产生波形实验（DA转换）

要求：产生某种特定在波形

 1 /*DA转换实验 例如产生锯齿波*/
 2 
 3 #include <reg52.h>
 4 
 5 unsigned char xdata ad_cs0   _at_  0xc000;
 6 unsigned char xdata ad_cs1   _at_  0xc001 ;
 7 unsigned char xdata key_seg   _at_  0xd004;
 8 unsigned char xdata key_bit   _at_  0xd002;
 9 
10 sbit EOC=P3^2;
11 unsigned char disp_ram[6];
12 unsigned char seg7[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,
13                       0x77,0x7c,0x39,0x5e,0x79,0x71,0,0x80};
14 unsigned char scan[]={0x01,0x02,0x04,0x08,0x10,0x20};
15 
16 void delay()
17 {
18   unsigned char i,j;
19   for (i=0;i<200;i++)
20     for (j=0;j<2;j++);
21 }
22 
23 void main()
24 {
25    unsigned char i=0;
26    unsigned char ad_value;
27    unsigned char tmp,a;
28 
29 
30 
31     disp_ram[0]=17;
32     disp_ram[1]=16;
33     disp_ram[2]=16;
34     disp_ram[3]=16;
35     disp_ram[4]=16;
36     disp_ram[5]=16;
37 
38     ad_cs0=0;
39 
40     while(1)
41     {
42        key_bit=scan[i];
43        a=seg7[disp_ram[i]];
44        if (i==5)
45           a=a|0x80;
46        key_seg=a;
47        delay();
48        i++;
49        i=i%6  ;
50 
51        if (EOC)
52        {
53           ad_value=ad_cs0;
54           disp_ram[5]=ad_value*5/256;
55           tmp=(ad_value*5)%256;
56           disp_ram[4]=tmp/100;
57           disp_ram[3]=(tmp%100)/10;
58        }
59        ad_cs0=0;
60     } ;
61 
62 
63 }
DA转换 Code

 

posted @ 2013-05-22 08:36  蓬莱仙羽  阅读(774)  评论(0)  编辑  收藏  举报