Furuno INMARSAT-C FELCOM 18 Operator's Manual page 163

DTM: Datum reference
$**DTM,ccc,a,x.x,a,x.x,a,x.x,ccc*hh<CR><LF>
1 2 3 4 5 6 7
1. Local datum (W84=WGS84 W72=WGS72 S85=SGS85, P90=PE90
User defined=999, IHO datum code
2. Local datum subdivision code (NULL or one character)
3. Lat offset, min (-59.99999 - 59.59999)
4. N/S
5. Lon offset, min (no use)
6. E/W
7. Altitude offset, meters (no use)
8. Reference datum (W84=WGS84 W72=WGS72 S85=SGS85, P90=PE90)
GGA: Global positioning system fix data
$**GGA,hhmmss.ss,llll.lll,a,yyyyy.yyy,a,x,xx,x.x,x.x,M,x.x,M,x.x,xxxx*hh<CR><LF>
1
1. UTC of position (no use)
2. Latitude (0.00000 - 9000.00000)
3. N/S
4. Longitude (0.00000 - 18000.00000)
5. E/W
6. GPS quality indicator (1 -8)
7. Number of satllite in use (00 -12)
8. Horizontal dilution of precision (0.00 - 999.99), No use
9. Antenna altitude above/below mean sealevel (-999.99 - 9999.99), No use
10. Unit, m, No use
11. Geoidal separation (-999.99 - 9999.99), No use
12. Unit, m, No use
13. Age of differential GPS data (0 - 99), Ver. 2.0, 3.0 only
14. Differential reference station ID (0000-1023), Ver. 2.0, 3.0 only
GLL: Geographic position
$**GLL,llll.lll,a,yyyyy.yyy,a,hhmmss.ss,a,x*hh<CR><LF>
1 2 3
1. Latitude (0.00000 - 9000.00000)
2. N/S
3. Longitude (0.00000 - 18000.00000)
4. E/W
5. UTC of position (no use), Ver 2.0, 3.0 only
6. Status (A=data valid V=data invalid), Ver 2.0, 3.0 only
7. Mode indicator* (A=Autonomous D=Differential E= Estimated M=Manual S=Simulator)
* Ver. 3.0 only)
8
2 3 4 5 6 7 8
4 5 6 7
9 10 11 12 13 14
APPX. 6 DIGITAL INTERFACE
AP-29