based on the work of Toodles I've setup a atmel version of his Imp board. See this thread.
Here's an extarct of his post:
Most PS3+Xbox360 sticks now use a DPDT toggle switch to select which system is to be used. This setup works well, but requires a DPDT switch be purchased, and the case modified so the switch can be installed. I had mentioned previously that it would be possible to use an existing button to select with a small amount of electronic.
- plugin in the controller and press no button -> xbox360
- plugin in the controller and press guide button (example) -> ps3
No case modification needed anymore !!!
Here's the design. Feel free to comment.