Pedalboard wiring?

I’ve recently been lucky enough to acquire a large 3m drawstop console - a Wyvern C356.

I’ve got 2.98 of the manuals modified (3 notes on the great just don’t want to work even after a good scrub with isopropyl), and now moving on to the pedals.

I’m struggling to work out the pedal scheme; it has the following sets of wires on 3 separate connectors:

Black/Red/Black - but only 1 of the black goes to the pedalboard itself as far as I can tell.
Yellow/green
4 coloured wires

I had assumed that the red/black would be +/-; if I wire that up, then the remaining 6 wires all conduct to that black/ground.

If that is how they wire, I’m confused as to how I can get 32 notes out of the remaining 6 wires that all seem to go to ground.

Any ideas much appreciated!

Photos:

https://photos.app.goo.gl/FWNVbohQuZFfRQmY6

https://photos.app.goo.gl/eaoCdKzVjoSSy2Ty8

And at the pedalboard end - https://photos.app.goo.gl/YF4AUfN6LdgnoSTE6

There is a MIDI input board at the pedals as shown in the last photo. There is a SPI interface connecting the input board to the organs MIDI encoder. That circuit is easily handled by the six colored wires.

There's no MIDI on this organ at all.

I believe it's using shift registers (4 wired in, 1 spare), but the pin out of the TI chips doesn't seem to match with what my multimeter is telling me; literally everything connects to ground...

I've decided to just take the switch input wires and connect them to an arduino, then will use an ethernet cable/socket to make it detachable from the console. (the arduino will connect to the master arduino for the console via serial, so just two wires, plus +/-)

The SPI circuit doesn't use MIDI encoding of course. Whether or not the SPI data is ever converted to MIDI is irrelevant. A qualified technician could look at the data out (MISO) signal and see if all the keys are working at the cable from the PCB mounted on the pedal frame. This is a troubleshooting task that requires electronics training.

Hi Adrian,
from the last picture, the wiring is common ground to the pedal notes (green wire from plug.) There are 32 individual black wires from the pedals to the wyvern board. If you remove the built-in board, you should be able to substitute it for a parallel scan Arduino that sends MIDI where you want it.
(I tried to say this on FB, but it rejected my answer because I refuse to put my picture on public pages...)

T.

Thanks all. I decided I could spend a long time working out the serialisation, or just spend an hour patching it in to an arduino. So I chose the latter. I reused the original wiring and connector back to the console, so the arduino connects to my “master arduino” over serial, and gets 5v power down that connector.

Whilst I was there I replaced the 4x100k pots on the swell shoes with 10ks and got them up and running, so as a HW console, it’s now doing pretty well.

Next up, the stops/solenoids. Never done solenoids before, so that’s going to be interesting/challenging…