GPS sentence
Have been working on GPS with Arduino few years ago, recently there is a tinyGPS++ library..
which increase the ability to decode more sentences....
First need to review what are the sentnece, each sentence contain different info,
http://aprs.gids.nl/nmea/
basic 19 sentences:
which increase the ability to decode more sentences....
First need to review what are the sentnece, each sentence contain different info,
http://aprs.gids.nl/nmea/
basic 19 sentences:
$GPBOD - Bearing, origin to destination $GPBWC - Bearing and distance to waypoint, great circle $GPGGA - Global Positioning System Fix Data $GPGLL - Geographic position, latitude / longitude $GPGSA - GPS DOP and active satellites $GPGSV - GPS Satellites in view $GPHDT - Heading, True $GPR00 - List of waypoints in currently active route $GPRMA - Recommended minimum specific Loran-C data $GPRMB - Recommended minimum navigation info $GPRMC - Recommended minimum specific GPS/Transit data $GPRTE - Routes $GPTRF - Transit Fix Data $GPSTN - Multiple Data ID $GPVBW - Dual Ground / Water Speed $GPVTG - Track made good and ground speed $GPWPL - Waypoint location $GPXTE - Cross-track error, Measured $GPZDA - Date & Time
check out my G top MTK gps module, it sends out 4 sentenses:
$GPGGA,000022.317,,,,,0,0,,,M,,M,,*4D<CR><LF> $GPGSA,A,1,,,,,,,,,,,,,,,*1E<CR><LF> $GPRMC,000022.317,V,,,,,0.00,0.00,060180,,,N*47<CR><LF> $GPVTG,0.00,T,,M,0.00,N,0.00,K,N*32<CR><LF>
$GPGGA
| Name | Example Data | Description |
|---|---|---|
| Sentence Identifier | $GPGGA | Global Positioning System Fix Data |
| Time | 170834 | 17:08:34 Z |
| Latitude | 4124.8963, N | 41d 24.8963' N or 41d 24' 54" N |
| Longitude | 08151.6838, W | 81d 51.6838' W or 81d 51' 41" W |
| Fix Quality: - 0 = Invalid - 1 = GPS fix - 2 = DGPS fix | 1 | Data is from a GPS fix |
| Number of Satellites | 05 | 5 Satellites are in view |
| Horizontal Dilution of Precision (HDOP) | 1.5 | Relative accuracy of horizontal position |
| Altitude | 280.2, M | 280.2 meters above mean sea level |
| Height of geoid above WGS84 ellipsoid | -34.0, M | -34.0 meters |
| Time since last DGPS update | blank | No last update |
| DGPS reference station id | blank | No station id |
| Checksum | *75 | Used by program to check for transmission errors |
$GPGSA
GPS DOP and active satelliteseg1. $GPGSA,A,3,,,,,,16,18,,22,24,,,3.6,2.1,2.2*3C eg2. $GPGSA,A,3,19,28,14,18,27,22,31,39,,,,,1.7,1.0,1.3*35 1 = Mode: M=Manual, forced to operate in 2D or 3D A=Automatic, 3D/2D 2 = Mode: 1=Fix not available 2=2D 3=3D 3-14 = IDs of SVs used in position fix (null for unused fields) 15 = PDOP 16 = HDOP 17 = VDOP$GPRMC
Recommended minimum specific GPS/Transit dataeg1. $GPRMC,081836,A,3751.65,S,14507.36,E,000.0,360.0,130998,011.3,E*62 eg2. $GPRMC,225446,A,4916.45,N,12311.12,W,000.5,054.7,191194,020.3,E*68 225446 Time of fix 22:54:46 UTC A Navigation receiver warning A = OK, V = warning 4916.45,N Latitude 49 deg. 16.45 min North 12311.12,W Longitude 123 deg. 11.12 min West 000.5 Speed over ground, Knots 054.7 Course Made Good, True 191194 Date of fix 19 November 1994 020.3,E Magnetic variation 20.3 deg East *68 mandatory checksum eg3. $GPRMC,220516,A,5133.82,N,00042.24,W,173.8,231.8,130694,004.2,W*70 1 2 3 4 5 6 7 8 9 10 11 12 1 220516 Time Stamp 2 A validity - A-ok, V-invalid 3 5133.82 current Latitude 4 N North/South 5 00042.24 current Longitude 6 W East/West 7 173.8 Speed in knots 8 231.8 True course 9 130694 Date Stamp 10 004.2 Variation 11 W East/West 12 *70 checksum eg4. $GPRMC,hhmmss.ss,A,llll.ll,a,yyyyy.yy,a,x.x,x.x,ddmmyy,x.x,a*hh 1 = UTC of position fix 2 = Data status (V=navigation receiver warning) 3 = Latitude of fix 4 = N or S 5 = Longitude of fix 6 = E or W 7 = Speed over ground in knots 8 = Track made good in degrees True 9 = UT date 10 = Magnetic variation degrees (Easterly var. subtracts from true course) 11 = E or W 12 = Checksum
$GPVTG
Track Made Good and Ground Speed.
eg1. $GPVTG,360.0,T,348.7,M,000.0,N,000.0,K*43 eg2. $GPVTG,054.7,T,034.4,M,005.5,N,010.2,K 054.7,T True track made good 034.4,M Magnetic track made good 005.5,N Ground speed, knots 010.2,K Ground speed, Kilometers per hour eg3. $GPVTG,t,T,,,s.ss,N,s.ss,K*hh 1 = Track made good 2 = Fixed text 'T' indicates that track made good is relative to true north 3 = not used 4 = not used 5 = Speed over ground in knots 6 = Fixed text 'N' indicates that speed over ground in in knots 7 = Speed over ground in kilometers/hour 8 = Fixed text 'K' indicates that speed over ground is in kilometers/hour 9 = ChecksumThe actual track made good and speed relative to the ground.
$--VTG,x.x,T,x.x,M,x.x,N,x.x,K x.x,T = Track, degrees True x.x,M = Track, degrees Magnetic x.x,N = Speed, knots x.x,K = Speed, Km/hr
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