Furuno FR-1500 - Manual (Page 105)

-8.5-
GGA - Global positioning system (GPS) fix data
Time, position and fix related data for a GPS receiver.
Differential reference station ID, 0000-1023 *
Age of differential GPS data (see note 2) *
Units of geoidal separation, m *
Geoidal separation (see note 3) *
Units of antenna altitude, m *
Antenna altitude above/below
mean sea level (geoid) *
Horizontal dilution of precision *
Checksum
$--GGA, hhmmss.ss. 1111.11, a, yyyyy.yy, a, x, xx, x.x, x.x, M, x.x, M, x.x, xxxx*hh<CR><LF>
Number of satellites in use, 11-12, may be
different from the number in view *
GPS quality indicator (note 1)
Longitude - E/W
Latitude - N/S
UTC of position *
* Not used
NOTES
1 GPS quality indicator:
0 = fix not available or invalid 6 = Estimated (dead reckoning) mode
1 = GPS SPS mode, fix valid 7 = Manual input mode
2 = differential GPS, SPS mode, fix valid 8 = Simulator mode
3 = GPS PPS mode GPS fix valid
4 = Real Time Kinematic. Satellite system used in RTK mode with fixed integers
5 = Float RTK. Satellite system used in RTK mode with fixed floating integers
2 Time in seconds since last SC104 type 1 or 9 update, null field when DGPS is not used.
3 Geoidal separation: the difference between the WGS-84 earth ellipsoid and mean sea level (geoid), “-“ = mean sea
level below ellipsoid.
GLL - Geographic position - latitude/longitude
$--GLL, llll.ll, a yyyyy.yy, a, hhmmss.ss, A, a *hh<CR><LF>
Checksum
Mode indicator (see note 1 and note 2)
Status (see note 2) A = data valid V = data invalid
UTC of position*
Latitude, N/S
Longitude, E/W
*: Not used
NOTE 1: Positioning system Mode indicator:
A= Autonomous mode
D= Differential mode
E= Estimated (dead reckoning) mode
M= Manual input mode
S= Simulator mode
N= Data not valid
NOTE 2: The Mode Indicator field supplements the Status field (field 6). The Status field shall be set to V
= invalid for all values of Operating Mode except or A = Autonomous and D = Differential. The positioning
system Mode indicator and Status fields shall not be null fields.