Garmin GNC 255, Installation Manual, Page: 84 / 138

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.