qmk_firmware/keyboards/handwired/split65/promicro/info.json

{
    "matrix_pins": {
        "cols": ["F4", "F5", "F6", "F7", "B1", "B3", "B2", "B6"],
        "rows": ["D4", "C6", "D7", "E6", "B4"]
    },
    "diode_direction": "COL2ROW",
    "split": {
        "soft_serial_pin": "D3"
    },
    "processor": "atmega32u4",
    "bootloader": "caterina"
}