#pragma db code
#include<AT89X51.H>
#define uchar unsigned char
#define uint  unsigned int

sbit LED_0=P1^0;
sbit LED_1=P1^1;
sbit LED_2=P1^2;
sbit LED_3=P1^3;

/*=====0-9=====A-G=====*/
uchar a[16]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,
             0x80,0x90,0x88,0x83,0xc6,0x86,0x8e,0x82};
uchar one,two,three,four;

void delay(uint x);
void display(void);
void led_analyze(uint l);
void led_add();

void main()
{
  uint a,b;
  while(1)
  {
  for(a=0;a<100;a++)
   {
    display();
   }
   b++;
   led_analyze(b);
   if(b>9999) b=0;

  }
}

void delay(uint x)
{
  uint i;
  for(i=0;i<x;i++);
}  

void display(void)
{
  

  P0=a[one];
  LED_0=0;
  delay(100);
  LED_0=1;

  P0=a[two];
  LED_1=0;
  delay(100);
  LED_1=1;

  P0=a[three];
  LED_2=0;
  delay(100);
  LED_2=1;

  P0=a[four];
  LED_3=0;
  delay(100);
  LED_3=1; 
}

void led_analyze(uint l)
{
  l=l%10000;
  one=l/1000;
  two=(l/100)%10;
  three=(l%100)/10;
  four=(l%100)%10;
}