#include <reg52.h>

sbit k0=P1^0;

sbit k1=P1^1;

sbit k2=P1^2;

unsigned char second,minute,hour,i,k,l,j,x,y;

unsigned int n;

unsigned char code mod[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,

0x7f,0x6f};

timer0(void) interrupt 1

{

 n++;

 TH0=0x3c;

 TL0=0xb0;

 }

void delay()

{ unsigned int time,p;

  for(time=30;time>0;time--)

  for(p=0;p<10;p++);

}

void xianshi()

{

 if(n==20)

 {

  n=0;

  second++;

  while(second==60)

  { second=0;

    minute++;

if(minute==60)

{minute=0;

 hour++;

 if(hour==24)

 {

  hour=0;

  }}}}

 x=hour%10;

 y=hour/10;

 l=minute%10;

 j=minute/10;

 i=second%10;

 k=second/10;P0=0x00;

 P2=0x01;

 P0=mod[i];

 delay();P0=0x00;

 P2=0x02;

 P0=mod[k];

 delay();P0=0x00;

 P2=0x04;

 P0=0x40;

 delay();P0=0x00;

 P2=0x08;

 P0=mod[l];

 delay();P0=0x00;

 P2=0x10;

 P0=mod[j];

 delay();P0=0x00;

 P2=0x20;

 P0=0x40;

 delay();P0=0x00;

 P2=0x40;

 P0=mod[x];

 delay();P0=0x00;

 P2=0x80;

 P0=mod[y];

 delay();P0=0x00;

}

void kongzhi()

{if(k0==0)

 {TR0=0;

  while(k0==0) xianshi();

  delay();

  while(k0==1)

  {if(k1==0)

   {minute++;

    while(minute==60)

{minute=0;

}}

   while(k1==0) xianshi();

   if(k2==0)

   {minute--;

    while(minute==-1)

{minute=59;

}}

while(k2==0) xianshi();

xianshi();

}    

    if(k0==0)

{TR0=0;

 while(k0==0) xianshi();

 delay();

 while(k0==1)

 {if(k1==0)

  {hour++;

   while(hour==24)

   {hour=0;

   }}

  while(k1==0) xianshi();

  if(k2==0)

  {hour--;

   while(hour==-1)

   {hour=23;

   }}

   while(k2==0) xianshi();

   xianshi();

   }

if(k0==0)

{while(k0==0) xianshi();

 TR0=1;

 return;

 }}}}

void main()

{    

 TMOD=0x01;

 TH0=0x3c;

 TL0=0xb0;

 EA=1;

 ET0=1;

 TR0=1;

 while(1)

 {

  xianshi();

  kongzhi();

  }}