GPS16X-HVS GPS Receiver
10
7.1 $GPGGA Sentence (Position and Time)
Sample NMEA $GPGGA data string:
$GPGGA,hhmmss,llll.lll,a,nnnnn.nnn,b,t,uu,v.v,w.w,M,x.x,M,y.y,zzzz*hh<CR><LF>
TABLE 7-1. NMEA $GPGGA String Definition
Field Description
0
$GPGGA
NMEA 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
Warm Start
One satellite in use, time from GPS Real Time Clock (not GPS), no position:
$GPGGA,183806.0,,,,,0,01,,,,,,,*7D
