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Changelog

All notable changes to midi2cpp are recorded here. Format follows Keep a Changelog and this project adheres to Semantic Versioning, mirrored from the upstream midi2 C99 policy.

[0.4.1]

TinyUSB upstream. Recipes that pulled the MIDI 2.0 driver from the sauloverissimo/tinyusb fork now pull from hathach/tinyusb at the merge commit of PR #3571. RX drain migrated from polling loop to the tud_midi2_rx_cb / tuh_midi2_rx_cb callbacks across 18 device, host, and bridge recipes. BUFSIZE aligned with upstream defaults (device without override = EPSIZE, host 512/512).

Changed

  • Examples: 15 recipes bumped TinyUSB pin to hathach/tinyusb upstream (PR #3571 merged 2026-05-19).
  • Examples: 3 ESP32-P4 recipes (esp32-p4-devkit-host-midi2, esp32-p4-devkit-bridge-midi2, esp32-p4-devkit-bridge2-midi2) bumped to the experiment/midi-coexistence branch on top of upstream master (alt-walk bcdMSC defer + opt-in user responder, staged as follow-up PRs).
  • Examples: RX drain moved from polling loops to driver callbacks (tud_midi2_rx_cb, tuh_midi2_rx_cb).
  • Examples: CFG_TUD_MIDI2_*_BUFSIZE overrides removed where the upstream default (= EPSIZE) is sufficient; host recipes aligned with the upstream midi2_host example (512/512).
  • README: Boards table reorganized; Status column renamed to Notes, per-row override badges removed. The Waveshare ESP32-P4-WIFI6-DEV-KIT is now listed as two rows: device-only (upstream, stable) and host / bridge (experimental branch).

Fixed

  • Examples: removed stale reference to the deprecated usbd_control.c source in the components/tinyusb/CMakeLists.txt of esp32-p4-devkit-bridge-midi2 and esp32-p4-devkit-bridge2-midi2 (the upstream merged usbd_control.c into usbd.c).
  • Examples: added default for CFG_TUD_MIDI2_USER_RESPONDER in the experimental branch so the opt-in macro compiles cleanly under -Werror=undef and -Werror=unused-function.

[0.4.0]

Track midi2 v0.4.0. Public Device / Host / Bridge APIs stay source-compatible where possible; sendFbInfo gains a uiHint argument to match the new spec field.

Changed

  • Depends on midi2 >= 0.4.0.
  • Device::sendFbInfo(...) gains uiHint between direction and firstGroup. Recipes must update their callsite.
  • FbInfoCb typedef gains uiHint between direction and firstGroup (recipes that wire onFbInfo directly must update).
  • Device::sendStreamConfigNotify(protocol) now auto-populates the JR_TX_ENABLE bit from the JR Heartbeat state. No API change.
  • Device::sendNoteOn / sendNoteOff no longer refuse attrData > 0xFF; the full 16-bit attribute_data round-trips through midi2 v0.4.0.
  • Device::sendTimeSignature gains an optional num32ndNotes parameter (default 8, SMF1 standard).
  • Device::sendJRClock / sendJRTimestamp keep the leading group argument; value is now ignored on the wire (MT 0x0 is Groupless).
  • Host::JrTimestampCb keeps (idx, group, ts); group is always 0.

[0.3.1]

ESP Component Registry support. midi2cpp now ships an idf_component.yml at the root and an if(ESP_PLATFORM) gate in CMakeLists.txt, so ESP-IDF projects can pull it through the official Espressif registry with semver constraints instead of hard-pinning a git tag.

Added

  • idf_component.yml at the repo root (description, version, url, license, maintainers, tags, and dependencies.sauloverissimo/midi2
  • ESP-IDF gate at the top of CMakeLists.txt: when ESP_PLATFORM is set, calls idf_component_register(SRCS src/midi2_*.cpp INCLUDE_DIRS src REQUIRES midi2) with cxx_std_17 and returns before project() runs. Native CMake consumers (Pico SDK, vcpkg, FetchContent, system installs) are unaffected by the gate.

Install (ESP-IDF, new)

# main/idf_component.yml
dependencies:
  sauloverissimo/midi2cpp: ">=0.3.1"

The Component Manager pulls midi2cpp from the registry; midi2 is resolved transitively (declared in midi2cpp's own idf_component.yml).

