import serial.rs485 import serial.serialutil import ctypes class RS485Ext(serial.rs485.RS485): def __init__(self, *args, **kwargs): super(RS485Ext, self).__init__(*args, **kwargs) self.writec = ctypes.cdll.LoadLibrary('writec.so') r = self.writec.init() def write(self, b): d = serial.serialutil.to_bytes(b) r = self.writec.writec(self.fileno(), d, len(d)) return r