GPS with JGPS - Setup Testing

I am playing around the GPS module since quite some time and got a new JGPS java api to interact with. I have a serial out put GPS module. Check out my GPS setup. This particular API has got a very good interface for USB, Serial and bluetooth GPS devides.This has native API for both Unix and windows platform. In unix plat form this supports both linux and solaris. This API has got a very meaning full instruction to setup in unix environment. As I have my java comm API already setup to windows and I have the USB - Serial driver for windows, I tested in windows rather than ubuntu.

This api works on the top of java comm api. I was controlling my GSM/ GPRS modem through  the IO channels using java comm api. In the older versions of jGPS, the io interaction to the GPS module was through Java comm api and the jGPS was only the formatter. But this new release integrated the Java comm api with it again with some additional interface like bluetooth.

So general architecture is as follows.

GPS Module - Serial/ USB/ Bluetooth Interface - Java Comm API (JAVA+Native API[OS specific]) - jGPS API (JAVA)

Following is a simple program to register to one of the event and get notified for the lat/lng.

Source


package org.satish.practice;



import com.uf.gps.Descriptor;
import com.uf.gps.GPSListener; 
import com.uf.gps.GPSEvent; 
import com.uf.gps.Position;
import com.uf.gps.protocols.NMEA.NMEAHandler; 
import com.uf.gps.Connection; 
import com.uf.gps.ConnectException; 
import javax.comm.SerialPort;

public class myApp implements GPSListener { 
public myApp () { 

NMEAHandler nh = null; 
/* Initialize a connection handler on the RS232 interface */ 
try { 
nh = new NMEAHandler(1,"myApp","COM6",9600, SerialPort.DATABITS_8, SerialPort.STOPBITS_1, SerialPort.PARITY_NONE); 
} catch (ConnectException x) { 
// Something is going wrong
} 
/* Enable reception of GPSEvents */ 
nh.registerListener( this ); 
}

public static void main(String[] args) throws ConnectException { 
myApp my = new myApp(); 
}

public void actionPerformed(GPSEvent ev) { 
Position p = null; 
/*
* public GPSEvent (Connection src, int transactiontype, int datatype, Object
* data)
*/ 
/* src: connection handler, maybe there's more than one defined */
/* transactiontype: is one of BEGIN_TRANS, END_TRANS, _TRANS */ 
/* datatype: one of the _CLASS constants, which classifies a data type */ 
/* data: the GPSObject */ 

if (ev.getTransType() == GPSEvent.POS_TRANS) { 
p = (Position) ev.getData(); 

/* Every high level class has lots of properties */
Descriptor wa = p.getProperty("LONGITUDE"); 
Descriptor wb = p.getProperty("LATITUDE"); 

/* wa.getValue of class Double */ 
String lon = wa == null ? "" : (String) wa.getValue().toString(); 

/* wb.getValue of class Double */ 
String lat = wb == null ? "" : (String) wb.getValue().toString(); System.out.println( "Latitude/Longitude = [" + lat + "][" + lon + "]" ); 
} else if (ev.getTransType() == GPSEvent.WPT_TRANS) { 
// .................................................. 
}
}
}

Output

Latitude/Longitude = [12.957963999999999][77.67056266666667]

Latitude/Longitude = [12.957963999999999][77.67056266666667]
Latitude/Longitude = [12.957967][77.67056366666667]
Latitude/Longitude = [12.957967][77.67056366666667]
Latitude/Longitude = [12.957972][77.67056166666667]
Latitude/Longitude = [12.957972][77.67056166666667]
Latitude/Longitude = [12.95797][77.67056366666667]
Latitude/Longitude = [12.95797][77.67056366666667]
Latitude/Longitude = [12.957965][77.67056366666667]
Latitude/Longitude = [12.957965][77.67056366666667]
Latitude/Longitude = [12.957963][77.67056366666667]
Latitude/Longitude = [12.957963][77.67056366666667]
Latitude/Longitude = [12.957961999999998][77.67056466666668]
Latitude/Longitude = [12.957961999999998][77.67056466666668]
Latitude/Longitude = [12.957961999999998][77.67056466666668]
Latitude/Longitude = [12.957961999999998][77.67056466666668]
Latitude/Longitude = [12.95796][77.67056666666667]
Latitude/Longitude = [12.95796][77.67056666666667]
Latitude/Longitude = [12.957958999999999][77.67056866666667]
Latitude/Longitude = [12.957958999999999][77.67056866666667]
Latitude/Longitude = [12.957958999999999][77.67056966666667]
Latitude/Longitude = [12.957958999999999][77.67056966666667]
Latitude/Longitude = [12.957961999999998][77.67057066666668]
Latitude/Longitude = [12.957961999999998][77.67057066666668]
Latitude/Longitude = [12.957958999999999][77.67057266666667]
Latitude/Longitude = [12.957958999999999][77.67057266666667]


I will still be playing around the API and keep posting too.

