Gps Data - Garmin 16-HVS Instruction Manual

3. GPS Data

$GPGGA,hhmmss,llll.lll,a,nnnnn.nnn,b,t,uu,v.v,w.w,M,x.x,M,y.y,zzzz*hh<CR><LF>
The GPS16-HVS has several data formats available. The GPS16-HVS is
configured to output the NEMA $GPGGA time and position string. It is
possible to configure the GPS16-HVS to output other NEMA strings including
the $GPVTG track made good and ground speed string. See Appendix D for
details.
Sample NEMA $GPGGA data string:
TABLE 3-1. NEMA $GPGGA String Definition
Field Description
0 $GPGGA NEMA string identifier
1 hhmmss UTC of Position: Hours, minutes, seconds
2 1111.111 Latitude: Degrees, minutes, thousandths of minutes
3 a N (North) or S (South)
4 nnnnn.nnn Longitude: Degrees, minutes, thousandths of minutes
5 b E (East) or W (West)
6 t GPS Quality Indicator: 0 = No GPS, 1 = GPS, 2 =
DGPS
7 uu Number of Satellites in Use
8 v.v Horizontal Dilution of Precision (HDOP)
9 w.w Antenna Altitude in Meters
10 M M = Meters
11 x.x Geoidal Separation in Meters
12 M M = Meters. Geoidal separation is the difference
between the WGS-84 earth ellipsoid and mean-sea-
level.
13 y.y Age of Differential GPS Data. Time in seconds since
the last Type 1 or 9 Update
14 zzzz Differential Reference Station ID (0000 to 1023)
15 * Asterisk, generally used as the termination character
16 hh Checksum
17 <CR><LF> Carriage return, line feed characters.
Sample $GPGGA output strings:
Cold Start
No satellites acquired, Real Time Clock and Almanac invalid:
$GPGGA,,,,,,0,00,,,,,,,*66
Warm Start
No satellites acquired, time from Real Time Clock, almanac valid:
$GPGGA,235032.0,,,,,0,00,,,,,,,*7D
GPS16-HVS GPS Receiver
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