[ gpsdrive ] bluetooth gps

[Andrew Walbran]

On Thu, Oct 22, 2009 at 8:26 AM, Roger Lees <leesroger at gmail.com> wrote:
> I recently bought a Bluetooth
> GPS receiver and used it with Navigator 8 on Windows.  It worked
> straight away.  I downloaded GPSdrive, and it doesn't recognise my GPS
> receiver.  I think I know why after checking around the forums.  The
> program uses gpsd, and is looking for a receiver via USB, which it
> cannot see.  The answer I discover is to modify files in the Bluetooth
> directory.  Now, I can probably do that, but in order to do so I am
> going to have to learn a bit about how Linux works because not only
> don't I know how to find the relevant files, I don't know how to get at
> the command line.  I know all the Linux buffs will be sucking their
> teeth and dredging up their most sarcastic remarks, but it has been a
> long time since I had to alter a Windows program to get it to work.
> They just do, and if they don't there is always another one that will.
> I am too old (61) to learn how to tweak Ubuntu programs.  GPSdrive looks
> like a good program.  There is another Linux program on Ubuntu,
> TangoGPS, which also looks like a lot of fun to use with exactly the
> same problem.  I realise that all of these programs are free and
> therefore it is pointless complaining and/or moaning about the efforts
> of people who are giving their skills and time for nothing, but if Linux
> and Open Source programs are going to eventually replace Microsoft (and
> I hope they do) they need to work for people like me who don't want to
> indulge in programming at however simple a level to get them started.
> After all, you don't expect to have to fiddle with your car's engine
> before you can drive it away.  Or should you?  Which is a very long way
> round asking if GPSdrive (or gpsd) could be amended to include Bluetooth
> GPS receivers.  Please.

As other posters have said, gpsd is responsible for connecting to your
GPS, and then all programs which need to access it (such as gpsdrive)
can just connect to gpsd.
The way bluetooth GPS receivers generally work is that they show up as
a bluetooth serial port. The first step, then, is to connect to this.
Assuming your bluetooth adapter is working properly, you should be
able to run
$ hcitool inq
to scan for all available bluetooth devices. From this copy the MAC
address of your GPS receiver (a MAC address looks something like
01:23:45:67:89:ab), and run a command like this (substituting the
correct MAC address):
$ rfcomm connect 0 01:23:45:67:89:ab
That will connect to your GPS receiver and call the serial port
/dev/rfcomm0. You can then start gpsd on this serial port as usual:
$ gpsd /dev/rfcomm0
And after all that, assuming there are no errors, start GPSdrive and
it should connect to gpsd and get your fix.

I agree that it would be nice if GPSdrive had a button to
automatically detect bluetooth GPSes, connect to them and start gpsd.


-- 
Andrew Walbran
website: http://q.geek.nz/
blog: http://qwandor.wordpress.com/