python 控制USB继电器

1. 一般情况下，USB继电器通过上位机COM口发送HEX本文还采用这种方法控制命令

2. 控制命令通常由制造商提供。在这里，我以我手中的例子为例

废话少说 上代码

import logging import time  import serial from serial.tools import list_ports   class cmd:     ka1_on = bytes.fromhex('A00101A2')     ka1_off = bytes.fromhex('A00100A1')   class KACtrl(cmd):      def __enter__(self):         self.__get_KA()         self.serial = serial.Serial(self.com, 9600, bytesize=8, timeout=0.1)         if not self.serial.isOpen():             self.serial.open()         return self      def __get_KA(self):          for i in list_ports.comports():             if 'USB-SERIAL CH340' in i.description:  # 在设备管理器中 继电器串口的描述(唯一)                 self.com = i.name         logging.debug(f'KA port:{self.com}')      def __exit__(self, exc_type, exc_val, exc_tb):         self.serial.close()      def poweron(self):         self.serial.write(cmd.ka1_on)      def poweroff(self):         self.serial.write(cmd.ka1_off)   if __name__ == '__main__':     with KACtrl() as kac:         kac.poweron()         time.sleep(1)         kac.poweroff()