Interactions between fmtx and bluetooth?
 

Can someone, anyone, explain the interactions between bluetooth and the FM transmitter? The problem I have is that during my commute, I use the FMTX to listen to podcasts in the car. If my bluetooth is actively paired with the N900, and I pause media playback when I am using the FMTX, the FMTX shuts itself off after about a minute. If my bluetooth set is not paired, FMTX will remain active for about 5-10 minutes.

It seems almost as if the bluetooth takes priority over the FMTX. Is there a way to reverse that so I don't have the FMTX turning itself off?

I looked at /var/lib/pulse-nokia/fmtx.parameters and /var/lib/pulse-nokia/bta2dp.parameters, but neither of them make sense to me. Can someone possibly explain the interaction between the two subsystems to me?

Thanks,
--vr

Re: Interactions between fmtx and bluetooth?
 

afaik fmtx and bluetooth are on single chip, and need some extra control for fmtx.

Re: Interactions between fmtx and bluetooth?
 

Okay, that makes sense, considering the size of the platform. Is there a way in software to, for lack of a better term, reprioritize them? So that when the fmtx is on, it takes priority over the bluetooth? Since I don't use the N900 as a phone at the moment, I would rather have the fmtx have precedence...

Re: Interactions between fmtx and bluetooth?
 

Are you using AutoDisconnect by any chance? I suspect if AD turns off Bluetooth then, since they are on the same chip, it will also turn off FMTX as a side effect.

Re: Interactions between fmtx and bluetooth?
 

I am not using autoconnect *or* autodisconnect.

And, by the way, this does not turn off the bluetooth. Let me give you a use case example. I'm driving down the road, listening to a podcast through the fmtx, when the traffic report comes on. I pause the podcast, flip to the traffic and weather report, which lasts 1-2 minutes. When I restart the podcast, either through the bluetooth headset's pause/play or from the media player's controls on the N900, it is playing through the bluetooth headset, because the fmtx has shut off.

If I were to leave it on the frequency of the fmtx, for the first minute or so, you hear the beep--beep--beep of the fmtx waiting for input, then the wash of static. The difference is that when the n900 pairing with the bluetooth headset is active, when the static starts, the fmtx has turned itself off. However, if they are not actively paired, restarting the media will restart the fmtx without interaction for a much longer period. Does that make sense?

Re: Interactions between fmtx and bluetooth?
 

I thought the modified fmtx binary stopped this issue.
I am not certain and don't use a BT headset, but worth investigating.

Re: Interactions between fmtx and bluetooth?
 

Yes, it makes sense. And it is/was the same behaviour here.
fmtx shuts down or better goes into 'sleep mode' after a while of no transmit. If you got an active bt connection paired it will switch to that one (as you described). I did not dig any deeper, but switched to fm-carkit which is one of the best packages for Maemo and imho way better than using a lousy weak low or simply run-out-of-power BT headset.
Worth a shot. Or just shut down your bt headset. You need bt enabled on N900 due to known reason ;)
Other solution I do not know. But if you investigate and come up with another idea ..... we are here.

Re: Interactions between fmtx and bluetooth?
 

Exactly. I was hoping that there was a way in software to change the priority so that if the fmtx is on, it takes precident over the bt headset.

I will give it a try, but I don't think that the fm-carkit is something that fits my use case. From what little I have had time to research, the fm-carkit is more for using the car speakers for phone calls.

Re: Interactions between fmtx and bluetooth?
 

Yeah. Sorry, but I did not say it is impossible ;)

Exactly. And it fits your use case, as it makes yout bt headset obsolete in car. Hence no problem anymore with bt precedence, just fm. Give it a try...