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:
   $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






NameExample DataDescription


Sentence Identifier$GPGGAGlobal Positioning System Fix Data


Time17083417:08:34 Z


Latitude4124.8963, N41d 24.8963' N or 41d 24' 54" N


Longitude08151.6838, W81d 51.6838' W or 81d 51' 41" W


Fix Quality:
- 0 = Invalid
- 1 = GPS fix
- 2 = DGPS fix1Data is from a GPS fix


Number of Satellites055 Satellites are in view


Horizontal Dilution of Precision (HDOP)1.5Relative accuracy of horizontal position


Altitude280.2, M280.2 meters above mean sea level


Height of geoid above WGS84 ellipsoid-34.0, M-34.0 meters


Time since last DGPS updateblankNo last update


DGPS reference station idblankNo station id


Checksum*75Used by program to check for transmission errors









$GPGSA

GPS DOP and active satellites


eg1. $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 data


eg1. $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    = Checksum


The 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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