qmk_firmware/keyboards/handwired/sono1/stm32f103/keyboard.json

{
    "usb": {
        "device_version": "0.0.1"
    },
    "matrix_pins": {
        "cols": ["A4", "A3", "B11", "B10", "B1", "B0", "A7", "A6"],
        "rows": ["A5", "B3", "A9", "A10", "B13", "B14", "B15", "A8", "B7", "B8", "B9", "C13", "A15", "A0", "A1"]
    },
    "diode_direction": "COL2ROW",
    "indicators": {
        "caps_lock": "B5",
        "num_lock": "B4",
        "kana": "A2",
        "on_state": 0
    },
    "development_board": "bluepill"
}