#include<reg52.h>
#define uchar unsigned char
#define uint unsigned int
uchar shu=0,count=0;
uchar qian,bai,shi,ge;
long  f;
uchar code dutable[]={
0xc0,0xf9,0xa4,0xb0,0x99,
0x92,0x82,0xf8,0x80,0x90};

void display(uchar qian,uchar bai,uchar shi,uchar ge);
void int0() interrupt 0
{
 TR1=1;
 shu++;
  if(shu==16)//计15
   shu=0;
  TR1=0;
  EX0=0;
}
void t0() interrupt 3
{
 count++;
}
void init()
{
 TMOD=0x10;
 TH1=0;
 TL1=0;
 IE=1;
 ET1=1;
 EX0=1;
 IT1=1;
}
void delay(uint z)
{
 uint x,y;
 for(x=z;x>0;x--)
  for(y=110;y>0;y--);
} void main()
{ 
 init();
 while(1)
 {    
 
   
  f=(count*65536+TH1*256+TL1)/15;
  f=1000000/f;
   qian=f/1000; 
   bai=f%1000/100;
   shi=f%100/10;
   ge=f%10;
 
  display(qian,bai,shi,ge);
  count=0;
  TH1=0;
  TL1=0;
  TR1=1;
  EX0=1;
 }
}
void display(uchar qian,uchar bai,uchar shi,uchar ge)
{
   P2=0x01;
 P0=dutable[qian];
 delay(5);
 
 P2=0x02;
 P0=dutable[bai];
 delay(5);  P2=0x04;
 P0=dutable[shi];
 delay(5);  P2=0x08;
 P0=dutable[ge];
 delay(5); 
} 写的是低频率计，加信号时没反应．如果要两位小数的，如何改？？
此帖出自小平头技术问答