MIDI 1.0 / MIDI 2.0 UMP Universal MIDI Packet, Channel Voice 2.0, SysEx 7/8-bit Wire-Protocol Decoder & Byte Counter

UMP packets are fixed-length per message type (0x0/0x1/0x2: one 32-bit word; 0x3/0x4: two; 0x5/0xD/0xF: four; 0x6-0xE unassigned in UMP 1.1) with the type in the top nibble of byte 0. The MIDI 2.0 Channel Voice status table decodes 0x0/0x1 registered/assignable per-note controllers, 0x2/0x3 RPN/NRPN, 0x4/0x5 relative RPN/NRPN, 0x6 per-note pitch bend (32-bit), 0x8/0x9 Note Off/On (16-bit velocity + attribute type 1 = Pitch 7.9: 7-bit semitone + 9-bit fraction, 512 steps per semitone), 0xA poly pressure, 0xB control change, 0xC program change with bank-valid bit, 0xD channel pressure, 0xE channel pitch bend (32-bit, centre 0x80000000) and 0xF per-note management. SysEx7 packets are always 2 words carrying up to 6 data bytes; SysEx8 packets are always 4 words carrying a stream id plus up to 13 eight-bit-clean bytes. The MIDI 1.0 decoder honours the original specification: running status applies only to channel messages, System Real Time bytes may be interleaved anywhere without cancelling it, and System Common / SysEx cancel it. Field layouts are cross-checked against the Linux kernel, JUCE and cmidi2 implementations of the adopted UMP 1.1.2 specification.