中断函数编写计时器

#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char
 
uchar code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};	 //数码管位选数据
sbit duan=P2^6;//段选信号,写数码管数据
sbit wei=P2^7;//位选信号,选择数码管
 
uint miao=0;		//秒
uint fen=0;			//分	   
uint n=0;			//计数
uint date[6]={0,0,0,0};	 
void delay(uint xms)			 //延时函数
{
     uint i,j;
	 for(i=xms;i>0;i--)
	  for(j=112;j>0;j--);
}
 
void write_address(uchar address)		 //写地址函数，选择数码管
{
    wei=1;
	P0=address;
	wei=0;
}
 
void write_date(uint n)				     //写数据函数，送入段选信号
{
     duan=1;
	 P0=table[n];
	 duan=0;
}										//显示函数
void display()
{	 	 
       write_date(date[0]);
      P0=0xff;
      write_address(0x7f);
       delay(1);
 
 
     write_date(date[1]);
	 P0=0xff;
	 write_address(0xbf);
	 delay(1);
 
	 write_date(date[2]);
	 P0=0xff;
	 write_address(0xef);
	 delay(1);
	 
 
	 write_date(date[3]);