freq.h

来自「用C51写的单片机程序」· C头文件 代码 · 共 31 行

/*测频子程序*/
ulong fre;
bit T0flag=0;
uchar times=20,T1_carry=0;

void ini_time(void)
{TH0=0x3c;
 TL0=0xb0;
 TH1=0x00;
 TL1=0x00;
 times=20;
 T1_carry=0;
}

void service_t0() interrupt 1 using 2
{if(--times)  {TR0=0;TH0=0x3c;TL0=0xb0;TR0=1;}
 else
   {TR1=0;TR0=0;
    fre=T1_carry;
    fre<<=16;
    fre=fre+TH1*256+TL1;
    T0flag=1;
   }

}

void service_t1() interrupt 3 using 2
{T1_carry++;
}