[0.3.0]

Renamed from midi2_cpp to midi2cpp in deference to starfishmod/MIDI2_CPP (maintained since 2021 by Andrew Mee, MIDI Association TSB Rep), which operates in the same domain. Keeping the namespaces disjoint avoids confusion in package managers and search.

This is a breaking rename. Every consumer-facing identifier moved:

Breaking

  • Repository: github.com/sauloverissimo/midi2_cpp -> github.com/sauloverissimo/midi2cpp (the old URL redirects on the GitHub side, but new code should pin the new name).
  • Header: <midi2_cpp.h> -> <midi2cpp.h>. using namespace midi2; is unchanged; the C++ API surface (m2device, m2host, m2bridge, m2ci, Bridge, Device, ...) is unchanged.
  • CMake target: midi2_cpp -> midi2cpp; alias midi2_cpp::midi2_cpp -> midi2cpp::midi2cpp. target_link_libraries(... midi2cpp) replaces ... midi2_cpp.
  • Preprocessor macros: MIDI2_CPP_* -> MIDI2CPP_* (MIDI2CPP_BUILD_TESTS, MIDI2CPP_MAX_PROFILES, MIDI2CPP_MAX_PROPERTIES, MIDI2CPP_MAX_SUBSCRIBERS, MIDI2CPP_HOST_MAX_DEVICES, MIDI2CPP_BRIDGE_MAX_SLOTS).
  • Manifests: library.properties name=midi2cpp, library.json "name": "midi2cpp". The Arduino Library Manager and the PlatformIO Registry treat the rename as a new entry; the previous midi2_cpp listings will be retired in a follow-up PR to arduino/library-registry.

Changed

  • Dependency on midi2 bumped to v0.3.4 across every install path (Arduino LM depends=midi2 (>=0.3.4), PlatformIO ^0.3.4, ESP-IDF version: "v0.3.4", CMake find_package(midi2 0.3.4 CONFIG) + FetchContent_Declare(... GIT_TAG v0.3.4)). midi2 v0.3.4 fixes the ESP-IDF Component Manager gate (dist/ filtered from the dependency tarball); without it, ESP-IDF recipes failed configure.

Migration

-#include <midi2_cpp.h>
+#include <midi2cpp.h>

CMake:

-FetchContent_Declare(midi2_cpp ...)
-target_link_libraries(my_target PRIVATE midi2_cpp)
+FetchContent_Declare(midi2cpp ...)
+target_link_libraries(my_target PRIVATE midi2cpp)

Arduino Library Manager: search midi2cpp (the previous midi2_cpp entry will be removed once the registry PR lands).

PlatformIO: lib_deps = sauloverissimo/midi2cpp @ ^0.3.0.

[0.2.0]

Single source of truth for the MIDI 2.0 stack: midi2cpp no longer vendors the C99 core and is published as a regular Arduino / PlatformIO library that depends on midi2 explicitly. Every recipe under examples/ was migrated to pull midi2 externally through the build system that fits its host (FetchContent for Pico SDK + TinyUSB native CMake, IDF Component Manager for ESP-IDF, lib_deps for PlatformIO).

This is a breaking release. Consumers that previously vendored midi2cpp/src/midi2.{h,c} directly will break; the migration path is documented in the manifest below and in the per-build-system patterns shipped under examples/.

Breaking

  • Vendored src/midi2.{h,c} removed. midi2cpp now declares midi2 as an external dependency:
    • library.properties carries depends=midi2 (>=0.3.4). Arduino Library Manager auto-installs midi2 when a sketch includes midi2cpp.
    • library.json carries dependencies."sauloverissimo/midi2": "^0.3.4". PlatformIO resolves midi2 from its registry.
    • The root CMakeLists.txt exposes a three-layer fallback at the top (if(NOT TARGET midi2) -> find_package(midi2 0.3.4 CONFIG) -> FetchContent_Declare(midi2 GIT_TAG v0.3.4)), then links midi2cpp PUBLIC midi2::midi2 so downstream targets see the C99 core transitively.

