• Hardware
  • I want to use puredata and recieve midi from GPIO.

Since I am already using USB for other purposes, I would like to receive MIDI via GPIO and reflect it in puredata. But I don't know how to do it at all.

If your midi device has usb maybe the best option is to use a usb hub, which may have to be powered externally. If you want to do the effort of assembling the analog midi circuit - considering Bela's gpios are limited to 3.3V, that achievable, too.