计数器

 #include <reg52.h>
 #define uint unsigned int 
 #define uchar unsigned char 
 uchar duan[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x83,0xc6,0xa1,0x86,0x8e,0x71,0x0e,0x0c,0x0b,0x07};
 //            0      1   2   3    4    5     6   7    8    9    A   B     C    D    E    F    1     2    3    4
 void delay(uint a)
 {
    while(a--);
 }
 
 main()
 {
 
    
    while(1)
    {
       
       P2=duan[0];
       delay(500000);
       P3=duan[18];
       P2=duan[1];
       delay(500000);
       P3=duan[18];
       P2=duan[2];
       delay(500000);
       P3=duan[18];
       P2=duan[3];
       delay(500000);
       P3=duan[18];
       P2=duan[4];
       delay(500000);
       P3=duan[18];
       P2=duan[5];
       delay(500000);
       P3=duan[18];
       P2=duan[6];
       delay(500000);
       P3=duan[18];
       P2=duan[7];
       delay(500000);
       P3=duan[18];
       P2=duan[8];
       delay(500000);
       P3=duan[18];
       P2=duan[9];
       delay(500000);
       P3=duan[18];
       P2=duan[10];
       delay(500000);
       P3=duan[18];
       P2=duan[11];
       delay(500000);
       P3=duan[18];
        P2=duan[0];
       delay(500000);
       P3=duan[18];
       P2=duan[1];
       delay(500000);
       P3=duan[19];
       P2=duan[2];
       delay(500000);
       P3=duan[19];
       P2=duan[3];
       delay(500000);
       P3=duan[19];
       P2=duan[4];
       delay(500000);
       P3=duan[19];
       P2=duan[5];
       delay(500000);
       P3=duan[19];
       P2=duan[6];
       delay(500000);
       P3=duan[19];
       P2=duan[7];
       delay(500000);
       P3=duan[19];
       P2=duan[8];
       delay(500000);
       P3=duan[19];
       P2=duan[9];
       delay(500000);
       P3=duan[19];
       P2=duan[10];
       delay(500000);
       P3=duan[19];
       P2=duan[11];
       delay(500000);
       P3=duan[19];
       
       
     }
    
  }
  /*smg(uint z,uint x);
    smg(0,17);
    delay(100000);
    smg(1,17);
    delay(100000);
     smg(2,17);
    delay(100000);*/