Added

  • midi2::Bridge (alias m2bridge): composes Device + CI + Host with a multi-Function-Block topology, a per-slot group rewrite window, dynamic FB names sourced from upstream Endpoint Names, and a USB-MIDI 1.0 byte-stream uplift path (feedHostMidi1Bytes) for legacy upstream devices that arrive on alt 0. Slot lifecycle via slotSetActive(idx, active, alt). Reusable across bridge recipes; the multi-FB Stream Discovery responder lives inside the class so each new bridge recipe gets it for free.
  • tests/test_midi2_bridge.cpp: 11 host-side sub-tests covering m2bridge construct/destruct heap balance (50x cycle stress), topology setter bounds and post-begin() lock, group rewrite formula on slots 0/1/3, out-of-range slot rejection, and the USB-MIDI 1.0 byte-stream uplift path. Compiles and runs clean under -fsanitize=address,undefined.
  • architecture.png referenced from the README, replacing the previous inline ASCII layer diagram.
  • CMake entry surface for downstream consumers: the root CMakeLists.txt follows the same find_package -> FetchContent fallback pattern that midi2 itself ships. Subprojects pulling midi2cpp via add_subdirectory or FetchContent skip the find_package step (if(NOT TARGET midi2) guard).

Changed

  • README tagline drops the zero-allocation claim. midi2cpp allocates in two narrow places (m2bridge::begin() slot tables and std::function callback storage), so the wrapper is now described as static-by-default. The C99 core (midi2) remains strictly zero-allocation. Same shift applied to the logo.
  • README "Manual vendor" path rewritten: pre-v0.2 builds vendored a single midi2cpp/src/midi2.{h,c} copy; today the consumer downloads both repositories side by side and adds midi2/dist/ plus midi2cpp/src/ to its include path.
  • paragraph in library.properties rewritten: drops comparisons with other libraries, focuses on what midi2cpp itself ships and the embedded targets validated.

Examples / Recipes

Migrated to depend on midi2 externally (all 20 recipes)

Build system Mechanism Recipes
Pico SDK FetchContent_Declare(midi2 GIT_TAG v0.3.4) plus target_link_libraries(midi2cpp PUBLIC midi2::midi2) rp2040-midi2, waveshare-rp2040-midi2, sparkfun-promicro-rp2350-midi2, waveshare-rp2350-usb-a-midi2, waveshare-rp2350-usb-a-bridge-midi2, adafruit-feather-rp2040-host-midi2, adafruit-feather-rp2040-bridge-midi2, rp2040-promicro-ump-test-bench
TinyUSB native CMake same FetchContent pattern as Pico SDK xiao-samd21-midi2, nrf52840-promicro-midi2
ESP-IDF idf_component.yml declares midi2: { git: ..., version: ">=0.3.4" } and idf_component_register lists midi2 in REQUIRES arduino-nano-esp32-midi2, esp32-s3-devkitc-usb-midi2, esp32-p4-devkit-usb-midi2, esp32-p4-devkit-host-midi2, esp32-p4-devkit-bridge-midi2, esp32-p4-devkit-bridge2-midi2, t-display-s3-midi2
PlatformIO + ESP32_Host_MIDI lib_deps += sauloverissimo/midi2 @ ^0.3.4 esp32-c6-devkitc-multi-midi2, esp32-s3-devkitc-host-midi2, t-display-s3-shield-host-midi2

Each recipe drops the ${MIDI2CPP_ROOT}/src/midi2.c (or midi2_c99 helper library) from its source list. Other midi2cpp sources (midi2_device.cpp, midi2_ci.cpp, midi2_host.cpp, midi2_bridge.cpp) keep being compiled inline from the parent tree via ${MIDI2CPP_ROOT}/src until the host helper-library shape is finalised in a future cycle.

New recipes since v0.1.0

  • arduino-nano-esp32-midi2, Arduino Nano ESP32 (ESP32-S3-MINI-1, PID 0x4093). Full Showcase mirroring esp32-s3-devkitc-usb-midi2; single GPIO LED on D13 / GPIO48 instead of WS2812.
  • xiao-samd21-midi2, Seeed Studio XIAO SAMD21 (ATSAMD21G18A, PID 0x40F0). Tier C minimal core; first recipe to use the TinyUSB native CMake build system path. Hardware validated: ALSA Group 1 (Main), chromatic walk + 32-bit CC #74 sweep streaming. Final size: text 34884 / 256K flash (13%), bss 9832 / 32K SRAM (30%).
  • nrf52840-promicro-midi2, nRF52840 Pro Micro / Nice!Nano class (PID 0x40F1). Tier B subset: Per-Note Pitch Bend vibrato + chromatic walk + RPN / NRPN / RelRPN / RelNRPN burst. Same TinyUSB native CMake build path as the SAMD21 recipe. Hardware validated on Nice!Nano. Final size: text 38832 / 1 MB flash (3.7%), bss 2526 / 256 KB SRAM (1%).
  • esp32-p4-devkit-bridge2-midi2, ESP32-P4 dual-stack bridge (PID 0x4095) built on top of m2bridge. Carries the same multi-FB topology as esp32-p4-devkit-bridge-midi2 but consumes the reusable Bridge class instead of an inline slot table + Stream Discovery responder.

