矩阵按键

any_wind

电路图：


代码：

1. #include <REG52.h>
   
2. 
   
3. unsigned char code table[16]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};
   
4. 
   
5. sbit h1=P1^0;
   
6. sbit h2=P1^1;
   
7. sbit h3=P1^2;
   
8. sbit h4=P1^3;
   
9. sbit l1=P1^4;
   
10. sbit l2=P1^5;
    
11. sbit l3=P1^6;
    
12. sbit l4=P1^7;
    
13. 
    
14. void delay(int num)
    
15. {
    
16.     int i,j;
    
17.     for(i=0;i<num;i++)
    
18.         for(j=0;j<150;j++)
    
19.             ;
    
20. }
    
21. 
    
22. unsigned char scanfcode()
    
23. {
    
24.     unsigned char table_h[]={0xfe, 0xfd, 0xfb, 0xf7};
    
25.     unsigned char i;
    
26.     for(i=0;i<4;i++)
    
27.     {
    
28.         P1=table_h[i];
    
29.         if(l1==0)
    
30.             return i*4+0;
    
31.         else if(l2==0)
    
32.             return i*4+1;
    
33.         else if(l3==0)
    
34.             return i*4+2;
    
35.         else if(l4==0)
    
36.             return i*4+3;
    
37.     }
    
38. }
    
39. 
    
40. int main()
    
41. {
    
42.     P2=0X02;
    
43.     while(1)
    
44.     {
    
45.         P1=0XF0;
    
46.         if(P1!=0XF0)
    
47.         {
    
48.             delay(20);
    
49.             if(P1!=0XF0)
    
50.             {
    
51.                 P0=table[scanfcode()];    
    
52.             }
    
53.         }    
    
54.     }    
    
55. }