spi.py 文件源码

def transfer(tx_data):
    """Transfers data using the current SPI bus. Returns a list of bytes.

    tx_data: A list of bytes to send.

    Note: An exception is thrown if an error occurs during the transfer.
    """
    length = len(tx_data)
    tx_buffer = (ctypes.c_uint8 * length)(*tx_data)
    rx_buffer = (ctypes.c_uint8 * length)()
    ret = _LIB.spi_transfer(tx_buffer, rx_buffer, length)
    if ret < 0:
        raise Exception("spi transfer failed")
    return [rx_buffer[i] for i in range(length)]