[0.1.0]

First public release. C++17 Arduino-style wrapper for MIDI 2.0 on embedded devices, layered over the portable midi2 C99 library (vendored stb-style at src/midi2.{h,c} from v0.3.0+).

midi2::Device — UMP transport (M2-104)

  • Lifecycle: begin() initialises the dispatcher and proc; the caller owns the platform USB stack lifecycle. task() runs the JR Timestamp heartbeat. isMounted(), altSetting() accessors.
  • All 8 message types covered:
    • MT 0x0 Utility: sendNoop, sendJRClock, sendJRTimestamp, sendDctpq, sendDeltaClockstamp. Defensive heartbeat via enableJRHeartbeat(intervalMs) (default 500 ms).
    • MT 0x1 System (10 wrappers + generic escape): tune request, clock, start/continue/stop, active sensing, system reset, MTC, song select, song position, plus sendSystemGeneric.
    • MT 0x2 MIDI 1.0 CV (7 wrappers + ByteStreamConverter): note on/off, CC, program, pitch bend, channel pressure, poly pressure. Inbound MT 0x2 can be auto-upscaled to MT 0x4 callbacks via setUpscaleMt2(true).
    • MT 0x3 SysEx7: sendSysEx7(group, data, len) with automatic fragmentation; reassembly via onSysEx7 (512 byte buffer).
    • MT 0x4 MIDI 2.0 CV (15 wrappers): note on/off (with attribute type+data), CC, program (with optional bank), pitch bend, channel pressure, poly pressure, RPN, NRPN, Relative RPN/NRPN, per-note pitch bend, registered/assignable per-note controllers, per-note management.
    • MT 0x5 SysEx8: sendSysEx8(group, streamId, data, len) with automatic fragmentation; reassembly via onSysEx8.
    • MT 0xD Flex Data (6 wrappers): tempo, time signature, metronome, key signature, sendChordName(ChordDescriptor) (20-field struct), flex text (refuses payloads > 12 bytes; multi-UMP fragmentation deferred).
    • MT 0xF UMP Stream (6 wrappers): device identity (mfrId[3] MSB-first), endpoint name update, product instance ID update, FB name update, start/end of clip (endpoint-wide, no group field).
  • 49 inbound dispatch callbacks via onXxx(std::function) setters.
  • All sendXxx return bool: true = emitted, false = dropped on back-pressure or refused at API boundary.
  • Bit Scaling (M2-115): scaleUp7to16, scaleUp7to32, scaleUp14to32, scaleDown16to7, scaleDown32to7, scaleDown32to14 static methods, exhaustive roundtrip tested.
  • Helpers: setUmpGroup, setGroupRemap, downgradeMt4ToMt2, cableEventToUmp, setUpscaleMt2.
  • ByteStreamConverter inner class: MIDI 1.0 DIN-5 byte stream → UMP MT 0x2 / MT 0x3 with running status and SysEx accumulation.

midi2::CI — MIDI-CI v1.2 (M2-101)

  • Lifecycle: begin(mfrId[3], family, model, version, ciCat=0x1C) enables Profile + PE + PI by default.
  • MUID: muid(), regenerateMuid(). Auto-regeneration on collision and on Invalidate MUID via the caller-supplied RNG (CI::setRngFn).
  • Convenience responder (M2-101 Appendix E) auto-replies to Discovery, Profile Inquiry, PE Capability, PE Get; opt-out via setting custom callbacks. NAK-on-unknown enabled by default.
  • Discovery: sendDiscoveryInquiry() (Initiator), onDiscovery / onDiscoveryReply notifications, onInvalidateMuid.
  • Profile (M2-101 §7): addProfile, removeProfile, callbacks for onProfileInquiry, onProfileEnable, onProfileDisable, onProfileAdded, onProfileRemoved, onProfileDetailsInquiry, onProfileSpecificData. Storage tunable via MIDI2CPP_MAX_PROFILES (default 8).
  • Property Exchange (M2-101 §8, M2-103, M2-105):
    • Registry: addProperty(name, getter, setter=nullptr) (read-only by default), addPropertyStatic(name, value), removeProperty. Storage tunable via MIDI2CPP_MAX_PROPERTIES (default 8).
    • Subscribe / Notify state machine: setPropertySubscribable(name, true), notifyPropertyChanged(name) for fan-out, subscriberCount(). Subscriber registry tunable via MIDI2CPP_MAX_SUBSCRIBERS (default 4).
    • PE callbacks deliver raw bytes (header + body) instead of NUL-terminated strings, to avoid silent truncation of large JSON payloads.
  • Process Inquiry (M2-101 §9 + Appendix F): setMidiReport, onPICapability, onMidiReportInquiry.

