MIDI Switcher-20 button

[Jurqr]

Hello
I'm looking for some help or advices in building midi foot controller
I've got i'd say some knowledge into electronics and pedals, but I'm a total newbie into midi.
I've bought T-rex Spin Doctor Guitar preamp, which can be midi-controlled.
I was and still am thinking about building ~20 switches foot controller, to add "more channels" to this preamp.
As far as i understand I need a footswitch which sends notes (program change) to the preamp.
I have no idea thou' how to make every button to switch off the previously chosen channel and engage new one with one button. Should it be only programmed?
Thanx for help
JJ

[potul]

You need to use a momentary switches (not latching), and use a microcontroller to monitor when a switch is pressed and send the corresponding MIDI message.

[composition4]

If you don't want to get into programming a microcontroller too much, take a look at something like this:

http://store.highlyliquid.com/products/midi-cpu

Pretty much ready to go for your needs, all you need to do is supply the hardware

Jonathan

[Jurqr]

Thanks to both of You.
The second pre-programmed board would be sth for.me I think.
I,ve got one more question. Does it come with documentation about the connections to the certaainins/outs in the pcb
JJ

[composition4]

Cmon you have to at least TRY to have a look for yourself! 

But in case you have looked it the link that says "Hardware User Manual" right there on the front page... http://highlyliquid.com/support/docs/pdf/MIDI-CPU-Hardware-Rev-K.pdf

Looks like you want to read page 3

Jon