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copied!<p>I was new to GPS aswell. Only last week i was thrown into the deep end to write a virtual serial port driver for our GPS device, and i am a recent graduate for applications programming. I did get it done, so you can to :)</p> <blockquote> <p>I assume the server on which the app is going to be installed should be equipped with a gps receiver.equipped with a gps receiver.</p> </blockquote> <p>Your application has to get the GPS data from somewhere, be it from a COM port or a nice method call in a framework. If you are working directly with the GPS output you will need to know about NMEA strings in order to translate them to a location. For read up on them i recommend the following to websites - <a href="http://teletype.com/pages/support/Documentation/RMC_log_info.htm" rel="nofollow noreferrer">http://teletype.com/pages/support/Documentation/RMC_log_info.htm</a> and <strong>only 1 link allowed</strong></p> <blockquote> <p>1) One of my question is that does the GPS receiver store the gps coordinations temporarily to be used in application</p> </blockquote> <p>As above, if your talking about direct communication with the GPS it will depend on the driver. Generally speaking the GPS device should create a set of NMEA strings and then blast these out of the device into the PC, these will then be stored in a buffer in the driver. When you request data from the driver it will delete that data from the buffer so it is not read again. i.e. GPS sends NMEA string to PC that is 960 characters long. The buffer on the driver will store those characters. You do a read and take 512 of those characters, the buffer now contains 448. If a new NMEA string is pushed out by the GPS device (960 characters again) then the buffer will be 960 characters long again. One would assume the GPS device should be kicking out new NMEA strings atleast every 5 seconds.</p> <p>Here is an example of the buffer data i got from on call to my driver. There is no signal as i was inside but it is valid data.</p> <p>GPRMC,100637.410,V,,,,,,,300908,,,N*49</p> <p>$GPGGA,100638.410,,,,,0,00,,,M,0.0,M,,0000*5F</p> <p>$GPGSA,A,1,,,,,,,,,,,,,,,*1E</p> <p>$GPGSV,3,1,12,28,89,179,,20,49,092,,08,46,237,,07,31,193,*7A</p> <p>$GPGSV,3,2,12,32,31,069,,11,27,035,,17,27,316,,04,26,239,*7B</p> <p>$GPGSV,3,3,12,23,12,118,,05,06,207,,19,05,072,,13,03,168,*70</p> <p>$GPRMC,100638.410,V,,,,,,,300908,,,N*46</p> <p>$GPGGA,100639.410,,,,,0,00,,,M,0.0,M,,000,*7C</p> <p>$GPGSV,3,2,12,19,00,000,,29,00,000,,04,00,000,,11,00,000,*7C</p> <p>$GPGSV,3,3,12,16,00,000,,28,00,000,,ü 0,000,,15,00,000,*77</p> <p>$GPRMC,100728.628,V,,,,,,,300908,,,N*4F</p> <p>$GPGGA,100729.617,,,,,0,00,,,M,0.0,M,,0000*5B</p> <p>$GPGSA,A,1,,,,,,,,,,,,,,,*1E</p> <p>$GPGSV,3,1,12,20,00,000,,10,00,000,,31,00,000,,27,00,000,*7C</p> <p>$GPGSV,3,2,12,19,00,000,,29,00,000,,04,00,000,,11,00,000,*7C</p> <p>$GPGSV,3,3,12,16,00,000,,28,00,000,,26,00,000,,15,00,000,*77</p> <p>$GPRMC,100729.617,V,,,,,,,300908,,,N*42</p> <p>$GPGGA,100730.618,,,,,0,00,,,M,0.0,M,,0000*5C</p> <p>$GPGSA,A,1,,,,,,,,,,,,,,,*1E</p> <p>$GPGSV,3,1,12,20,00,000</p> <p>So from the above, it gives several coordinates but they are all from the same time, the next time the GPS is refreshed the old data is gone. If you want to store it you need to keep polling the device for data and then store it yourself, either in memory or in a file.</p> <p>The GPS driver by Microsoft merely is a 3rd party. It connects to a com port on your behalf and gives the GPS data to anyone asking for it. The reason for this is only one app could ask for GPS data as it would be deleted on each read. If you want to keep it simple this driver is the way to go, but you still need to store the data yourself.</p> <blockquote> <p>My other question is : 3) Is there similar thing(i.e. GPS intermediate driver) available for java? If yes, which is more powerful?</p> </blockquote> <p>I have to say, i have no idea about this one</p>

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