midi2::Host — USB MIDI 2.0 host shape

  • Reactive multi-device host (MIDI2CPP_HOST_MAX_DEVICES, default 4). Caller wires tuh_midi2_* (or platform-equivalent) into notifyDeviceMounted/Unmounted, feedRx(idx, words, count) and setWriteFn(idx, words, count).
  • Per-device DeviceIdentity populated as UMP Stream Endpoint Discovery + MIDI-CI Discovery replies arrive: umpVerMajor/Minor, supportsMidi1Protocol, supportsMidi2Protocol, numFunctionBlocks, manufacturerId[3], familyId, modelId, version, endpointName, productInstanceId, bcdMSC, altSettingActive, ciMuid, ciDiscoveryPending / ciDiscoveryRequestId / ciDiscoverySentMs for Initiator timeout tracking.
  • CI Initiator role: host owns its own MUID (seeded via setRngFn, regeneratable on collision), sends Discovery Inquiry, matches replies by request id.
  • Auto-discovery on mount (default ON): UMP Stream Endpoint Discovery
    • MIDI-CI Discovery Inquiry fire automatically when notifyDeviceMounted is called.
  • 22 inbound dispatch callbacks, all idx-prefixed (NoteOn/Off, CC, Pitch Bend, Channel/Poly Pressure, Per-Note Pitch Bend, Per-Note controllers, Program, SysEx7/8, Flex Data, JR Timestamp, plus identity-update lifecycle).
  • Group remap per device: setInboundGroupRemap(idx, map[16]) for the bridge use case downstream of a multi-group endpoint.
  • Threading model documented: feedRx and notifyDeviceMounted/Unmounted are task-context only; ISR-context platforms must defer via their own queue.

Bridge & internals

  • Device ↔ CI bridge via friend-only methods (_setCiSysExHook, _ciWriteFnContext); user-facing onSysEx7 keeps working alongside CI's SysEx routing.
  • Two-hop dispatch context (proc.context = &dispatch, dispatch.context = DeviceState*) lets midi2_dispatch_feed and reassembled SysEx callbacks coexist without upstream patches.
  • ~CI() clears Device's CI hook to avoid use-after-free if CI dies before Device.
  • removeProperty mirrors midi2_ci's left-shift on the parallel pe_getters[] / pe_setters[] arrays (alignment invariant).

Platform contract (5 caller-wired hooks)

  • Device::setWriteFn(WriteFn) — outbound UMP. Library invokes the caller's function for every sendXxx and the JR heartbeat.
  • Device::feedRx(const uint32_t* words, size_t count) — inbound UMP. Caller pumps RX into the library; chunks transparently to the upstream uint8_t word_count limit of midi2_proc_feed.
  • Device::setNowFn(NowFn) — monotonic ms clock for the JR heartbeat. When unset, the heartbeat never fires (link-safe on bare hosts).
  • Device::setMounted(bool) / Device::setAltSetting(uint8_t) — caller informs USB enumeration state.
  • CI::setRngFn(RngFn) — caller-supplied entropy source. When unset, MUID stays at the value seeded in begin().

Host follows the same pattern with idx-prefixed equivalents (Host::setWriteFn, feedRx(idx, …), notifyDeviceMounted(idx, …), notifyDeviceUnmounted(idx), setNowFn, setRngFn).

Platform-agnostic library

  • Removed every #if defined(ARDUINO) || defined(PICO_PLATFORM) || defined(ESP_PLATFORM) block from midi2_device.{h,cpp} and the platform-conditional RNG #if chain from midi2_ci.cpp. The library no longer pulls <Arduino.h>, pico/time.h, esp_timer.h, or any USB stack header.
  • Removed the MIDI2CPP_TEST_MODE build option. Tests now consume the same public hooks platforms wire. One contract, one code path.
  • Device::begin() no longer claims to call tusb_init internally. It initialises the library's own dispatcher and returns; the caller owns the platform USB stack lifecycle.
  • Device::task() drops the commented tud_task stubs.
  • C++17 floor enforced via static_assert(__cplusplus >= 201703L) in midi2cpp.h.
  • lib/tinyusb git submodule and the .gitmodules entry removed. The library has zero external dependencies: midi2 C99 stays vendored, every USB stack and clock and RNG source is caller-wired. git clone is the install — no --recurse-submodules, no half-initialised state.

