[maemo-developers] [maemo-developers] Bluetooth headset - not really working?

[From: Johannes Eickhold]

On Mon, 2006-01-09 at 20:04 -0700, Brad Midgley wrote:
> Johannes
> 
> The two types of bluetooth audio are very different. You linked to a
> discussion about the other type.

Sorry, I didn't made that clear enough. I was refering to the following
said in http://article.gmane.org/gmane.linux.bluez.devel/6729 by Marcel
Holtmann:

"The Nokia 770 is using a TI chip and basically nobody of us has real
experiences with these chips. I have seen them in an iPAQ and now the
770, but that's it. Do you think Nokia is willing to donate some of the
TI development kits to BlueZ? Especially the SCO and eSCO stuff needs a
lot of testing and I would prefer to do it with an i386 or x86_86 based
system."

And the answer to that in
http://article.gmane.org/gmane.linux.bluez.devel/6748 by Ville Tervo
from Nokia:

"I'll try to arrange something."

> low-latency voice-quality mono audio uses a special transport (SCO) and
> is delivered from the bluetooth chip either over the regular data
> connection to the cpu (HCI) or it is connected to dedicated audio/analog
> hardware (PCM). The HCI formatting and negotiation differs from chip to
> chip and the linux driver is only complete for CSR chipsets.

Thanks for the explanation - SCO is exectly what I need then.

> a2dp specifies one-way high-quality, traditionally stereo, audio. It is
> delivered over an L2CAP socket so linux can send and receive this audio
> with any bluetooth chip that has even the most basic support.

So that is used for bluetooth stereo earphones to listen to e.g. CD
music?

> We know what has to be done for a2dp. The SCO stuff is what I would like
> to see help from Nokia on. I would hope they can help us with the HCI
> interaction with the SCO transport since that gives us the most generic
> control over the audio stream.

Thanks for that details!

Jonek