text5.c

51单片计算机中的定时器程序,在keil工程中编译

#include<reg51.h>
#include <intrins.h>
int mhz=0,tim=0,i=0; 		
sbit beep=P2^3;
int code table[]={5000,500,100,50,25,12,5};
int main()
{
	TMOD=0x11;
	TH0=(65536-100)/256;
	TL0=(65536-100)%256;
	TH1=(65536-50000)/256;
	TL1=(65536-50000)%256;
	EA=1;
	ET0=1;
	ET1=1;
	TR0=1;
	TR1=1;

	while(1);

	return 0;
}
void timer0() interrupt 1 
{
	TH0=(65536-100)/256;
	TL0=(65536-100)%256;
	mhz++;
	if(mhz==table[i])                //等一秒
		{

			beep=!beep;

		}
}
void timer1() interrupt 3  
{
	TH1=(65536-50000)/256;
	TL1=(65536-50000)%256;
	tim++;
	if(tim==6)                //等一秒
		{
			i=(i+1)%6;
		}

}