Trimble Outdoors aggps 332 Benutzerhandbuch

Seite von 126
AgGPS 332 GPS Receiver User Guide     93
NMEA-0183 Messages     C
C.12
VTG (Course Over Ground and Ground Speed)
The VTG (Velocity True Ground) message identifies the actual track 
made good and speed over ground
The VTG message structure is:
$GPVTG,0,T,,,0.00,N,0.00,K*33
Table C.12 describes these fields.
Note – 
Because the contents of this NMEA message do not change 
significantly during a one-second interval, the receiver outputs this 
message at a maximum rate of 1 Hz.
Table C.12
VTG message fields
Field
Description
1
Track made good
2
Fixed text “T” shows that track made good is relative to true north
3
Not used
4
Not used
5
Speed over ground in knots (0–3 decimal places)
6
Fixed text “N” shows that speed over ground is in knots
7
Speed over ground in kilometers/hour (0–3 decimal places)
8
Fixed text “K” shows that speed over ground is in kilometers/hour