#include<reg51.h>
#define uchar unsigned char
#define uint unsigned int
uchar
    led[17]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e,0xff};
void main()
{   uchar i,temp;
    uint lp;
    while(1)
    {
    P1=0xf0;
    if((P1&0xf0)!=0xf0);
    {
      for(i=0;i<4;i++)
      {   P1=~(1<<i);
           if((P1&0xf0)!=0xf0)
           {    temp=P1&0xf0+i;
                  break;
                  }
                  }
                  }
          switch(temp)
          {
              case 0xe0:P0=led[0];break; 
              case 0xd0:P0=led[1];break;             
              case 0xb0:P0=led[2];break; 
              case 0x70:P0=led[3];break;
              case 0xe1:P0=led[4];break; 
              case 0xd1:P0=led[5];break; 
              case 0xb1:P0=led[6];break;
              case 0x71:P0=led[7];break;
              case 0xe2:P0=led[8];break;
              case 0xd2:P0=led[9];break;
              case 0xb2:P0=led[10];break; 
              case 0x72:P0=led[11];break;
              case 0xe3:P0=led[12];break;  
              case 0xd3:P0=led[13];break;
              case 0xb3:P0=led[14];break; 
              case 0x73:P0=led[15];break;
              default:P0=led[0];      
              }
              }
              for(lp=1;lp<15000;lp++);
              }
              
#include<reg51.h>
#define uchar unsigned char
#define uint unsigned int
sbit key=P1^7;
void main()
{
    uint lp;
    uchar count;
    count=0;
    while(1)
    {
      if(key==0)count++;
       if(count==16)count=0;
          P1=~count;
           for(lp=1;lp<1500;lp++);
     }
}