DIY Car-handsfree

[ohault]

I'm loooking for more information about the DIY Car-handsfree at
http://wiki.xda-developers.com/wiki/Connectors for building a single connector for QTEK/XDA in-car solution.

audio out => build-in car radio input
mic => external mic
rs232 or USB => command the internal car bus (e.g; I-bus in a BMW http://www.openbmw.org/bus/ ) or GPS
power => charging the device

Anyone has already explored theses topics.

Olivier

[Pope]

On the http://wiki.xda-developers.com/wiki/Connectors page, there is already a schematic for making a connector which has power, microphone and speakers for handsfree, so all you would need is to then connect the serial lines to the correct plug for your BMW's car bus