1 #include<reg51.h>
 2 
 3 
 4 #define unint unsigned int
 5 #define unchar unsigned char
 6 
 7 sbit k=P3^2;
 8 sbit L=P1^0;
 9 
10 unint a=1,b=1,c=1,d=1,s=0;
11 unchar code table[]={0xc0,0xf9,0xa4,0xb0,
12                         0x99,0x92,0x82,0xf8,
13                             0x80,0x90};
14 
15 
16 void
 
 delay(unint x)
17 {
18     unint i,j;
19     for(i=121;i>0;i--)
20         for(j=0;j<=x;j++);
21 }
22 
23 void main()
24 {
25        L=0;
26     P2=0x0f;
27     P0=table[0];
28     IT0=0;
29     EA=1;
30     EX0=1;
31     while(1);
32     
33 }
34 
35 void cut_num(void)
36 {
37     if(s==10000)
38         s=0
 
;
39     d=s%10;
40     c=(s/10)%10;
41     b=(s/100)%10;
42     a=(s/1000)%10;
43 }
44 void print_num()
45 {    
46     delay(1);
47     P2=0x08;
48     P0=table[d];
49     if((a!=0)||(b!=0)||(a==0&&b==0&&c!=0))
50     {
51         delay(1);
52         P2=0x04;
53         P0=table[c];
54     }
55     if(a!=0||(a==0
 
&&b!=0))
56     {
57         delay(1);
58         P2=0x02;
59         P0=table[b];
60     }
61     if(a!=0)
62     {
63         delay(1);
64         P2=0x01;
65         P0=table[a];
66     }
67 }
68 void int0()interrupt 0
69 {
70       
71         s++;
72         cut_num();
73         delay(300);
74         while(k==0)
75             print_num();
76         while(k!=0)
77             print_num();
78                 
79          
80     }

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