按键

独立按键

独立按键

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char

void delay(uint timer)
{
    uchar j = 124;
    while(timer--)
    {
        while(j--);
    }
}

void main()
{
    uchar i;
        uchar keyVal=0;  //保存按键的值
        bit bFlash=1;   //保存灯的状态
        uchar i_val=0;
    
        P3=0xff;
      keyVal=P3;
    
    while(1)
    {
        for(i=0;i<8;i++)
        {
            if(keyVal!=P3)
                        {
                                keyVal=P3;
                                if((P3&0x04)==0)
                                {
                                    if(bFlash)
                                    {
                                        i_val=i;  //保存当前哪个灯在闪烁
                                    } else
                                    {
                                        i = i_val;
                                    }
                                bFlash = ~ bFlash;// ÐÞ¸ÄÉÁ˸״̬
                                }
                        }
                        if (bFlash)
                        {
                        P1 = ~(1<<i);
                        }
            delay(200);
        }
    }
}

复杂的按键程序

复杂的按键程序

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char

sbit k1=P3^2;
sbit k2=P3^3;
sbit led1=P2^5;
sbit led2=P2^6;

uchar code seg[] = {0xC0,0xF9,0xA4,0xB0,0x99,
                    0x92,0x82,0xF8,0x80,0x90,
                                        0xff,0x0c};

void delay(uint timer)
{
    uchar j = 124;
    while(timer--)
    {
        while(j--);
    }
}

void main()
{
        uchar keyVal=0;  
        
        P3=0xff;
      keyVal=P3;
    
      P0 = seg[11];
    
    while(1)
    {
        if(keyVal!=P3)
                {
                    keyVal=P3;
                    if(k1==0)
                    {
                        delay(10);
                        if(k1==0)
                        {
                            led1=0;
                            led2=1;
                            P0=seg[1];
                        }
                    }
                    if(k2==0)
                    {
                        delay(10);
                        if(k2==0)
                        {
                            led1=1;
                            led2=0;
                            P0=seg[2];
                        }
                    }
                }
                delay(20);
    }
}

按键复用

矩阵键盘

矩阵键盘

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char


uchar code seg[] = {
                                        0x3f,0x06,0x5b,0x4f,0x66,
                                        0x6d,0x7d,0x07,0x7f,0x6f,
                                       0x00};                                                                        
void delay(uint timer)
{       
    uchar j = 124;
    while(timer--)
    {
        while(j--);
    }
}

void display(uint num)
{
        P2 = 0xfd;
        P0 = seg[num%10];
        delay(5);
    
        P2 = 0xfe;
        P0 = seg[num/10];
        delay(5);
}


uchar keyscan()
{
        uchar key_val = 0;
        uchar tmp = 0;
        
        P3 = 0x0f;
        delay(1);
        if(P3 != 0x0f)
        {
                delay(10);
                if(P3 != 0x0f)
                {
                        tmp = P3^0x0f;
                        switch(tmp)
                        {
                            case 1: key_val = 1; break;
                            case 2: key_val = 2; break;
                            case 4: key_val = 3; break;
                            case 8: key_val = 4; break;
                            default: key_val = 0;
                        }   
                 P3 = 0xf0;
                 delay(1);
                 tmp = P3^0xf0;
                 switch(tmp)
                        {
                            case 0x10: key_val += 0; break;
                            case 0x20: key_val += 4; break;
                            case 0x40: key_val += 8; break;
                            case 0x80: key_val += 12; break;
                            default: key_val = 0;
                        }   
                }
        }
        
        return key_val;
}

void main()
{       
        uchar key_val = 0;
        uchar tmp = 0;
         
        P0 = 0xff;
        P2 = 0xff;
        
        key_val = 0;
        while(1)
        {
            tmp = keyscan();
            if(key_val != tmp)
            {
                    if(tmp != 0)
                    {
                        key_val = tmp;
                    }
            }
            display(key_val);
        }
}

应用编码器74ls148

应用编码器74ls148

#include <reg51.h>

#define uint unsigned int
#define uchar unsigned char


uchar code seg[] = {0xC0,0xF9,0xA4,0xB0,0x99,
                    0x92,0x82,0xF8,0x80,0x90,
                                        0xff,0x0c};

void int1_init() interrupt 2
{   
        
        P0 = seg[P3&0x07];
}


void main()
{       
        EA  = 1;
        EX1  = 1;
        IT1  = 1;
        P0 = seg[0];
        while(1)
        {
                
        }
}