Name
ASCII String
Units
Description
Format
Example
M
blank
M
Units
m
DiffAge
numeric
second
Age of
Differential
Corrections
Blank (Null)
fields when
DGPS is not
used
DiffStation
numeric
0
Diff. Reference
Station ID
Cs
hexadecimal
*5B*18
Checksum
<CR> <LF>
End of message
$GPVTG,cogt,T,cogm,M,sog,N,kph,K*cs<CR><LF>
Name
ASCII String
Units
Description
Format
Example
$GPVTG
string
$GPTVTG
Message ID
VTG protocol
header
cogt
numeric
77.52
Degrees
Course over
ground (true)
T
character
T
fixed field
True
cogm
Blank
Course over
ground
(magnetic)
Not output
(empty)
M
character
M
fixed field
Magnetic
sog
numeric
0.004
Knots
Speed over
ground
N
character
N
kph
numeric
0.008
km/h
Speed
K
character
K
K
Kilometers per
https://en.racelogic.support//Product_Info/Sensors/Single_and_Dual_Antenna_Speed_Sensors/VBOX_Speed_Sensor_User_Guide/
07_-_VBOX_Speed_Sensor_RS232%2F%2FNMEA_Output
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