GPVTG
Track made good and ground speed
|
Platform: |
OEM719, OEM729, OEM7500, OEM7600, OEM7700, OEM7720, PwrPak7, CPT7, CPT7700, SMART7, SMART2 |
This log contains the track made good and speed relative to the ground.
The GPVTG log outputs these messages without waiting for a valid almanac. Instead, it uses a UTC time, calculated with default parameters. In this case, the UTC time status (see the TIME log) is set to WARNING since it may not be one hundred percent accurate. When a valid almanac is available, the receiver uses the real parameters. Then the UTC time status is set to VALID.
Message ID: 226
Log Type: Synch
Recommended Input:
log gpvtg ontime 1
Example 1 (GPS only):
$GPVTG,224.592,T,224.592,M,0.003,N,0.005,K,D*20
Example 2 (Multi-constellation):
$GNVTG,139.969,T,139.969,M,0.007,N,0.013,K,D*3D
If the NMEATALKER command is set to AUTO, the talker (the first 2 characters after the $ sign in the log header) is set to GP (GPS satellites only), GL (GLONASS satellites only), GA (Galileo satellites only), GQ (for QZSS satellites only), GB/BD (for BeiDou satellites only) or GN (satellites from multiple systems).
See the Note in the GPGGA log that applies to all NMEA logs.
|
Field |
Structure |
Description |
Symbol |
Example |
|
1 |
$GPVTG |
Log header |
|
$GPVTG |
|
2 |
track true |
Track made good, degrees True |
x.x |
24.168 |
|
3 |
T |
True track indicator |
T |
T |
|
4 |
track mag |
Track made good, degrees Magnetic; Track mag = Track true + (MAGVAR correction) See the MAGVAR command |
x.x |
24.168 |
|
5 |
M |
Magnetic track indicator |
M |
M |
|
6 |
speed Kn |
Speed over ground, knots |
x.x |
0.4220347 |
|
7 |
N |
Nautical speed indicator (N = Knots) |
N |
N |
|
8 |
speed Km |
Speed, kilometres/hour |
x.x |
0.781608 |
|
9 |
K |
Speed indicator (K = km/hr) |
K |
K |
|
10 |
mode ind |
Positioning system mode indicator, see Table: NMEA Positioning System Mode Indicator |
a |
A |
|
11 |
*xx |
Check sum |
*hh |
*7A |
|
12 |
[CR][LF] |
Sentence terminator |
|
[CR][LF] |
|
Mode |
Indicator |
|
A |
Autonomous |
|
D |
Differential |
|
E |
Estimated (dead reckoning) mode |
|
M |
Manual input |
|
N |
Data not valid |