Wishlist/Software:GPS proxy

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Using bluetooth GPS dongle with any device is in fact nothing more than sending clear text (NMEA protocol) over serial port:

1. BT device (dongle) announces it's serial port (virtual serial port - Bluetooth SPP/SP profile)
2. BT client connects to the dongle
3. Dongle opens serial connection and send stream of NMEA data. That's all!

So let's see what NEO can do:

  • We got device equipped with GPS
  • We got very powerful bluez stack and utilities
  • We can get NMEA data
  • We can announce Serial (SPP/SP) service using bluetooth
  • and finally... we can bind GPS port with BT port and redirect NMEA to any BT client that would like to read it :)


  • We can share GPS data with anyone (Phone/Smartphone/PC/Laptop)
  • Maybe sending that data to more than one person (I don't know the exact BT capabilities)
  • Whenever you want you can use your PocketPC powered with Automapa or TomTom and don't have to buy another GPS device
  • many many more :)

I've made few tests on desktop debian and was able to get data with Holux GM-101 Handheld GPS (USB Cable) and Nokia N70 (BT)


0. Prerequisites: connect GPS unit, setup bluez and remember to pair your devices!
1. Make BT listener: rfcomm listen 0 (on my system it binds connected device to /dev/rfcomm0)
2. Announce your SP service: sdptool add sp 1
3. Run some GPS aware application on your client device
4. On successful connection rfcomm will say something like: 
Waiting for connection on channel 1
Connection from 00:**:**:**:**:** to /dev/rfcomm0
Press CTRL-C for hangup
5. cat /dev/ttyUSB0 >/dev/rfcomm0  (where /dev/ttyUSB0 is my USB to serial converter connected to GPS)
6. Should work :D 

If you can connect but there is now data:

- use "cat /dev/your_gps_device" to see if GPS is sending NMEA data to PC (for examle in holux you have to switch some options in menu)
should look something like this:

- check paring 

In a thew weeks time I should get my new Forerunner, so I will try to move this idea to Openmoko platform.

FreeRunner as GPS bluetooth device

This is described here: http://wiki.openmoko.org/wiki/GPS#GTA02 It allows to use the freerunner as ordinary BT GPS reciever. BT aware devices like navigation systems can then use the freeruners GPS signals.

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