midi2cpp | Device MIDI 2.0
Full-spec USB MIDI 2.0 device on the Daisy Seed (STM32H750, Cortex-M7 @ 480 MHz). First libDaisy recipe in midi2cpp. The libDaisy fork carries USB MIDI 2.0 descriptors and raw UMP I/O only; all MIDI 2.0 logic lives in the recipe via midi2::Device. libDaisy makefile build, no Arduino IDE.
| Field | Value |
|---|---|
| VID:PID | 0483:5740 (STMicro / Daisy Seed, inherited from the libDaisy fork) |
| Product | Daisy Seed MIDI 2.0 |
| Endpoint Name | DaisySeed |
| Product Instance ID | DaisySeed-showcase-0001 |
| MIDI-CI Manufacturer ID | {0x7D, 0x00, 0x00} (MMA educational prefix) |
| DeviceInfo manufacturer | midi2.diy |
Requires arm-none-eabi-gcc, a libDaisy checkout on branch feat/usb-midi2-transport (USB MIDI 2.0 descriptors Alt 0 + Alt 1, raw UMP RX/TX on MidiUsbTransport, STM32 HAL stack, no TinyUSB). MIDI2CPP_DIR defaults to ../...
make LIBDAISY_DIR=/path/to/libDaisyThe libDaisy core makefile defaults to gnu++14; this recipe overrides CPP_STANDARD to gnu++17 (midi2cpp floor). libdaisy.a must be prebuilt in the fork's build/.
Hold BOOT on the Daisy Seed, tap RESET to enter DFU, then:
make LIBDAISY_DIR=/path/to/libDaisy program-dfuWrites build/daisyseed-midi2.bin to internal flash at 0x08000000. The Daisy web programmer or dfu-util work too.
| Pin | Use |
|---|---|
| USB micro-B (onboard) | MIDI 2.0 device (only USB function, no CDC) |
| LED (onboard) | not wired |
Daisy Seed pinout and datasheet: https://electro-smith.com/products/daisy-seed.
lsusb | grep 0483:5740
amidi -l
PORT=$(amidi -l | grep -i 'Group 1' | awk '{print $2}')
timeout 7 amidi -p ${PORT} -d
ls /dev/snd/umpC*D0 # raw UMP endpointHardware validated 2026-05-28 on Linux ALSA: enumerates 0483:5740 as Daisy Seed MIDI 2.0, /dev/snd/umpC*D0 present, Group 1 visible to ALSA, the showcase voice messages confirmed via downscaled amidi capture (NoteOn/Off, CC 1 / CC 74, Pitch Bend, Channel Pressure, Program). Windows MIDI Services Console shows native data format Universal MIDI Packet, MIDI 2.0 Protocol = True.
Pair with the sibling host recipe daisyseed-host-midi2 on a second Daisy Seed: plug this device into the host's USB-A jack and the host decodes the full showcase stream over m2host.
Full UMP + MIDI-CI surface (Cortex-M7 @ 480 MHz, ample SRAM + SDRAM, in budget).
| UMP MT | Spec | Notes |
|---|---|---|
| 0x0 Utility | M2-104-UM §3 | JR heartbeat 500 ms |
| 0x4 MIDI 2.0 Channel Voice | M2-104-UM §7 | NoteOn/Off (16-bit vel), 32-bit CC, 32-bit Pitch Bend, 32-bit Channel Pressure, Program, Per-Note Pitch Bend, Registered Per-Note Controller |
| 0xD Flex Data | M2-104-UM §10 | Set Tempo (120 BPM), Set Time Signature (4/4) |
| 0x3 SysEx7 | M2-104-UM 7.7 | Universal Identity Reply, auto-fragmented |
| 0x5 SysEx8 + Mixed Data Set | M2-104-UM 7.8/7.10 | single stream id, single-chunk MDS |
| 0xF UMP Stream | M2-104-UM §11 | Endpoint Info, Device Identity, Endpoint Name, Product Instance ID, FB Info, FB Name |
MIDI-CI: Discovery + Endpoint Info, Profile GM 1, Property Exchange (DeviceInfo, ChannelList, ProgramList + built-in ResourceList) + Process Inquiry MIDI report, via the m2ci Appendix E convenience responder.
Always on while mounted: JR heartbeat (500 ms), UMP Stream + MIDI-CI Discovery responders, 1 Profile (GM 1), 4 PE resources (ResourceList, DeviceInfo, ChannelList, ProgramList).
Per cycle (~5 s):
| Scene | Content | MIDI 2.0 only because |
|---|---|---|
| A. Note | NoteOn 16-bit velocity 0xC000, 200 ms sustain, NoteOff |
16-bit velocity |
| B. Resolution | 32-bit CC 1 + CC 74, 32-bit Pitch Bend, 32-bit Channel Pressure | MIDI 1.0 caps at 7/14-bit |
| C. Program | Program Change 42 | |
| D. Per-Note | Per-Note Pitch Bend, Registered Per-Note Controller #7 (Volume) | Per-Note family is MIDI 2.0 only |
| E. Flex Data | Set Tempo (120 BPM), Set Time Signature (4/4) | MT 0xD |
demo_note walks C4 (60) to C5 (72) across cycles so each NoteOn is distinguishable on a logic analyzer. Captures live in monitor/.
MIT, inherits parent midi2cpp LICENSE. libDaisy is MIT (Electro-Smith).