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#include "reg52.h"
#include"intrins.h"
typedef unsigned int u16;
typedef unsigned char u8;
sbit beep=P1^5;
u8 flag=0;
void delay(u16 i)
{
while(i--);
}
void timer1()
{
TMOD|=0x10;
TH0=0XFC;
TL0=0X18;
ET0=1;
EA=1;
TR0=1;
}
void main()
{
timer1();
while(1)
{
if(flag==0)
{
beep=~beep;
delay(10);
}
}
}
void timer2() interrupt 1
{
static u16 a;
TH0=0XFC;
TL0=0X18;
a++;
if(a==60000)
{
flag=1;
a=0;
}
}
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