It works great with SDM on my TX1s and my SD400, but I'd like to use it with the regular CHDK on my SD400 running 0.0-660.
It seems like the camera is setup for a normal USB and switch contact closure, but the Ricoh CA-1 is sending out pulses. Plus you get the half press.
When I press, I get the focusing sound, but it never takes the shot.
