watchdog.c

S51单片机的watchdog看门狗演示程序

#include "reg51f.h"

void watchdog_reset(void)
	{
	 unsigned int newval;
	 newval=(CH<<8)|CL;
	 newval+=0xFF00;
	 CCAP4L=newval;
	 CCAP4H=newval>>8;
	}

void main(void)
	{
	 unsigned int i;
	 watchdog_reset();
	 CCAPM4=0x48;	   
	 CMOD=(CMOD&0x01)|0x40;		 // 构造PCA
	 CR=1;						 //开始PCA定时器，每0xFF00满即复位
	 for(i=0;i<1000;i++)
	 	watchdog_reset();
	}