7
/
49
field is omitted, but the delimiting commas are still there, with no space between
them.
The data may vary in the amount of precision contained in the message. For example
time might be indicated to decimal parts of a second or location may be show with 3
or even 4 digits after the decimal point. Programs that read the data should only use
the commas to determine the field boundaries and not depend on column positions.
1.2.3
GGA Sentence Format
GGA sentences contain Global Positioning System Fix Data, including Time, Position
and fix related data for a GPS receiver.
$GxGGA,<1> ,<2>,3>,4>,5>,6>,7>,8>,9>,10>,11>,12>,13>,14>*xx<CR><LF>
Gx: NMEA taker identifier. Different identifier can be applied according to user
configuration, e.g. GP, GN, GL, and BD
<1> Time (UTC), format: hhmmss.ss
<2> Latitude, format ddmm.mmmm
<3> N or S (North or South)
<4>Longitude, format ddmm.mmmm
<5>E or W (East or West)
<6>GPS Quality Indicator: 0: unknown 1: single point positioning, 2 DGPS, 3 invalid
PPS, 4 RTK fixed solution, 5: RTK float solution, 6: Estimating 7: user constrained
positioning 8: Simulation 9: WAAS
<7>Number of satellites in view
<8> Horizontal Dilution of precision
<9> Antenna Altitude above/below mean-sea-level (geoid)
<10> Units of antenna altitude, meters
<11> Geoidal separation, the difference between the WGS-84 earth ellipsoid and
mean-sea-level (geoid), "-" means mean-sea-level below ellipsoid
<12> Units of geoidal separation, meters
<13>Age of differential GPS data, time in seconds since last SC104 type 1 or 9
update, null field when DGPS is not used
<14> Differential reference station ID, 0000-1023
* end of sentence
xx checksum of the all ASCII code
<CR><LF> carriage return and line feed
Example:
