USB_MIDI HID - very experimental! First upload of a super rough conversation of libmaple_midi -> https://github.com/feurig/libmaplemidi-cma Beware: Serial.USB is gone with this branch (for now) Setup is easy (if you have installed the original Arduino_STM32 -->https://github.com/rogerclarkmelbourne/Arduino_STM32 Just copy the repro into your Arduino/hardware folder From Arduino IDE (1.6++) choose "MIDI leaflabs maple mini Rev 2 to flash" Choose the sketch from "usb-midi-test-WORKING" After uploading your maple should be apear as MIDI device