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GBX Reference Manual 53
4.8 GPS Receiver NMEA Data Messages
In this section, GGA, GLL, GSA, GSV, RMC, SAT, VTG, and ZDA NMEA
data messages are defined.
Note - By default the GBX is configured to output the GGA, GSA,
GSV (or SAT for GBX-PRO), VTG, and ZDA (RMC for GBX-12R)
messages.
4.8.1 GGA Data Message
The GGA message contains detailed GPS position information, and is
the most frequently used NMEA data message. In Table 4-2, the GGA
data message is broken down into its components. This message
takes the following form:
$GPGGA,hhmmss.ss,ddmm.mmmmm,s,dddmm.mmmmm,s,n,qq,pp.p,
saaaaa.aa,M,
±
xxxx.xx,M,sss,aaaa*cc<CR><LF>
Table 4-2 GGA Data Message Defined
Field Description
hhmmss.ss UTC time in hours, minutes, seconds of the GPS position
ddmm.mmmmm Latitude in degrees, minutes, and decimal minutes
s s = N or s = S, for North or South latitude
dddmm.mmmmm Longitude in degrees, minutes, and decimal minutes
s s =E or s = W, for East or West longitude
n Quality indicator, 0 = no position, 1 = undifferentially corrected position, 2
= differentially corrected position, 9= position computed using almanac
qq Number of satellites used in position computation
pp.p HDOP =0.0 to 9.9
saaaa.aa Antenna altitude
M Altitude units, M = meters
±
xxxx.xx Geoidal separation (needs geoidal height option)
M Geoidal separation units, M = meters
sss Age of differential corrections in seconds
aaa Reference station identification
*cc Checksum