and 
NMEA VTG message
Popular NMEA messages
Course over ground and ground speed (VTG)
| Message | NMEA-Standard-VTG Course over ground and ground speed |
| Comment | Velocity is given as course over ground (COG) and speed over ground (SOG). |
| Information | Number of fields: 12 |
| Structure | $xxVTG,cogt,cogtUnit,cogm,cogmUnit,sogn,sognUnit,sogk,sogkUnit,posMode*cs\r\n |
| Example | $GPVTG,77.52,T,,M,0.004,N,0.008,K,A*06\r\n |
Payload
| Field | Name | Format | Unit | Example | Description |
|---|---|---|---|---|---|
| 0 | xxVTG | string | - | $GPVTG | VTG Message ID (xx = current Talker ID) |
| 1 | cogt | numeric | degrees | 77.52 | Course over ground (true) |
| 2 | cogtUnit | character | - | T | Course over ground units: T (degrees true, fixed field) |
| 3 | cogm | numeric | degrees | - | Course over ground (magnetic) |
| 4 | cogmUnit | character | - | M | Course over ground units: M (degrees magnetic, fixed field) |
| 5 | sogn | numeric | knots | 0.004 | Speed over ground |
| 6 | sognUnit | character | - | N | Speed over ground units: N (knots, fixed field) |
| 7 | sogk | numeric | km/h | 0.008 | Speed over ground |
| 8 | sogkUnit | character | - | K | Speed over ground units: K (kilometers per hour, fixed field) |
| 9 | posMode | character | - | A | Mode indicator |
| 10 | cs | hexadecimal | - | *06 | Checksum |
| 11 | CRLF | character | - | - | Carriage return and line feed |
Based on NMEA documentation provided by u-blox.
Learn more about NMEA protocol:
