CozmikC1zzl3

C1ZZL3

Stable production firmware for the Cosmik C1ZZL3 Music Thing Modular Workshop Computer card.

C1ZZL3 is a dual phase-distortion synthesiser with custom Web MIDI envelopes, USB MIDI device/host support, optional Turing MIDI output, and a Turing machine mode with CV and pulse outputs.

For the user-facing card guide, see:

CARD_README.md

Stable Build

Current stable UF2:

uf2/C1ZZL3.uf2

Checksum:

6cb55940ab502cb38926d20f3cdd76e5f93909ebb391569d82ee385bb20fbf55

This is the hardware-tested 192 MHz RP2040 build promoted on 2026-06-25.

Previous UF2s are archived in:

uf2/archive/

Source snapshots and experiment notes are archived in:

archive/

Current Stable Feature Set

• Phase-distortion synth voice.
• Factory envelopes plus eight protected custom envelope slots.
• Web MIDI envelope editor.
• USB MIDI device mode for DAW/browser use.
• USB MIDI host mode for class-compliant controllers.
• MIDI notes with envelope triggering.
• MIDI CC control with knob pickup handoff.
• Turing machine audio, CV, pulse, and optional MIDI note output.
• Turing CV and pulse outputs continue running in synth mode.
• Settings readback from the card into the Web MIDI editor.
• Ring, noise, MIDI channel, Turing range, and Turing MIDI settings persist.

Controls

Switch middle: synth mode.

• Main: pitch
• X: phase distortion
• Y: waveform
• CV In 1: phase-distortion modulation
• CV In 2: waveform modulation
• Pulse In 2: envelope trigger and oscillator sync

Switch down from middle: performance edit and save.

• Main: oscillator 2 detune
• X: ring modulation
• Y: noise/grit

Switch up: Turing mode.

• Main: mutation/lock
• X: sequence length, 2 to 16 steps
• Y: internal clock speed
• Pulse In 1: external clock
• CV Out 1: stepped Turing CV
• CV Out 2: smoothed Turing CV
• Pulse Out 1/2: Turing pulses

MIDI

MIDI CC controls on the selected input channel:

• CC1: phase distortion
• CC20: oscillator 2 detune
• CC21: ring modulation
• CC22: noise amount
• CC23: waveform
• CC24: Turing CV octave range, from 1 to 8 octaves

The physical knobs and MIDI CC controls share the same control values. After a CC change, the related knob must be swept through the current value before it takes over again.

Web MIDI Editor

Hosted editor:

https://soveda.github.io/CozmikC1zzl3/web-midi/editor/

Local editor:

python3 -m http.server 5173 --directory web-midi/editor

Open:

http://localhost:5173

Use Chrome or another browser with Web MIDI and SysEx support.

How To Use The Editor

1. Pick a preset on the left, or add a custom one.
2. Choose Amplitude or Phase Distortion to focus on one lane at a time.
3. Drag points on the graph to change both level and timing.
4. Watch the point numbers. Matching numbers mean the stages are stacked at the same spot.
5. Use the tables below the graph for exact values when you want precise edits.
6. Use the action buttons on the right when you want to send, save, read, or export.

Button quick reference:

• Load RAM: send the envelope to the card until reset.
• Save Slot: store the selected custom envelope in flash.
• Delete Slot: clear the selected custom slot from card flash.
• Read Card: pull the current performance settings into the editor.
• Set Card: write the current performance settings to the card.
• Export JSON: download all editor presets.
• Reset Preset: restore the selected preset to its factory value.

The editor can save up to eight custom envelopes. Factory presets are not overwritten.

Build

cmake -S . -B build
cmake --build build

The built UF2 will be:

build/C1ZZL3.uf2

The stable production build currently reports:

FLASH: 133168 B
RAM: 141500 B

Stability Notes

This build is close to the practical processing limit of this RP2040 card format, so future changes should be tested carefully at maximum settings.

The stable version includes the lookup-table oscillator optimisation, 192 MHz clock, Turing MIDI output, settings readback, and full CC/knob pickup handoff. Tap tempo remains removed; Y is the Turing internal clock control.

Possible future optimisation notes are kept in:

FUTURE_NOTES.md

Repository Layout

• C1ZZL3.cpp: main firmware
• C1ZZL3_LUT.cpp / C1ZZL3_LUT.h: phase-distortion lookup tables
• FUTURE_NOTES.md: deferred optimisation and cleanup notes
• web-midi/editor/: browser editor
• uf2/C1ZZL3.uf2: current stable firmware
• uf2/archive/: older UF2s and rollbacks
• archive/: source snapshots and experiment notes
• CARD_README.md: user-facing card guide
• info.yaml: Workshop Computer site metadata

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