MIDI: parse the hardware port as a byte stream - #29
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The screenless pedal is meant to be programmed over either USB or its TRS Type-A MIDI ports, and the scene protocol now carries its schema, state and routing commands over SysEx. The transmit side learned all the USB-MIDI CIN lengths in commit db24ff6 ("Get the USB-MIDI code index numbers right in both directions"), but uart_midi_read() still treats F0-F7 as zero-length status bytes. A SysEx request arriving at the TRS input disappears before handle_midi_packet() sees it. The same reader recognizes only channel voice messages. It drops every real-time byte, so MIDI Clock arriving at the TRS jack never reaches USB, and System Common messages disappear too. A two-byte channel message also leaves the final packet byte holding data from an earlier three-byte event. Replace that ad-hoc reader with a byte-stream parser. Keep channel running status, emit real-time without disturbing a partly read message, handle System Common, and pack SysEx into the CIN 4..7 forms USB-MIDI needs. System Reset is the real-time exception and clears the parser state. Zero-pad every packet byte that the MIDI message does not use. Keep the parser next to the CIN helpers so the hardware MIDI path has host-side coverage. Feed it channel running status, real-time interleaved with both channel and SysEx messages, System Common, System Reset, and all three SysEx ending forms. Fixes: 95881ae ("Re-organize MIDI code a bit, add UART option") Assisted-by: Codex:gpt-5 Signed-off-by: diegoMalagrida <diegomalagrida@gmail.com>
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The screenless pedal can be programmed over either USB or TRS Type-A MIDI, and the current scene protocol carries schema, state, and routing commands over SysEx.
uart_midi_read()currently treats F0-F7 as zero-length status bytes, so a SysEx request arriving at the physical MIDI input is discarded beforehandle_midi_packet()sees it.The same reader drops every System Real-Time and System Common message. MIDI Clock arriving at the TRS jack therefore never reaches USB, and a two-byte channel message can retain the final byte of an earlier three-byte packet.
This replaces that ad-hoc reader with a byte-stream parser. It preserves channel running status, emits real-time without disturbing a partially received channel or SysEx message, handles System Common and System Reset, packs SysEx into CIN 4..7, and zero-pads unused packet bytes.
The host-side validation covers channel running status for two- and three-byte messages, real-time interleaved with channel and SysEx messages, System Reset, System Common, and all three SysEx ending forms. This revision is based on the reorganized tree and updates the validation include to
Firmware/midi/midi.h.Validated with:
make -BC Validation test-midi-cin && ./Validation/test-midi-cin(all MIDI checks pass)-Wall -Wextra -Wpedantic -Wconversionand AddressSanitizer/UBSan