🎛️
Square VCO
panel art
coming soon
coming soon
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Maddie MOD2
Square VCO
Oscillator
A V/oct square-wave oscillator with vibrato LFO and chiptune-style octave toggling.
- Width
- 4 HP
- Depth
- 28 mm
- Power
- +12V / −12V / +5V
- MCU
- Seeed XIAO RP2350
- Controls
- 3 pots · button · LED
- I/O
- 2 gate in · 1 CV in · PWM audio out
Overview
A square-wave oscillator with proper 1V/oct tracking via a 1024-entry lookup table. Tune it, pick one of six octaves, and add a sine-LFO vibrato. A chiptune mode rapidly toggles octaves at 20 Hz for that classic 8-bit warble.
Panel & I/O
| Control | Pin | Function |
|---|---|---|
| POT1 | A0 | Tune (1.0–2.0×) |
| POT2 | A1 | Octave select (1–6) |
| POT3 / CV | A2 | V/oct CV in (pitch) / vibrato level |
| IN1 | GPIO7 | In — Octave CV |
| IN2 | GPIO0 | In — Vibrato level CV |
| BUTTON | GPIO6 | Chiptune mode on/off |
| OUT | GPIO1 | Out — 10-bit PWM audio (~36.6 kHz) |
| LED | GPIO5 | Chiptune mode indicator |
Features
- 1V/oct tracking with a 1024-entry lookup table
- Six-step octave selection with CV
- Sine-LFO vibrato (up to ±5%)
- Chiptune mode — 20 Hz octave toggling
© 2026 Maddie Synths · original firmware CC0 1.0 · hardware design by Hagiwo