Furuno RD-50 Operator's Manual page 77

GGA - Global positioning system (GPS) 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>
--
UTC of position
GLL - Geographic position
$ GLL, llll.lll, a, yyyyy.yyy, a, hhmmss.ss, A, a*hh<CR><LF>
--
Latitude, N/S
Note 1: Positioning system mode indicator:
A=Autonomous, D=Differential, E=Estimated (dead reckoning),
M=Manual input, S=Simulator, N=Data not valid
Note 2: The mode indicator field supplements the status field (field 6). The status field should be set to
V=invalid for all values of operating mode except for A=Autonomous and D=Differential. The
positioning system mode indicator and status fields should not be null fields.
GNS - GNSS fix data
$ GNS, hhmmss.ss, llll.lll, a, yyyyy.yyy, a, c
--
UTC of position
Note: N=No fix, A=Autonomous, D=Differential, P=Precise, R=Real Time Kinematic, F=Float RTK,
E=Estimated Mode, M=Manual Input Mode, S=Simulator Mode
Number of satellites in use, 00-12, may be
different from the number in view
GPS quality indicator
Longitude, E/W
Latitude, N/S
Status (see Note 2), A=data valid, V=data invalid
UTC of Position
Longitude, E/W
c, xx, x.x, x.x, x.x x.x, x.x*hh<CR><LF>
--
Mode indicator (see Note)
Longitude, E/W
Latitude, N/S
APPENDIX 4 DIGITAL INTERFACE
Age of differential
GPS date
Units of geoidal separation, m
Geoidal separation
Units of antenna altitude, m
Antenna altitude above/below mean sea
level (geoid)
Horizontal dilution of precision
Checksum
Mode indicator (see Note 1 and 2)
Differential reference
station ID
Age of differential data
Geoidal separation, m
Antenna altitude, m,
re:mean-sea-level (geoid)
HDOP
Total number of satellites in use, 00-99
Checksum
Differential reference
station ID, 0000-1023
Checksum
AP-7