qmk_firmware/keyboards/handwired/macroboard/f411/keyboard.json

{
    "usb": {
        "shared_endpoint": {
            "keyboard": true
        }
    },
    "matrix_pins": {
        "cols": ["B12", "B13", "B14", "B15", "A8", "A10"],
        "rows": ["A15", "B3", "B4", "B5", "B7"]
    },
    "diode_direction": "COL2ROW",
    "ws2812": {
        "driver": "pwm"
    },
    "processor": "STM32F411",
    "bootloader": "stm32-dfu",
    "features": {
        "bootmagic": true,
        "mousekey": true,
        "extrakey": true,
        "nkro": true,
        "rgblight": true,
        "audio": true
    },
    "board": "BLACKPILL_STM32_F411"
}