计算机系统有其自身的脆弱性,一旦程序计数器发生错误,就可能导致计算机陷入混乱,俗称“挂死”。克服“挂死”现象最有效的办法是采用计算机工作状态监视电路(简称COP监视电路)。COP监视电路的工作原理并不复杂,先选定单片机的一个I/O引脚,在主程序工作循环中使该引脚发出一个脉冲,当主程序正常工作时该脉冲就不断发出。COP监视电路监视该脉冲,一旦程序工作出现异常,脱离 Computer systems have their own vulnerability, once the program counter error, it may lead to computer confusion, commonly known as “hung up.” Overcome the “hanging dead” phenomenon is the most effective way to use computer operating status monitoring circuit (referred to as COP monitoring circuit). The working principle of the COP monitoring circuit is not complicated. First, select an I / O pin of the microcontroller to make a pulse to this pin in the main program working cycle. The pulse will be sent continuously when the main program is working normally. COP monitoring circuit monitors the pulse, once the program work abnormal, detachment