APPENDIX
AP-18
VDR – Set and drift
$--VDR,x.x,T,x.x,M,x.x,N*hh<CR><LF>
| | | | | | |
| | | | | | +--------- 4
| | | | +--+----------- 3
| | +--+----------------- 2
+--+----------------------- 1
1. Direction, degrees true
2. Direction, degrees magnetic
3. Current speed, knots
4. Checksum
VHW – Water speed and heading
$--VHW,x.x,T,x.x,M,x.x,N,x.x,K*hh<CR><LF>
| | | | | | | | |
| | | | | | | | +--------- 5
| | | | | | +--+----------- 4
| | | | +--+----------------- 3
| | +---+----------------------- 2
+---+----------------------------- 1
1. Heading, degrees true
2. Heading, degrees magnetic
3. Speed, knots
4. Speed, km/h
5. Checksum
VTG - Course over ground and ground speed
$--VTG,x.x,T,x.x,M,x.x,N,x.x,K,a*hh<CR><LF>
| | | | | | | | | |
| | | | | | | | | +------- 6
| | | | | | | | +--------- 5
| | | | | | +--+----------- 4
| | | | +--+----------------- 3
| | +--+----------------------- 2
+--+----------------------------- 1
1. Course over ground, degrees true
2. Course over ground, degrees magnetic
3. Speed over ground, knots
4. Speed over ground, km/h
5. Mode indicator(see note)
6. Checksum
NOTE Positioning system Mode indicator:
A = Autonomous
D = Differential
S = Simulator
N = Data not valid
The positioning system Mode indicator field shall not be a null field.