51单片机学习笔记：独立按键s2按下数码管加一（缺陷版）

按下数码管就灭

 

在学习了独立按键后，就产生了这个想法。所以今天就把他实现了出来：

 

#include<reg52.h>

sbit KEY_s2 = P3^0;  //定义按键s2
sbit WE = P2^7;  //定义位选
sbit DU = P2^6;  //定义段选
unsigned int code table[10] = {0x3F, 0x06, 0x5B, 0x4F, 0x66, 0x6D, 0x7D, 0x07, 0x7F, 0x6F};
unsigned int code duan[10] = {0,0xFE,0xFD,0xFB,0xF7,0xEF,0xDF,0xBF,0x7F};

void delay()  //20ms延时函数   （用于键盘消抖）
{
    unsigned char a,b,c;
    for(c=1;c>0;c--)
        for(b=222;b>0;b--)
            for(a=40;a>0;a--);
}

void softwaredelay()   //用于动态显示数码管
{
   unsigned char a,b;
    for(b=102;b>0;b--)
        for(a=3;a>0;a--);
}

void digitaltube(unsigned int du,unsigned int num)
{
    if(num == 0)
    {
        
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[0];
        DU = 0;
    }
    if(num == 1)
    {
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[1];
        DU = 0;
    }
    if(num == 2)
    {
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[2];
        DU = 0;
    }
    if(num == 3)
    {
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[3];
        DU = 0;
    }
    if(num == 4)
    {
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[4];
        DU = 0;
    }
    if(num == 5)
    {
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[5];
        DU = 0;
    }
    if(num ==6)
    {
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[6];
        DU = 0;
    }
    if(num == 7)
    {
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[7];
        DU = 0;
    }
    if(num == 8)
    {
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[8];
        DU = 0;
    }
    if(num == 9)
    {
        P0 = 0xFF;
        WE = 1;
        P0 = duan[du];
        WE = 0;
        
        DU = 1;
        P0 = table[9];
        DU = 0;
    }
}    

void main()
{
    unsigned int sec = 0;
    unsigned int dt4;
    unsigned int dt3;
    unsigned int dt2;
    unsigned int dt1; 
    
    while(1)
    {
        if(KEY_s2 == 0)
        {
            delay();  //键盘消抖
            if(KEY_s2 == 0)
            {
                sec ++;
                while(!KEY_s2);
            }
        }
        //松键盘后数码管显示加1
    dt4 = sec % 10;
    dt3 = (sec / 10) % 10;
    dt2 = (sec / 100) % 10;
    dt1 = (sec/ 1000) % 10;
    digitaltube(1 , dt1);
    softwaredelay();
    digitaltube(2 , dt2);
    softwaredelay();
    digitaltube(3 , dt3);
    softwaredelay();
    digitaltube(4 , dt4);
    softwaredelay();
    }
}

但是在烧录到单片机里执行的时候会发现在按键按下时，数码管是熄灭的......这就涉及到了中断的问题。我们下一个笔记会探讨一下这个程序的中断版本。