Car Mode Application...

[Staley, Daniel L]

Bluetooth headset is not bad.  It's certainly still useable.
Hmmm....so it isnt advised to use the headset jack and the external speakers at the same time....I'm wondering, do all sounds get routed to the headset device when it is plugged in?  If it doesnt do this, surely we can configure pulseaudio to?

As for the FM transmitter, I was just going have something like this: http://www.google.com/products/catalog?hl=en&rls=com.microsoft:en-us&q=FM+transmitter&um=1&cid=8369282666750210988

So ideally, I'm going to have the car charger plugged into the usb port, the FM transmitter plugged into the headphone jack, a GPS antenna connected to the antenna port, and a bluetooth headset paired with it via bluetooth.  Haha!

It's good to hear there are no feasable problems initially.  I'm finishing up a different project I'm working on right now, and will start drawing up code flow diagrams etc soon.

One question I still have though: Is it possible to catch the incoming call signal from the GSM modem before the dialer app gets it, and handle all the call stuff in my app?  Will I need to rework all of the call taking code?  Or is there an interface into the current call taking code that I can talk to, possibly over dbus?

-Dan Staley

________________________________________
From: Joerg Reisenweber [joerg at openmoko.org]
Sent: Wednesday, May 28, 2008 12:53 AM
To: community at lists.openmoko.org
Cc: Staley, Daniel L
Subject: Re: Car Mode Application...

Am Di  27. Mai 2008 schrieb Staley, Daniel L:
> * If someone calls while the program is running, ideally I would like the
> program to pause all music etc and say "Incoming call from Fred" and display
> 2 large buttons "Ignore" and "Accept."  If accept is pressed, I want the
> phone to go into speakerphone mode, but still to route the audio to the car
> speakers.  I'm wondering if it would be possible to cancel out the repeating
> of the caller's audio back into the microphone?  I'm not up to date on my
> noise cancellation techniques ;).   If this doesnt seem plausable, just
> going into speakerphone mode, or talking through a bluetooth headset will be
> acceptable.

I think there's a decent amount of feedback killing in the GSM-module, like in
every cellphone (just has to be setup correctly), as well as in your
GSM-provider's gateway.
Furthermore you may preprocess the sound prior to routing it to the
GSM-module, by some echo-suppressor/echo-canceler.
But I think you won't be happy with the built-in mic, for usage far from
speaker in a noisy car. Probably a BT-headset is the better solution. There
are BT-speaker&mic-devices for integration in your seat's head-support,
probably worth to try.
(just a note: you must not use Freerunner speaker and headset connector
concurrently. At least using the speaker will produce unpredictable volume on
left ear channel of wired headset. Sorry I was to late to stop this for
GTA02 - wonder about ringtones :-/ When I forget to pull out the headphones
when throwing FR on the table; or when I connect FR to my stereo to play
music and a call comes in...)

The rest sounds good to me. Just curious about the FM-connection to your
car-radio... And you will need a car-USB-charger ;-)

cheers
jOERG