Disqo

A wearable synthesizer — a smartwatch with three buttons, a high-resolution magnetic scroll wheel and a circular LCD display, designed for building a synth you can run on your wrist.

Hardware

Disqo is built around a custom PCB designed in KiCad.

Component	Description
ESP32-PICO-MINI-02	Espressif SiP with 8 MB flash and 2 MB PSRAM
GC9A01 round LCD	240×240 pixel 1.28" circular TFT display over SPI at 80 MHz
AS5600	12-bit magnetic rotary encoder over I2C — acts as a high-resolution scroll wheel (like a watch crown)
3 buttons	Physical inputs for navigation, selection and sleep/wake
Piezo buzzer	PWM-driven audio output (beep/boop, future synth capabilities)
MCP73831-2	Single-cell Li-Po battery charger via USB
32.768 kHz crystal	External RTC clock source for accurate timekeeping
Battery ADC	Monitors battery voltage

The PCB files, schematic, BOM and 3D models live in the pcb/ directory. An interactive HTML BOM is available at pcb/bom/ibom.html.

Firmware

The firmware runs on MicroPython with a patched gc9a01_mpy C module compiled in for fast display drawing.

Structure

firmware/
├── main.py              # Entry point — launches the watchface
├── boot.py              # MicroPython boot stub
├── apps/                # Applications (clock, main menu)
├── gui/                 # UI framework (menus, themes, text layout)
├── system/              # Hardware abstraction layer (HAL)
├── utils/               # Encoder math, datetime formatting, font helpers
├── fonts/               # Bitmap and TTF font definitions
├── scripts/             # Build, deploy and helper scripts
├── patches/             # Patches for gc9a01_mpy and MicroPython ESP32 port
└── typings/             # MicroPython type stubs for IDE support

Watchface

The current primary watchface features:

• DSEG7-style digital clock with "ghost" segments
• Greeting text that changes by time of day (Good morning / afternoon / evening)
• Battery icon with voltage display
• Date with day-of-week
• Double-buffered rendering with a textured background

Controls

• Rotary encoder (scroll wheel): Scrolls through menus and adjusts values
• Button 1 (B1): Wake from deep sleep; back/cancel in menus
• Button 3 (B3): Open main menu; select in menus
• B1 + B3 combo: Enter deep sleep

Apps

• Clock — Date, time, battery status, encoder angle
• Main Menu — Scrollable menu with items: date/time, alarm, theme, brightness, metronome, drone (sub-apps are still planned)

Building & Deploying

Prerequisites

• MicroPython source
• ESP-IDF toolchain
• esptool and mpremote

Compile MicroPython

The build script compiles MicroPython for the GENERIC_SPIRAM board with the patched gc9a01_mpy module:

cd firmware/scripts
./compile-micropython.sh

Patches are applied before building:

• gc9a01_mpy.patch — Faster display init, adds draw_len for text measurement
• micropython-ports-esp32.patch — Configures 80 MHz flash/SPIRAM, external RTC crystal, faster deep sleep wake

Deploy code to device

cd firmware/scripts
./copy-code.sh

This uses mpremote to copy the Python source files to the device and syncs the RTC to the host clock.

Set time

cd firmware/scripts
./set-time.sh

Future Plans

• Audio synthesis: Wrap pwm_audio for better piezo output, classic Bluetooth audio, digital audio synthesis libraries
• Sub-apps: Date/time setting, alarm, theme selector, brightness control, metronome, drone
• Smarter input polling and debouncing
• Theme persistence in non-volatile memory