Trimble Outdoors SK8 - Manual (Page 184)

E-4 Lassen-SK8 Embedded GPS Module
NMEA 0183
E.4.2 GLL - Geographic Position - Latitude/Longitude
The GLL message contains the latitude and longitude of the present vessel position, the
time of the position fix and the status.
GLL,llll.lll,a,yyyyy.yyy,a,hhmmss.s,A
E.4.3 GSA - GPS DOP and Active Satellites
The GSA messages indicates the GPS receiver's operating mode and lists the satellites
used for navigation and the DOP values of the position solution.
GSA,a,x,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,x.x,x.x,x.x
Table E-4. GLL - Geographic Position - Latitude / Longitude Message
Parameters
Field # Description
1,2 Latitude, N (North) or S (South)
3,4 Longitude, E (East) or W (West)
5 UTC of Position
6 Status: A = Valid, V= Invalid
Table E-5. GSA - GPS DOP and Active Satellites Message Parameters
Field # Description
1 Mode: M = Manual, A = Automatic. In manual mode, the receiver is forced
to operate in either 2D or 3D mode. In automatic mode, the receiver is
allowed to switch between 2D and 3D modes subject to the PDOP and
satellite masks.
2 Current Mode: 1 = Fix Not Available, 2 = 2D, 3 = 3D
3 to 14 PRN numbers of the satellites used in the position solution. When less than
12 satellites are used, the unused fields are null
15 Position Dilution of Precision (PDOP)
16 Horizontal Dilution of Precision (HDOP)
17 Vertical Dilution of Precision (VDOP)