stc89c51单片机定时器

chongdazds · 发表于 2013-11-28 15:42:23

//利用定时/计数器T1产生定时时钟,每隔10秒，发生一次声光报警
#include<reg52.h>
#define uchar unsigned char
uchar  temp,aa;
sbit  beep=P1^6;
sbit D1=P1^7;
void init()
{
   aa=0;
TMOD=0x10;
TH1=(65536-50000)/256;
TL1=(65536-50000)%256;
EA=1;
ET1=1;
TR1=1;
}
void main ()
{
init();
while(1)
{

      if(aa==10)
         {
         D1=0;
         beep=0;
         }
}
}
void timer1()  interrupt 3
{
   TH1=(65536-50000)/256;
TL1=(65536-50000)%256;
aa++;
D1=1;
beep=1;
}