配置PCA的一点总结12单片机

先看代码

#include "stc12.h"

unsigned int Last_Capture_Data=0; 
unsigned int New_Capture_Data=0;  
unsigned int g_Period=0;      
unsigned int g_Frequency=0;  
unsigned char str1[12];
unsigned char str2[12]; 
bit Capture_over = 0;


sbit KEY_1 = P2^7;

extern void InitLcd1602();
extern void LcdShowStr(unsigned char x, unsigned char y, unsigned char *str);

void Delay50ms();
void PCA_Init (bit module);
void IntToString(unsigned char *str, unsigned int dat);

void main (void)
{
    PCA_Init(0);
    InitLcd1602();
    P2 = 0xF7;

    while(1)
    {
        if(!KEY_1)
        {
            Delay50ms();
            if(!KEY_1)      
            {
                while(!KEY_1);
                CCAPM0 = 0x11;
                CR = 1;
            }
        }

        if(Capture_over)
        {
            Capture_over = 0;
//                           g_Frequency = (long)1000000 / g_Period; 
            g_Frequency = (long)11059200 / (g_Period * 12);

            IntToString(str1, g_Period);
            IntToString(str2, g_Frequency);
            LcdShowStr(1, 0, "length:");
            LcdShowStr(8, 0, str1);
            LcdShowStr(1, 1, "freque:");
            LcdShowStr(8, 1, str2);

        }
    }
}


void PCA_Init (bit module)
{
    //CIDL    -       -       -       CPS2    CPS1    CPS0    ECF
    CMOD = 0x80;

    //CF      CR      -       -       -       -       CCF1    CCF0
    CCON = 0x00;

    if (module == 0)                
    {
        CCAPM0 = 0x10;
        CCAP0L = 0x00;
        CCAP0H = 0x00;
    }
    else                                 
    {
        CCAPM1 = 0x11;
        CCAP1L = 0x00;
        CCAP1H = 0x00;
    }


    CL = 0x00;                
    CH = 0x00;

    EA = 1;

    //CR = 1;                     
}

void IntToString(unsigned char *str, unsigned int dat)
{
    unsigned char buf[12];
    unsigned char i = 0;
    do{
        buf[i++] = dat % 10;
        dat /= 10; 
    }while(dat > 0);

    while(i-- > 0)
    {
        *str++ = buf[i] + '0';//数组转换成ASCII反向拷贝到字符串指针
    }
    *str = '\0';
}

void PCA_Int(void) interrupt 7
{
    if (CCF0)                   
    {
        CCF0 = 0; 
        if(Last_Capture_Data == 0)
        {
              Last_Capture_Data = CCAP0H; 

              Last_Capture_Data = (Last_Capture_Data << 8) + CCAP0L; 
        }
        else 
        {            
            New_Capture_Data = CCAP0H;         

            New_Capture_Data = (New_Capture_Data << 8) + CCAP0L;
            g_Period = New_Capture_Data - Last_Capture_Data;
            CR = 0;
            CCAPM0 = 0x10;

            Last_Capture_Data=0;  
            CCAP0L = 0x00;
            CCAP0H = 0x00;
            CL = 0x00;                 
            CH = 0x00;

            Capture_over = 1;
        }
    }

}

void Delay50ms()        //@11.0592MHz
{
    unsigned char i, j, k;

    i = 3;
    j = 26;
    k = 223;
    do
    {
        do
        {
            while (--k);
        } while (--j);
    } while (--i);
}

  

 

  
1
  
2
  
3
  
4
  
5
  
6
  
7
  
8
  
9
  
10
  
11
  
12
  
13
  
14
  
15
  
16
  
17
  
18
  
19
  
20
  
21
  
22
  
23
  
24
  
25
  
26
  
27
  
28
  
29
  
30
  
31
  
32
  
33
  
34
  
35
  
36
  
37
  
38
  
39
  
40
  
41
  
42
  
43
  
44
  
45
  
46
  
47
  
48
  
49
  
50
  
51
  
52
  
53
  
54
  
55
  
56
  
57
  
58
  
59
  
60
  
61
  
62
  
63
  
64
  
65
  
66
  
67
  
68
  
69
  
70
  
71
  
72
  
73
  
74
  
75
  
76
  
77
  
78
  
79
  
80
  
81
  
82
  
83
  
84
  
85
  
86
  
87
  
88
  
89
  
90
  
91
  
92
  
93
  
94
  
95
  
96
  
97
  
98
  
99
  
100
  
101
  
102
  
103
  
104
  
105
  
106
  
107
  
108
  
109
  
110
  
111
  
112
  
113
  
114
  
115
  
116
  
117
  
118
  
119
  
120
  
121
  
122
  
123
  
124
  
125
  
126
  
127
  
128
  
129
  
130
  
131
  
132
  
133
  
134
  
135
  
136
  
137
  
138
  
139
  
140
  
141
  
142
  
143
  
144
  
145
  
146
  
147
  
148
  
149
  
150
  
151
 

配置流程：

1. CMOD 设置禁止溢出中断
2. 设置CCAPMx设置开启捕获中断，以及上升沿捕获还是下降沿捕获
3. 清零CCnPL、CCnPH以及CH、CL

其实最重要的还得看手册，介绍的真心很详细！！！

一个非常详细的电路图，分分享一下：

很明显，图的意思就是设置好上升沿捕获或者下降沿捕获后，由于CL、CH
一直在走，一旦满足条件就把CL./CH的值分别装入CCAPL以及CCAPH中，如果此时使能PCA中断的话，会触发中断进入中断。

文章来源: recclay.blog.csdn.net，作者：ReCclay，版权归原作者所有，如需转载，请联系作者。

原文链接：recclay.blog.csdn.net/article/details/75769620