WHY2025 coprocessor firmware

Firmware for the CH32V203 coprocessor on the WHY2025 badge.

Features

• I2C slave device with interrupt
• Keyboard matrix scanning
• PWM control of display and keyboard backlights
• Controlling the ESP32-C6 radio (enable & boot pins)
• SD card detect & headphone detect
• Amplifier enable

To-do

• Real time clock functions