Garmin GNC 255 User Manual

GTR 225/GNC 255 TSO Installation Manual 190-01182-02
Page B-4 Rev. B
Table B-2 describes the Type 2 aviation output sentence item designator (id), sequence number (seq),
waypoint identifier (wpt), waypoint latitude (lat), waypoint longitude (lon), and magnetic variation at
waypoint (mvar) fields.
Table B-2. Type 2 Aviation Output Sentence Format
Field Byte
Format
7 6 5 4 3 2 1 0
Description
id
1
2-3
ASCII character 'w' (77 hex)
Two ASCII numeric characters representing route
sequence number of waypoint (01 to 31)
seq
1
x l a n n n n n
x - undefined
l - 1 if last waypoint in route
a - 1 if active to waypoint
nnnnn - route sequence number of waypoint
(unsigned binary)
wpt
1-5
Destination waypoint identifier (will be blank filled on
right if less than 5 characters in identifier)
lat
1
2
3
s d d d d d d d
x x m m m m m m
x h h h h h h h
s - 0 (north) or 1 (south)
ddddddd - latitude degrees (unsigned binary)
xx - undefined
mmmmmm- latitude minutes (unsigned binary)
x - undefined
hhhhhhh - hundredths of latitude minutes
(unsigned binary)
lon
1
2
3
4
s x x x x x x x
d d d d d d d d
x x m m m m m m
x h h h h h h h
s - 0 (east) or 1 (west)
xxxxxxx - undefined
dddddddd - longitude degrees (unsigned binary)
xx - undefined
mmmmmm- latitude minutes (unsigned binary)
x - undefined
hhhhhhh - hundredths of latitude minutes
(unsigned binary)
mvar
1-2
Two's complement binary in 16ths of degrees.
Easterly variation is positive. MSB output
first.

Garmin GNC 255 Specifications

General

Channels	760
Frequency Range	118.000 to 136.975 MHz
Channel Spacing	25 kHz
Input Voltage	11 to 33 VDC
Dimensions	159 x 50 x 193 mm