SIM66 Series_NMEA Message_User Guide_V1.01
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Lon
STR
Longitude, in the format of dddmm.mmmmmm
ddd Degrees
mm.mmmmmm Minutes
E
STR
East longitude or west longitude indicator
E East longitude
W West longitude
spd
DOUBLE
Speed over ground, unit: knot
cog
DOUBLE
Course over ground, unit: degree
Calculated clockwise from north
date
STR
UTC date, in the format of ddmmyy
dd Day
mm Month
yy Year
If the exact year, month, and day are not parsed, the date
part appears blank
mv
DOUBLE
Magnetic declination, specified to null
mvE
STR
Magnetic declination direction, specified to constant E
mode
STR
Positioning mode
N Not positioning
A Point positioning
D Differential positioning
E INS positioning
cs
STR
Checksum
A hexadecimal number obtained by calculating an XOR of
all characters from '$' to '*' in this statement
<CR><LF>
End of message termination
2.4.6 Message ID VTG: Output Track Direction and Ground Speed
Syntax:$VTG,cogt,T,cogm,M,sog,N,kph,K,mode*cs
Example:$GNVTG,0.000,T,,M,0.000,N,0.000,K,A*13
Parameter
Format
Description
--
STR
Positioning system flag
GP GPS+SBAS+QZSS joint positioning(1)
BD BDS system standalone positioning
GN Multiple system joint positioning
cogt
DOUBLE
Course over ground with reference to true north
(0.000~359.999 degrees)
T
STR
Course flag, specified to constant T
cogm
DOUBLE
Course over ground with reference to MN (0.000~359.999
degrees). The field is empty by default
sog
DOUBLE
Speed over ground, unit: knot
N
STR
Unit of speed, specified to constant N