For MIDIfying a rom bend you obviously need MIDI-controlled switches, preferably analog ones (bi-directional).
Since I'm not too fond of asm programming, I had to use some building blocks:
http://www.ucapps.de/A core module and each a DIN and DOUT module together with the MIDIO128 software gives you 32 digital outputs controllable by MIDI notes and/or 32 digital inputs. Hook the outputs to some digitally controlled analog switches and you got just the wanted behavior. The whole thing is expandable up to 128 digital ins and outs. It also outputs MIDI notes according to the actuated digital input and displays the output notes on the LCD. Boards and kits are available
The cheapskate I am, I made a far from perfect but simple layout:
http://lonestar.madtracker.net/Pix/cbi.jpg74HC4066 - quad high speed cmos analog switches
The horizontal pin headers are the control inputs of two chips plus ground, the vertical ones are the switch terminals.
The datasheet of the 74HC4066 gives all neccessary info about pinout.
What's left is fitting the boards into a case with a faceplate for pushbuttons and perhaps output indicator LEDs, mount MIDI and bend connections (db25 etc), done
Faceplate idea:
http://lonestar.madtracker.net/Pix/R8bendbox.jpgI have built the electronics a few months ago, the thing is running as expected.
It's quite some work but the rewards...
