NMEA GGA datagram format
The NMEA GGA datagram transfers time-, position- and fix-related data from a global positioning system (GPS).
Format
$--GGA,hhmmss.ss,llll.ll,a,yyyyy.yy,a,x,zz,d.d,a.a,M,g.g,M,r.r,cccc*hh
Description
1 $—: Talker identifier
2 GGA: Datagram identifier
3 hhmmss.ss: Coordinated Universal Time (UTC) of the current position
4 llll.ll,a: Latitude, North/South (Degrees, minutes and hundredths)
•  N = North
•  S = South
5 yyyyy.yy,a: Longitude, East/West (Degrees, minutes and hundredths)
•  E = East
•  W = West
6 x: Quality indicator for the GPS (Global Positioning System) (Refer to the NMEA standard for further information about the GPS quality indicator.)
7 zz: Number of satellites in use: (00 - 12) (The number of satellites may be different from the number in view.)
8 d.d: HDOP (Horizontal dilution of precision)
9 a.a,M: Altitude related to mean sea level (geoid) (Metres)
10 g.g,M: Geoidal separation (Metres)
11 r.r: Age of GPS (Global Positioning System) data
12 cccc: Identification of differential reference station: (0000 - 1023)
13 *hh: Checksum