASCII characters); 678 represents Mach speed (thousandths)
GD9012
GE3456
GF78
GF (ASCII characters); sign; 78 represents outside air temperature (Celsius)
GG90
GG (ASCII characters); sign; 90 represents true air temperature (Celsius)
GK901
GL234
GL (ASCII characters); 234 represents heading (degrees from north)
GP89012
GP (ASCII characters); 89012 represents fuel used, left (or Single) (tenths
gallons)
GR6789.0
GR (ASCII characters); 6789.0 represents fuel remaining (gallons) [1]
Ga1234
(tens of feet)
Gb56.78
Gb (ASCII characters); 56.78 represents current barometric pressure setting
(inches Hg)
G*901
G* (ASCII characters); 901 represents checksum
Where:
start-transmit character (0x02)
carriage-return character (0x0D)
line-feed character (0x0A)
sign indicator (0x2B[+] or 0x2D[-])
end-transmit character (0x03)
[1] Not available from Airdata Computer
NOTE
Checksum is calculated by adding each byte in the message (including all characters from
discarded to give a one byte result. The ASCII-coded decimal representation of that byte is
given, ranging from 0 (0x30, 0x30, 0x30) to 255 (0x32, 0x35, 0x35).