#! /usr/bin/env python

 #coding=utf-8

 import os

 import time

 from ctypes import *

 class USBI2C():

     ch341 = windll.LoadLibrary("CH341DLL.dll")

     def __init__(self, usb_dev = 0, i2c_dev = 0x5c):

         self.usb_id   = usb_dev

         self.dev_addr = i2c_dev

         if USBI2C.ch341.CH341OpenDevice(self.usb_id) != -1:

             USBI2C.ch341.CH341SetStream(self.usb_id, 0x82)

             USBI2C.ch341.CH341CloseDevice(self.usb_id)

         else:

             print("USB CH341 Open Failed!")

     def read(self, addr):

         if USBI2C.ch341.CH341OpenDevice(self.usb_id) != -1:

             obuf = (c_byte * 2)()

             ibuf = (c_byte * 1)()

             obuf[0] = self.dev_addr

             obuf[1] = addr

             USBI2C.ch341.CH341StreamI2C(self.usb_id, 2, obuf, 1, ibuf)

             USBI2C.ch341.CH341CloseDevice(self.usb_id)

             return ibuf[0] & 0xff

         else:

             print("USB CH341 Open Failed!")

             return 0

     def write(self, addr, dat):

         if USBI2C.ch341.CH341OpenDevice(self.usb_id) != -1:

             obuf = (c_byte * 3)()

             ibuf = (c_byte * 1)()

             obuf[0] = self.dev_addr

             obuf[1] = addr

             obuf[2] = dat & 0xff

             USBI2C.ch341.CH341StreamI2C(self.usb_id, 3, obuf, 0, ibuf)

             USBI2C.ch341.CH341CloseDevice(self.usb_id)

         else:

             print("USB CH341 Open Failed!")