the Firmware Manual for it has a ton of info on how it can convert MIDI msg's into Digital Potentiometer and 5v Logic control.
---In korgpolyex@yahoogroups.com, <ultragalore@...> wrote :
I have succesfully used a Teensy to process midi messages. This might be a board you would like to check out. It's in fact a small Arduino with USB.
Cool thing is you can program the teensy to be any usb device you want. You could plug it into your computer and make it act as a midi interface (with built in NJM in this case) AND have a midi port attached to it for standalone control. On top of that you can connect pots and switches to the board.
There's already a good library for handling MIDI messages which would probably make your project a lot easier. Check them out, there are different Teensy flavours (CPU power and i/o ports differ) (but all are not expensive at all).