NMEA GGK datagram format
The NMEA GGK datagram is used to decode the PTNL, Time, Position, Type and DOP (Dilution of Precision) string of the NMEA 0183 output.
Format
$--GGK,hhmmss.ss,ddmmyy,nnnnn.nnnnnnnn,a,yyyyy.yyyyyyyy,a,x,zz,w.w,EHTeeeeee,u*hh<CR><LF>
Description
1 $—: Talker identifier
2 GGK: Datagram identifier
3 hhmmss.ss: Coordinated Universal Time (UTC) of the current position
4 ddmmyy: Day, month and year
5 nnnnn.nnnnnnnn,a: Latitude, North/South (Degrees, minutes and hundredths)
•  N = North
•  S = South
6 yyyyy.yyyyyyyy,a: Longitude, East/West (Degrees, minutes and hundredths)
•  E = East
•  W = West
7 x: Quality indicator for the GPS (Global Positioning System) (Refer to the NMEA standard for further information about the GPS quality indicator.)
8 zz: Number of satellites in use (00 - 12) (The number of satellites may be different from the number in view.)
9 w.w: PDOP (Position dilution of precision)
10 EHTeeeeee: Ellipsoidal height of fix
11 u: Unit of height measurement
12 *hh: Checksum