https://twitter.com/tnt/status/1335354626791665671

tnt @tnt

Turned my #fomu into a usb sound card with midi output and also stereo headphones out. (USB audio spec compliant so all works out of the box)

Code is now upstream :

• FOMU support in no2bootloader (alternate to foboot, better imho for single purpose projects) https://github.com/no2fpga/no2bootloader/

• USB Audio code (hw/fw) in https://github.com/smunaut/ice40-playground/tree/master/projects/usb_audio with support for fomu/icebreaker/bitsy

Ping if you want help port to other boards

Pepijn de Vos @pepijndevos

Wait how do you connect anything to the fomu? Solder wires to these capacitive tabs?

tnt @tnt

Yeah, I soldered to the 4 IOs.

• #1 is wired as a button for DFU recovery (wired to a N/C pin of DIN plug)
• #2&3 are wired as PDM audio out with RC filter & DC block cap to the 3.5mm jack
• #4 is wired as the MIDI TX pin