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NMEA GPS Reads

GPS modules typically put out a series of standard strings of information, under something called the National Marine Electronics Association (NMEA) protocol. More information on NMEA standard data strings can be found at this site.
GPS receiver gives the reading starting with the following strings and each string appended data has its own significant.

$GPGGA: Global Positioning System Fix Data
$GPGSV: GPS satellites in view
$GPGSA: GPS DOP and active satellites
$GPRMC: Recommended minimum specific GPS/Transit data


Each of these sentences contains a wealth of data. For example, here are a few instances of the $GPRMC string.




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 = Valid position, 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, degrees true
           191194      UTC 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. for NMEA 0183 version 3.00 active the Mode indicator field is added




$GPRMC,hhmmss.ss,A,llll.ll,a,yyyyy.yy,a,x.x,x.x,ddmmyy,x.x,a,m*hh




Field #


 1 = UTC time of fix
 2 = Data status (A=Valid position, V=navigation receiver warning)
 3 = Latitude of fix
 4 = N or S of longitude
 5 = Longitude of fix
 6 = E or W of longitude
 7 = Speed over ground in knots
 8 = Track made good in degrees True
 9 = UTC date of fix
 10= Magnetic variation degrees (Easterly var. subtracts from true course)
 11= E or W of magnetic variation
 12= Mode indicator, (A=Autonomous, D=Differential, E=Estimated, N=Data not valid)
 13   = Checksum




The full documentation you can get here.

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GPS Receiver Module - iW-GPS-01

Got iW-GPS-01(with Active Antenna) and iWave's GPS Platforms. The GPS board is mounted on a GPS platform with serial out and has a external antenna. The board has got a serial port and a power input.The board operates on 5 - 35 V input.

Full specification attached here.

Reads I got from Hiper Terminal.

$GPGSA,A,3,14,06,24,03,30,31,21,22,,,,,2.1,1.0,1.8*3D
$GPGSV,3,1,12,31,72,201,17,22,47,056,15,24,38,314,26,14,37,004,24*72
$GPGSV,3,2,12,18,26,093,,30,26,106,24,06,17,219,25,25,16,084,19*73
$GPGSV,3,3,12,19,14,265,,21,13,150,22,03,13,232,27,16,06,191,*7C
$GPRMC,181611.000,A,1257.7947,N,07740.3910,E,0.16,57.21,231010,,,A*54
$GPVTG,57.21,T,,M,0.16,N,0.3,K,A*38
$GPGGA,181612.000,1257.7948,N,07740.3910,E,1,08,1.0,916.6,M,-88.4,M,,0000*75
$GPGSA,A,3,14,06,24,03,30,31,21,22,,,,,2.1,1.0,1.8*3D
$GPRMC,181612.000,A,1257.7948,N,07740.3910,E,0.40,131.00,231010,,,A*69
$GPVTG,131.00,T,,M,0.40,N,0.7,K,A*0D
$GPGGA,181613.000,1257.7946,N,07740.3911,E,1,08,1.0,917.4,M,-88.4,M,,0000*78
$GPGSA,A,3,14,06,24,03,30,31,21,22,,,,,2.1,1.0,1.8*3D
$GPGSV,3,1,12,31,72,201,17,22,47,056,14,24,38,314,26,14,37,004,24*73
$GPGSV,3,2,12,18,26,093,,30,26,106,24,06,17,219,25,25,16,084,19*73
$GPGSV,3,3,12,19,14,265,,21,13,150,22,03,13,232,27,16,06,191,*7C
$GPRMC,181613.000,A,1257.7946,N,07740.3911,E,0.74,149.98,231010,,,A*6E
$GPVTG,149.98,T,,M,0.74,N,1.4,K,A*06


Some pictures of my setup.

Let play around it. 

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