i kicked up kismet, with the bluetooth GPS connected, and tried to have maemo-mapper use the GPS concurrently. maemo-mapper failed to connect to the GPS, as it was the second app to try and connect to it. conversely, with maemo-mapper started first, kismet gave a warning that it was disabling GPS logging.

my question is, is it a limitation of the GPS that wont allow more than one app to connect or is it on the tablet side?

is the memory space associated with the GPS not shared/share-able? it seems that the bluetooth framework is robust enough to handle connections to more than one device, so being able to have more than one app talk to the same device would be doable.

i do notice that you can enter /dev/rfcomm0 in maemo-mapper. would that allow for multiple concurrent connections to a single GPS, or would the same effect occur, where only one app has an open connection to the device?

war-driving could be taken to a new level if you could use both kismet and maemo-mapper with a GPS at the same time.

<poking fun>
programming is easy, even though i dont do it
</poking fun>

it's not a limitation of gps modules or bluetooth in general, just that it's easier to manufacture and program bluetooth devices to pair on startup and then just connect to one device and only one device. It sucks that it's this way, but I think it would also save power (since broadcasting availability & pairing take more power than regular use).

One workaround is using gpsd. Gpsd is a daemon designed to let more than one program use nmea sentences from a gps receiver at the same time. Somebody built a version a while ago and threw it in the repository, but it doesn't install properly for me. Try that. I tried to get it working again using mud-builder, but failed.

on the n800 gpsd is installed by default. in order to use the GPS with kismet i have to connect to the device with rfcomm and launch gpsd. having done that, a second app cannot connect to get nmea data.

i will have to see if using /dev/rfcomm0 in maemo-mapper allows for additional apps to use gpsd

with the rfcomm called and a connection established with gpsd, kismet and maemo-mapper can use the one device for reporting GPS data if maemo-mappper is configured to use /dev/rfcomm0 as the GPS device.

the hitch is that if you use /dev/rfcomm0 as the GPS device in maemo-mapper, it seems that you have to manually do the rfcomm and gpsd commands, as without that, no GPS device is found.

with the version of gpsd that was made for the 770 there was a config file you could put the bluetooth mac id into and a password into another file to have the info stored.

if that could be done on the n800, and we chant/cheer/rave/pay for gnuite to modify maemo-mapper to bring up the rfcomm and gpsd connections if /dev/rfcomm0 is specified as the GPS device, then you could configure gpsd once (per install ) and have different apps talk to the GPS at the same time.

I posted a message about this very issue in the maemo forums on garage, and the reply was that maemo mapper doesn't support gpsd, but that gnuite has been meaning to add it. Hopefully he does soon, it's a great program that would be even better with gpsd support.