Trimble Outdoors AgGPS 332 - Manual (Page 103)

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