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Retrieved from "http://wiki.openmoko.org/wiki/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 :)

Profits: 

- 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)


Holux----(USB)--->Debian-----(BT)---->Nokia 


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:
PGSA,A,2,19,18,,,,,,,,,,,0.0,0.0,0.0*32
$GPGSV,3,1,11,03,71,207,23,06,66,169,22,22,64,137,31,19,57,289,32*7F
$GPGSV,3,2,11,18,46,065,33,21,21,082,00,16,11,193,00,15,11,025,00*75
$GPGSV,3,3,11,08,08,319,00,14,05,142,00,26,05,011,00*44
$GPRMC,225506.064,
- check paring

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