Examples / Recipes

12 platform recipes covering RP2040, RP2350, ESP32-S3 and ESP32-P4 boards, each with the platform-specific glue + a showcase main:

  • rp2040-midi2 — Raspberry Pi Pico, first concrete platform recipe
  • waveshare-rp2040-midi2 — Waveshare RP2040 Pi Zero
  • sparkfun-promicro-rp2350-midi2 — SparkFun Pro Micro RP2350
  • ump-test-bench-rp2040 — RP2040 Pro Micro (Tenstar Robot), deterministic 101-entry UMP catalog emitter for Windows MIDI Services consumer-side testing
  • esp32-s3-devkitc-usb-midi2 — ESP32-S3 DevKitC-1 (PID 0x4090)
  • esp32-p4-devkit-usb-midi2 — Waveshare ESP32-P4-WIFI6-DEV-KIT device (PID 0x4091, INT PHY OTG_FS, mandatory LP_SYS.usb_ctrl swap)
  • esp32-p4-devkit-host-midi2 — same kit as host (UTMI PHY OTG_HS)
  • esp32-p4-devkit-bridge-midi2 — same kit as dual-stack bridge (PID 0x4092), validated with simultaneous MIDI 1.0 (Arturia MiniLab 25) + MIDI 2.0 (ESP32-S3) host coexistence via the experimental TinyUSB alt-walk bcdMSC defer
  • adafruit-feather-rp2040-host-midi2 — Adafruit Feather RP2040 USB Host with SSD1306 OLED, MIDI 2.0 host over PIO-USB
  • adafruit-feather-rp2040-bridge-midi2 — same Feather as dual-stack bridge (USB-C device + USB-A host)
  • waveshare-rp2350-usb-a-midi2 — Waveshare RP2350-USB-A device (requires R13 hardware mod)
  • waveshare-rp2350-usb-a-bridge-midi2 — same kit as dual-stack bridge

Each recipe ships with: TinyUSB PR #3571 fork bootstrap script (ESP-IDF recipes use idf/scripts/fetch_tinyusb.sh; Pico SDK recipes use CMake FetchContent), USB descriptors with PID, board-specific platform glue, and a README with build, flash and validation instructions.

Build, packaging, tests

  • Triple build: Arduino library.properties, PlatformIO library.json, CMake.
  • midi2 C99 v0.3.0 vendored stb-style at src/midi2.{h,c}.
  • 6 host-side test binaries (test_midi2_device, test_midi2_ci, test_midi2_host, test_midi2_conversion, test_midi2_flex, test_midi2_scaling) with 70+ assertions, all green under -Wall -Wextra -Wpedantic on gcc + clang.
  • GitHub Actions: host-tests matrix (Ubuntu / macOS), Pico SDK example build, Arduino compile guarded by .ino presence.

Documentation

  • README with quickstart, four-hooks contract, Boards table covering the 12 recipes plus other reference platforms (Teensy core fork as direct consumer), Architecture diagram of the 4-layer stack, Three-shapes table (m2device / m2host / m2bridge planned), Install paths for Arduino IDE / PlatformIO / ESP-IDF / CMake FetchContent / git submodule / manual vendor.
  • Override status badges on Boards table rows: override (blueviolet) for unmerged-PR/fork dependencies, experimental (yellow) for research branches on top of an override.

Known limitations

  • AVR Uno (2 KB RAM) is out of scope.
  • setMaxSysexSize not exposed (midi2 C99 lacks the setter upstream).
  • 5 Initiator-role senders (sendEndpointInfoInquiry/Reply, sendAck, sendProfileDetailsReply, sendProfileSpecificData) deferred — the convenience responder covers the common Receiver flows.
  • sendFlexText does not yet fragment payloads > 12 bytes.
  • MT 0x2 named senders cover the simple case; UMP → DIN-5 byte stream bridge deferred.
  • m2bridge reusable class (composition of host + device with an UMP router) is the headline target for the v0.2 cycle; today the bridge pattern lives per-recipe in the three bridge examples.