What I have so far




My console has been picked up from the dealer, but won't get delivered to me till next week. That gives me time to work on the electronics.  I have a working prototype of the midi scanner for the pedalboard.

My plan is to hook up the pedalboard first - partly because I expect it to be easier, the mechanism is bigger, more accessible, and there's a lot less of them.  Mostly though I would really like to have a working pedalboard to play with while I'm working out what to do about the manuals and stops.

My design uses an Metro Mini from Adafruit for the controller and a pair of MCP23017 port expander chips available from your favorite supplier.

The cable connects to a usb port on my mac, which is running Hairless Midi Bridge

I have small array of pushbuttons standing in for pedals and it works - when I push a button, the correct note sounds in Hauptwerk, Grand Orge, Garage Band, or whatever.  Woohooo!

I will upload the code to github, but right now it's in a very primitive state. I'm using code from tttapa's MIDI Controller library but it doesn't support the MCP23017 so I sort of borrowed the bits I needed for actual midi encoding and left the controller class behind.  In theory I could have expanded the class to add support for my chip but I wasn't feeling that patient.

When the organ arrives and I get a chance to dig around inside, I'll figure out what I'm going to do about power and if I can use the existing pedal contacts as-is or if I've got to add switches. I would like to do the simplest solution leveraging as much of the existing electrical circuits as possible and leave upgrading to fancy hall sensors and whatnot for the future.

Next...


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