feat: Inline MIDI processing with expression and tuning CCs#111
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Replace deferred batch MIDI task with inline event processing in audio_handler. MIDI events are now handled on every audio DMA completion (every 256 samples), eliminating scheduling overhead and ensuring reliable delivery. Add support for: - CC7 (main volume, 0-127 → 0-10 range) - CC11 (expression, multiplies with volume) - Program Change (waveform selection) - CCs 36-43 (tuning parameters: bit rate, sample rate, formant, autotune, magnitude) Add waveform compensation (1.4× sine, 1.2× triangle, 1.0× square/saw) so waveform choice doesn't affect perceived volume. Applied pre-limiter to prevent DAC clipping.
enoragon
reviewed
Jul 8, 2026
| /// Sets expression from an incoming MIDI CC11 value (0-127). Multiplies with | ||
| /// `volume` for final output gain — see `handler::audio_handler`. | ||
| pub fn set_expression_from_midi(&mut self, value: u8) { | ||
| self.expression = value as i8; |
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what does the expression do? if it is just volume lets skip
| /// waveform. | ||
| pub fn set_waveform_from_midi(&mut self, channel: u8, program: u8) { | ||
| if channel == 9 || program > 2 { | ||
| return; |
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ignoring is fine for the channel but I think we should be mod wrapping for the programs over 2
| } | ||
| 36..=43 => { | ||
| shared.app_state_machine.lock(|msm| { | ||
| msm.set_tuning_from_cc(controller, value); |
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What is this, and why is it multiple? Let's just ignore the ccs we do not have. We should have one to cycle the musical key
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Replace deferred batch MIDI task with inline event processing in audio_handler. MIDI events are now handled on every audio DMA completion (every 256 samples), eliminating scheduling overhead and ensuring reliable delivery.
Add support for:
Add waveform compensation (1.4× sine, 1.2× triangle, 1.0× square/saw) so waveform choice doesn't affect perceived volume. Applied pre-limiter to prevent DAC clipping.