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GPS Tracking

It is possible to do real-time GPS tracking using BT747.  This is different from GPS Logging which can be considered as Deferrred GPS Tracking as you can get the track at a later time.  Working with differential tracks is the main function of BT747, but live tracking is provided in the Desktop version and the Mobile Phone version (J2ME).

To do so, you will need to set up a web service such as the myLieu project (German) (possibly also see Trac (English)).  

The myLieu project has been improved and you can get the current version of BT747's myLieu as WebContent.tar.gz .  You can see that code at work on  http://mylieu.bt747.org and http://mylieu.bt747.org/viewer.php.   When you setup your own server, make sure to create a config.php file where you set the google map key (example for bt747.org):

<?php $GMAP_KEY="ABQIAAAADFJoSTzQCLixbHnZMg9AvxQ4IMxX_BgFv85tBKXNitpaLQ9wNBQddvamzC31--esGSYRR2SZLPIc6w";  ?>

Alternatively, you can use OpenLayers which you can see in action on http://mylieu.bt747.org/index_openlayer.php and http://mylieu.bt747.org/viewer_openlayer.php.

You can make a trial yourself using the mylieu.bt747.org site by configuring BT747 like indicated in the table below.  If you try these parameters, be aware that your position(s) will be memorised on the server - no guarantee is given regarding erasing them.

Host mylieu.bt747.org
Port number 80
(File ) path setUserPosition.php
Update period As you like it.  Number of seconds
User Name As you like it.
Password Not used on mylieu.bt747.org (required if you restrict your access using .htaccess).
Serve Locations Active
(or GPS Tracking active) 		 The box must be ticked to share your position on the web.

That sets up BT747 to perform HTTP GET requests.

The data transferred in the GET paramters are listed here:

HTTP GET Parameters sent by BT747
latitude: double (text) The latitude value of the current position
longitude: double (text) The longitude value of the current position.
position: double,double (text) Latitude and longitude in one parameter (example: position=50.1,3.1231)
user: text The user name
speed: float (text) The speed measured a the current position in km/h
dir: float (text) Heading (direction) in degrees.
alt: float (text) Altitude above Mean Sea Level in meters for the current position (not including geoid).
hdop: float (text) HDOP value
numsat: float (text) Number of satelites used for the position.
btaddr: XX:XX:XX:XX:XX:XX (hexadecimal text) Bluetooth address of device. Can be used to distinguish between different devices.