4x4 矩阵键盘

最新推荐文章于 2024-08-13 10:30:50 发布

charrp

最新推荐文章于 2024-08-13 10:30:50 发布

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分类专栏： MC9S12XS 文章标签： delay

本文链接：https://blog.youkuaiyun.com/charrp/article/details/7882039

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#define KEYIO PT1AD0
#define KEYIODDR DDR0AD0

//=================== 按键扫描 ======================
uchar KeyScan(void) 
{
    uchar keyValue = 0;
    
    KEYIODDR = 0xFF;   //初始化 AD[15:8]输出 
    KEYIO = 0xF0;      //列=高电平 行=低电平  
    delay_ms(1);           
    KEYIODDR = 0xF0;   //AD[15:12]输出 AD[11:8]输入  扫描行值   
    delay_ms(1);  
    if(KEYIO != 0xF0) 
    { 
        KEYIO = 0xF0;      //列=高电平 行=低电平      
        delay_ms(10);               
        if(KEYIO != 0xF0) 
        {
            keyValue = KEYIO & 0x0F;    //保存行值           
            delay_ms(1); 
            KEYIODDR = 0xFF;    //初始化 AD[15:8 ]输出
            KEYIO = 0x0F;       //列=低电平 行=高电平            
            delay_ms(1);                        
            KEYIODDR = 0x0F;   //AD[15:12]输入 AD[11:8]输出 扫描列值               
            delay_ms(1);                            
            keyValue |= (KEYIO & 0xF0); //合并行列值            
            KEYIO = 0x0F;       //列=低电平 行=高电平 
            delay_ms(1);
            while(KEYIO != 0x0F);  //等待按键释放
            
            switch(keyValue) 
            {
              case 0x88: keyValue = 0x01;break;
              case 0x84: keyValue = 0x02;break;
              case 0x82: keyValue = 0x03;break;
              case 0x81: keyValue = 0x0A;break;
              case 0x48: keyValue = 0x04;break;
              case 0x44: keyValue = 0x05;break;
              case 0x42: keyValue = 0x06;break;
              case 0x41: keyValue = 0x0B;break;
              case 0x28: keyValue = 0x07;break;
              case 0x24: keyValue = 0x08;break;
              case 0x22: keyValue = 0x09;break;
              case 0x21: keyValue = 0x0C;break;
              case 0x18: keyValue = 0x0E;break;
              case 0x14: keyValue = 0x00;break;
              case 0x12: keyValue = 0x0F;break;
              case 0x11: keyValue = 0x0D;break;
              default: keyValue=0;break;       
            }            
            return (keyValue + 1);   
        }
    }  
    return keyValue;
}