BT headset on Qtopia how?

Jim Morris ml at
Tue Aug 12 08:00:08 CEST 2008

Brad Midgley wrote:
> Guys
> fwiw, it's only system audio that was half-duplex, and only on the
> neo1973. the freerunner is supposed to have a nextgen codec without
> the limitation.
> I believe everything is connected via pcm. It would be unusual to do
> it with i2s.
> The main stumbling block for me was the fact that the alsa labels for
> mixer controls did not match with the wolfson specs. It was too
> confusing to figure out what switches to throw to get audio routed, so
> I couldn't really debug the mixer settings that didn't work. That may
> be different now.
> There is a plan b, to route audio through the cpu (hci routing).
> That's how voice bluetooth audio works on desktop machines. This burns
> the battery faster and introduces delay over pcm routing. Switching to
> this mode requires a reset on the bt chip, so it's not convenient
> enough to choose it on a per-connection basis.
> On Mon, Aug 11, 2008 at 10:41 PM, Rod Whitby <rod at> wrote:
>> Jim Morris wrote:
>>> Without full schematics showing how the BT chip is connected to the Codec, and without the BT chips
>>> docs, I cannot proceed. Depending on whether the BT chip puts out PCM or I2S it may or may not work
>>> according to Wolfson, unless external circuitry has been added.
>> Does help at all?

Ok its starting to look good, I'll start working on it, I've done a lot of audio work on VOIP
systems, so long as I have all the docs I need I should be able to figure it out.

Thanks for the pointers, and sorry for the rant, I get frustrated with my FR on a daily basis ;)

Jim Morris,

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