#include"at89x52.h"
#define uchar unsigned char
#define uint unsigned int
sbit m=P1^0;
void main()
{
TMOD=0X10; // T1为定时,方式1(不能自动重装载)
TR1=1; //开定时T1
m=1; //初值为高电平,可以不写
while(1) //死循环
{ TH1=(-5000)>>8; //16位定时器设置初值5ms
TL1=-5000;
while(TF1==0); //定时没有到,TF1==0则等待
{ TF1=0; //定时到,TF1==1清零
m=0; //输出低电平
TH1=(-12000)>>8; //T1设置初值12ms
TL1=-12000;
while(TF1==0); //定时没有到,则等待
{TF1=0;m=1;} //清零,同时输出高电平
}
}
}
[此贴子已经被作者于2008-8-18 11:10:43编辑过]
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