MIDI Test

Example source: examples/device/midi_test

A USB MIDI device that continuously plays a fixed melody, useful for verifying USB MIDI enumeration and streaming.

What it does

• Sends a repeating sequence of note-on / note-off messages (cable 0, channel 1) about every 286 ms.

• Drains any incoming MIDI packets (read and discarded) so the host sender never blocks on a full input port.

• Blinks the board LED to indicate USB state (not mounted / mounted / suspended).

USB Descriptors

Interface	Class driver
0–1	MIDI (Audio Control + MIDI Streaming)

Configuration

Notable tusb_config.h settings:

#define CFG_TUD_MIDI              1
#define CFG_TUD_MIDI_RX_BUFSIZE   (TUD_OPT_HIGH_SPEED ? 512 : 64)
#define CFG_TUD_MIDI_TX_BUFSIZE   (TUD_OPT_HIGH_SPEED ? 512 : 64)

Building

CMake:

mkdir build && cd build
cmake -DBOARD=raspberry_pi_pico ..
cmake --build .

Make:

make BOARD=raspberry_pi_pico all

FreeRTOS variant

A FreeRTOS build is in examples/device/midi_test_freertos — identical MIDI melody playback, with the device, MIDI, and LED-blink work split across FreeRTOS tasks.

Try it

The device shows up as a MIDI port. On Linux, list ports with aseqdump -l, then watch the incoming stream with aseqdump -p <client:port> (you should see a steady run of note on/off events), or route the port into a synth such as FluidSynth/qsynth to hear the melody.