User Manual

Speed Over
Ground
0.13
knots
Course Over
Ground
309.62
degrees
True
Date
120598
ddmmyy
Magnetic
Variation
degrees
E=east or W=west
Mode
A
A=Autonomous, D=DGPS, E=DR
Checksum
*10
<CR> <LF>
End of message termination
This sentence reports the actual course and speed relative to the ground.
Table I contains the values for the following example:
$GPVTG,309.62,T, ,M,0.13,N,0.2,K,A*23
Table I: VTG Data Format
Name
Example
Units
Description
Message ID
$GPVTG
VTG protocol header
Course
309.62
Measured heading
Reference
T
True
Course
degrees
Measured heading
Reference
M
Magnetic
Speed
0.13
knots
Measured horizontal speed
Units
N
Knots
Speed
0.2
km/hr
Measured horizontal speed
Units
K
Kilometers per hour
Mode
A
A=Autonomous, D=DGPS, E=DR
Checksum
*23
<CR> <LF>
End of message termination
After a proper power on, the device is ready to receive AT commands on the MODEM serial
port.
The GPS receiver also will be automatically powered on and it will start the scan of the
available GPS signals.
On the NMEA USB port (default 115200 bps, 8, n, 1) there must be presence of the NMEA
sentences.