[shr] Headset detect?

[Marcel]

Am Dienstag, 14. April 2009 14:20:26 schrieb Helge Hafting:
> Paul Fertser wrote:
> > Helge Hafting <helge.hafting at hist.no> writes:
> >> Paul wrote:
> >>> Almost sounds as if you do not push the headset connector in far
> >>> enough.
> >>
> >> I think there is something wrong with the FR headset socket.
> >> I have tried several headsets as well as several converter plugs for
> >> those headsets that have the bigger plugs.
> >>
> >> If I push the plug all the way in, I get sound in one channel only. Pull
> >> it a litle out, and I get nice stereo. Pull it some more out, and I get
> >> a very weak stereo. (Possibly missing the ground connection, so the two
> >> channels connect in series?) Pull further out, and weird things happens,
> >> sound in left only or right only, or perhaps the main speaker wakes
> >> up.
> >
> > Looks like you're trying to use incompatible 3-ring
> > adapter/headphones. Obviously that won't work.
> >
> > The right pinout of FR's receptable is:
> > tip: MIC
> > RIGHT
> > LEFT
> > GND
> >
> > If you fully push a regular 3-ring jack in the socket, you'll have MIC
> > input connected to your left headphone, RIGHT output to the right
> > headphone and you'll short LEFT to GND by the base of your
> > jack. Obviously if you pull it a little, you'll have your left
> > headphone connected to the RIGHT output, your right headphone to the
> > LEFT, and a proper ground connection.
> >
> > Use only properly wired 4-ring jack!
>
> Thanks.
> Do such converters exist at all though? I have been to quite a few phone
> shops, showing them the 3.5mm 3-ring headset connector, as well as the
> 2.5mm 4-ring earplug. (The latter works, but the headset has better bass
> and is more pleasant to wear.)
>
> No phone shop seems to have such a connector. Of course, these people
> doesn't actually seem to know that 2.5mm and 3.5mm plugs are
> standardized sizes, they keep asking what brand of phone it is. :-(
>
> Helge Hafting

There's at least one adapter known working (I own one of them), it's an MP35A 
from some Hong Kong distributor, have a look 
at:http://wiki.openmoko.org/wiki/Headset

--
Marcel