獨立按鍵矩陣鍵盤定時器消抖非延時消抖程序

ID:349802 · 發(fā)表于 2018-6-14 09:01

#include<reg52.h>

sbit KEY_IN_1 = P2^4;
sbit KEY_IN_2 = P2^5;
sbit KEY_IN_3 = P2^6;
sbit KEY_IN_4 = P2^7;
sbit KEY_OUT_1 = P2^3;
sbit KEY_OUT_2 = P2^2;
sbit KEY_OUT_3 = P2^1;
sbit KEY_OUT_4 = P2^0;

unsigned char KeySta[4][4] = {
{1,1,1,1},{1,1,1,1},{1,1,1,1},{1,1,1,1}
};
unsigned char code KeyCodeMap[4][4] = { //矩陣按鍵編號到標(biāo)準(zhǔn)鍵盤鍵碼的映射表
{ 0x31, 0x32, 0x33, 0x26 }, //數(shù)字鍵1、數(shù)字鍵2、數(shù)字鍵3、向上鍵
{ 0x34, 0x35, 0x36, 0x25 }, //數(shù)字鍵4、數(shù)字鍵5、數(shù)字鍵6、向左鍵
{ 0x37, 0x38, 0x39, 0x28 }, //數(shù)字鍵7、數(shù)字鍵8、數(shù)字鍵9、向下鍵
{ 0x30, 0x1B, 0x0D, 0x27 }  //數(shù)字鍵0、ESC鍵、  回車鍵、向右鍵
};
void  KeyDriver();
void main()
{
EA = 1;    //使能總中斷
TMOD = 0x01;  //設(shè)置T0為模式1
TH0  = 0xFC;  //為T0賦初值0xFC67，定時1ms
TL0  = 0x67;
ET0  = 1;    //使能T0中斷
TR0  = 1;    //啟動T0
while (1)
{
      KeyDriver(); //調(diào)用按鍵驅(qū)動函數(shù)
}
}

void KeyAction(unsigned char keycode) //按鍵處理函數(shù),根據(jù)不同鍵值執(zhí)行動作
{

if((keycode >= 0x30) &&(keycode <= 0x39)) //數(shù)字鍵
{

}

else if(keycode == 0x26) //向上鍵
{

}
else if(keycode == 0x25) //向左鍵
{

}
else if(keycode == 0x28) //向下鍵
{

}
else if(keycode == 0x27) //向右鍵
{

}
else if(keycode == 0x0D) //回車鍵
{

}
else if(keycode == 0x1B) //ESC鍵
{

}

}
void  KeyDriver()
{
unsigned char i, j;
static unsigned char backup [4][4] = {
{1,1,1,1},{1,1,1,1},{1,1,1,1},{1,1,1,1}
};

for(i=0; i<4; i++)
{
for(j=0; j<4; j++)
{
if(backup[i][j] != KeySta[i][j])
{
if(backup[i][j] == 0)
{
KeyAction(KeyCodeMap[i][j]);
}
backup[i][j] = KeySta[i][j];
}
}
}

}

/* 按鍵掃描函數(shù)，需在定時中斷中調(diào)用，推薦調(diào)用間隔1ms */
void KeyScan()
{
unsigned char i;
static unsigned char keyout = 0; //矩陣按鍵掃描輸出索引
static unsigned char keybuf[4][4] = {  //矩陣按鍵掃描緩沖區(qū)
      {0xFF, 0xFF, 0xFF, 0xFF},  {0xFF, 0xFF, 0xFF, 0xFF},
      {0xFF, 0xFF, 0xFF, 0xFF},  {0xFF, 0xFF, 0xFF, 0xFF}
};

//將一行的4個按鍵值移入緩沖區(qū)
keybuf[keyout][0] = (keybuf[keyout][0] << 1) | KEY_IN_1;
keybuf[keyout][1] = (keybuf[keyout][1] << 1) | KEY_IN_2;
keybuf[keyout][2] = (keybuf[keyout][2] << 1) | KEY_IN_3;
keybuf[keyout][3] = (keybuf[keyout][3] << 1) | KEY_IN_4;
//消抖后更新按鍵狀態(tài)
for (i=0; i<4; i++)  //每行4個按鍵，所以循環(huán)4次
{
      if ((keybuf[keyout][i] & 0x0F) == 0x00)
      { //連續(xù)4次掃描值為0，即4*4ms內(nèi)都是按下狀態(tài)時，可認(rèn)為按鍵已穩(wěn)定的按下
         KeySta[keyout][i] = 0;
      }
      else if ((keybuf[keyout][i] & 0x0F) == 0x0F)
      { //連續(xù)4次掃描值為1，即4*4ms內(nèi)都是彈起狀態(tài)時，可認(rèn)為按鍵已穩(wěn)定的彈起
         KeySta[keyout][i] = 1;
      }
}
//執(zhí)行下一次的掃描輸出
keyout++;             //輸出索引遞增
keyout = keyout & 0x03;  //索引值加到4即歸零
switch (keyout)       //根據(jù)索引，釋放當(dāng)前輸出引腳，拉低下次的輸出引腳
{
      case 0: KEY_OUT_4 = 1; KEY_OUT_1 = 0; break;
      case 1: KEY_OUT_1 = 1; KEY_OUT_2 = 0; break;
      case 2: KEY_OUT_2 = 1; KEY_OUT_3 = 0; break;
      case 3: KEY_OUT_3 = 1; KEY_OUT_4 = 0; break;
      default: break;
}
}

/* T0中斷服務(wù)函數(shù)，用于數(shù)碼管顯示掃描與按鍵掃描 */
void InterruptTimer0() interrupt 1
{
TH0 = 0xFC;
TL0 = 0x67;
KeyScan();
}