为防止单片机程序跑飞，常常利用看门狗来实现，如果没有及时喂狗，表示程序跑飞，就会重新运行单片机，proteus仿真。-Flew to prevent MCU program run, often use watchdog to realize, if there is no timely feed the dog, said the program run to fly, will rerun the single chip microcomputer, proteus simulation.