Controlling 25 air valves with a teensy 4.0

[colorado_hick]

I have been working on a pipe organ, takes midi messages and opens one or more air valves so a compressor can blow air into the pipe.

Is there a board that already does this? Otherwise I am looking at buying a bunch of individual solenoids and relays.

 

[BillFM]

I can't directly answer your question but you'll get plenty of answers at https://organforum.com.
They have several people who use Teensy (and Arduino's) for pipe organs (along with electronic organs).

 

[whitebengal]

Ideally, you’d want an air manifold that spoke one of the older automation standards called MODBUS RTU. There are libraries already written for this standard. If you can’t find that, I’d locate a manifold with a simple integrated wiring harness. Several companies use a simple D-Shell for attaching the raw manifold signals to a PLC. You can then attach that to a MODBUS RTU solid state relay output module to drive the manifold valves. This is the simplest method, and likely the least amount of headache, when making something controlled by a microcontroller. MODBUS RTU can easily support 25 octal output modules across RS-485. MIDI is 31.25 kbps and, depending on the modules used, MODBUS can be 9.6 kbps to 115.2 kbps, maybe faster.