NMEA 0183
There is a very short Wikipedia entry on NMEA 0183. A much better explanation is at aprs.gids.nl or in this PDF by Klaus Betke. There is also a list of obsolete NMEA 0183 sentences . It is not very complicated to write a parser, but microcontrollers require a small footprint. The TinyGPS library is just perfect - a great compromise between space and functionality.
| Currently Parsing | Redundant | Satellite Information | ||||||
| Chip | Baud | $GPGGA | $GPRMC | $GPGLL | $GPVTG | $GPGSA | $GPGSV | |
| Adafruit | MTK3329 | 9600 | x | x | x | x | x | |
| Sparkfun | LS20031 | 57600 | x | x | x | x | x | x |
| GPSBee | u-blox 5 | 9600 | x | x | x | x | x | x |
$GPGGA,200401.000,4308.7554,N,07734.5586,W,1,5,1.46,161.4,M,-34.4,M,,*66 $GPRMC,200401.000,A,4308.7554,N,07734.5586,W,0.34,81.99,250312,,,A*47
GGA Global Positioning System Fix Data. Time, Position and fix related data for a GPS receiver
$--GGA,hhmmss.ss,llll.ll,a,yyyyy.yy,a,x,xx,x.x,x.x,M,x.x,M,x.x,xxxx*hh
1) Time (UTC)
2) Latitude
3) N or S (North or South)
4) Longitude
5) E or W (East or West)
6) GPS Quality Indicator, 0 - fix not available, 1 - GPS fix, 2 - Differential GPS fix
7) Number of satellites in view, 00 - 12
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
15) Checksum
RMC Recommended Minimum Navigation Information $--RMC,hhmmss.ss,A,llll.ll,a,yyyyy.yy,a,x.x,x.x,xxxx,x.x,a*hh 1) Time (UTC) 2) Status, V = Navigation receiver warning 3) Latitude 4) N or S 5) Longitude 6) E or W 7) Speed over ground, knots 8) Track made good, degrees true 9) Date, ddmmyy 10) Magnetic Variation, degrees 11) E or W 12) Checksum
LS20031
You can buy a LS20031 from SparkFun for $60. This is a 32 Channel 5Hz GPS Receiver made by Locosys Technology.
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