qmk_firmware/keyboards/handwired/onekey/stm32f405_feather/keyboard.json

{
    "keyboard_name": "Onekey Adafruit Feather STM32F405",
    "processor": "STM32F405",
    "bootloader": "stm32-dfu",
    "matrix_pins": {
        "cols": ["C2"],
        "rows": ["C3"]
    }
}