NMEA GLL datagram format
The NMEA GLL datagram transfers the latitude and longitude of vessel position, the time of the position fix and the current status from a global positioning system (GPS).
Format
$--GLL,llll.ll,a,yyyyy.yy,a,hhmmss.ss,A,a*hh<CR><LF>
Description
1 $—: Talker identifier
2 GLL: Datagram identifier
3 llll.ll,a: Latitude, North/South (Degrees, minutes and hundredths)
•  N = North
•  S = South
4 yyyyy.yy,a: Longitude, East/West (Degrees, minutes and hundredths)
•  E = East
•  W = West
5 hhmmss.ss: Coordinated Universal Time (UTC) of the current position
6 A: Status
•  A = The data are valid.
•  V = The data are not valid.
7 a: Mode indicator
8 *hh: Checksum