I've gotten my hands on a Sony BT GPS adapter and I wanted to see if I could use it with my N810. On the computer you have to configure applications to use COM40 in order for the GPS adapter to work correctly. Is there any way for me to do this in Maemo Mapper? I'm not sure if this BT GPS adapter will work with the N810 or if its proprietary to Sony products.

The complication of COM assignment is a Windows specific problem. Bluetooth in Linux does not use "virtual" com ports. In order to connect the Sony BT GPS adapter, just use the "GPS" control panel app to pair the GPS with the Nokia. That should make it available to all software that uses GPS on the Nokia.

Martin

Thanks m_stolle, I was able to pair it up and it does a hot lock on of satellites in about 10 seconds (including the time it takes to pair to the BT adapter). I get an error sometimes though that says something along the lines of "NMEA input not valid". After a 30 seconds or so, my track in Maemo Mapper seems to think I instantly traveled several hundred miles to the east and back. Any idea what is causing this? (I'm assuming its the adapter, any known fixes?)

I am not sure if the "NMEA input not valid" and the bad positions are related or not, but they could be. GPS systems output text data in a format specified by the NMEA. There are many different data sentences it can output and it's possible that some of them are not understood by Maemo Mapper (hence the error message). Alternatively, I think some (all?) NMEA sentences have checksums and/or give quality/validity information abotu the data they are providing. The error message can hence also indicate that the checksum failed or that the GPS marked some data as invalid. I find it highly unlikely that any checksums fail - usually NMEA is exchanged via 3-wire serial ports with no error correction whatsoever - hence the checksums. However, Bluetooth has its own checksum/retransmission protocol, so the data seen by any application should be completely error free. So it could possibly that the GPS is providing position data but is also marking it as invalid due to poor signal strength. That would also explain why the position is off in Maemo Mapper. I am guessing that is an intermittent thnig? You might want to talk to the Maemo Mapper author and/or file a bug report. It shouldn't make your position move by hundreds of miles if the GPS marked the data as invalid... Of course, it's also possible that the GPs doesn't catch all its error and that it sometimes provides bad data without marking it as invalid. Then it's just a limitation of the GPS receiver and you'll just have to live with occasional artifacts (although technically, Maemo Mapper could use heuristic checks to filter hundred miles jumps out...)

Martin