>> You realise that MIDI is a serial communications protocol, right? It's
>> not like you just connect each sensor to a different pin on the plug;
>> you need some fairly elaborate electronics in there.
> 
> At the very simplest form, one input pin on any ol' micro-controller for
> each pedal.

Micro-controller? Ouch.

> Controller can just poll each
> pin, or batches of pins where speed is an issue, and create the MIDI
> packet to send.

Not quite.

MIDI sends note-on and note-off messages, so the controller needs to 
"remember" the previous pin state to decide whether anything has changed.

> Just make sure to have an optoisolator on
> . . . crud, it has been forever since I did anything MIDI, I don't
> remember if it is on the TX or RX wire.

MIDI is simplex, not duplex. A single MIDI cable carries messages in one 
direction only. And I'm pretty sure it's the receiving end that's 
supposed to be opto-isolated. (I.e., I don't have to do anything.)



> Elaborate? $8 micro-controllers are absurdly powerful now, and very easy
> to program. Granted, most of the time it is assembly or some odd looking
> java-esque language, but GCC will cross-compile to AVR and ARM chips.
> The soldering might be tough, but for a prototype just breadboard it.

1. I'd be very surprised if you can buy any sort of microcontroller for 


2. A microcontroller on its own isn't going to do much good - unless I 
also go out and buy a RAM ship and either a PROM and burner or some 
flash RAM. I would think a PIC would be the way to go.

3. Even a PIC is probably vastly too difficult to program. And if it 
doesn't work? It's not like you can debug it...

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