芯片是采用的stc89c51單片機.

下面是矩陣鍵盤的電路圖，矩陣鍵盤是接在p2口的.

下面是單片機部分的圖,數碼管顯示等完整的原理圖可以從 http://www.zg4o1577.cn/f/ks51.pdf  這里下載

 

下面是程序源碼：

/********矩陣按鍵定時器消抖**************/
/**
*時間：2014年3月18日20:27:23
*作者：寒竹子
*工程寫法：用定時器為按鍵消抖不占用cpu的時間
**/

#include <reg52.h>

typedef unsigned int uint;
typedef unsigned char uchar;

//138
sbit ADDR0 = P1^0;
sbit ADDR1 = P1^1;
sbit ADDR2 = P1^2;
sbit ADDR3 = P1^3;
sbit ENLED = P1^4;

//KeyIn
sbit KeyIn1 = P2^4;
sbit KeyIn2 = P2^5;
sbit KeyIn3 = P2^6;
sbit KeyIn4 = P2^7;

//KeyOut
sbit KeyOut1 = P2^3;
sbit KeyOut2 = P2^2;
sbit KeyOut3 = P2^1;
sbit KeyOut4 = P2^0;

//數碼管編碼
uchar code table[] = { 
0xC0,  //"0"
                0xF9,  //"1"
                0xA4,  //"2"
                0xB0,  //"3"
                0x99,  //"4"
                0x92,  //"5"
                0x82,  //"6"
                0xF8,  //"7"
                0x80,  //"8"
                0x90,  //"9"
                0x88,  //"A"
                0x83,  //"B"
                0xC6,  //"C"
                0xA1,  //"D"
                0x86,  //"E"
                0x8E   //"F"
};

uchar key = 0;

//16個按鍵初始化1
uchar keysta[4][4] =
{
{1, 1, 1, 1}, //K1 - K4
{1, 1, 1, 1}, //K5 - K8
{1, 1, 1, 1}, //K9 - K 12
{1, 1, 1, 1} //K13 - K16
};

//16個按鍵的備份值初始值1
uchar keybackup[4][4] = {
{1, 1, 1, 1},
{1, 1, 1, 1}, 
{1, 1, 1, 1},
{1, 1, 1, 1}
};

void keymatrixScan();
void timer0_init();
void refresh();
void HC138_init();

void main()
{
timer0_init();
HC138_init();

while (1)
{
keymatrixScan();
}
}

/********timer0 init*************/
void timer0_init()
{
TMOD |= 0x01;
TMOD &= 0xF1; //1111 0001，配置T0方式1
TH0 = 0xFC;
TL0 = 0x67;//1ms
TR0 = 1;//start T0
EA = 1; //open main int
ET0 = 1;//open T0 int
}

/***********HC138 init*********/
void HC138_init()
{
ADDR3 = 1;
ENLED = 0;//使能U3
}

/***********刷新數碼管************/
void refresh()
{
static uchar j = 0;//刷新數碼管
P0 = 0xFF;//消隱
switch (j)
{
case 0: ADDR2 = 0; ADDR1 = 0; ADDR0 = 0;
break;
case 1: ADDR2 = 0; ADDR1 = 0; ADDR0 = 1;
break;
case 2: ADDR2 = 0; ADDR1 = 1; ADDR0 = 0;
break;
case 3: ADDR2 = 0; ADDR1 = 1; ADDR0 = 1;
break;
case 4: ADDR2 = 1; ADDR1 = 0; ADDR0 = 0;
break;
case 5: ADDR2 = 1; ADDR1 = 0; ADDR0 = 1;
break;
default:
break;
}
P0 = table[key]; //在此處送入顯示的數據，很正常的顯示出來，當放到while(1)中時會出現抖動
j++;
if (j >= 6)
{
j = 0;
}
}

/**********矩陣按鍵檢測***********/
void keymatrixScan()
{
//16個按鍵檢測
uchar i = 0, j = 0;
for (i = 0; i < 4; i++) //4行
{
for (j = 0; j < 4; j++) //4列
{
if (keysta[j] != keybackup[j]) //檢測第i行第j列按鍵是否有動作
{
if (keybackup[j] == 0) //若第i行第j列的按鍵的前一個狀態為0，則由0-1，即按鍵彈起
{
key = i * 4 + j;//按鍵定位
}
//備份當前按鍵的值，以備下一次比較
keybackup[j] = keysta[j];
}
}
}
}

/**********timer0 int****************/
void timer0_int() interrupt 1 using 3
{
static uchar keybuf[4][4] = {
{0xFF, 0xFF, 0xFF, 0xFF},
{0xFF, 0xFF, 0xFF, 0xFF},
{0xFF, 0xFF, 0xFF, 0xFF},
{0xFF, 0xFF, 0xFF, 0xFF}
};//16個按鍵的掃描緩沖區
static uchar keyout = 0;//按鍵的列，即KeyOut1 - KeyOut4
uchar i = 0;
TH0 = 0xFC;
TL0 = 0x67; //1ms

refresh();

//掃描第keyout列的按鍵的值
keybuf[keyout][0] = (keybuf[keyout][0] << 1) | KeyIn1;//將按鍵1的掃描值存入keybuf中
keybuf[keyout][1] = (keybuf[keyout][1] << 1) | KeyIn2;
keybuf[keyout][2] = (keybuf[keyout][2] << 1) | KeyIn3;
keybuf[keyout][3] = (keybuf[keyout][3] << 1) | KeyIn4; //每1ms掃描一列，4ms掃描四列，共掃描四位，設定掃描16ms，即每個按鍵掃描4次

//更新消抖后按鍵的值
for (i = 0; i < 4; i++) //4行, 一列4個按鍵
{
if ((keybuf[keyout] & 0x0F) == 0x00) //按鍵的緩沖區的低四位都是0，因為16ms只掃描了4次，移入了四位狀態值
{
keysta[keyout] = 0;//按鍵按下
}
else if ((keybuf[keyout] & 0x0F) == 0x0F) //按鍵的緩沖區的第四位都是1
{
keysta[keyout] = 1;//第keyout列第i行的按鍵彈起
}
}

//列++
keyout++;
//keyout 0-3
/*if (keyout >= 4)
keyout = 0;
*/
keyout &= 0x03;//當keyout到4則會等于3
//通過keyout列數選中列
switch (keyout)
{
case 0: KeyOut1 = 0; KeyOut4 = 1; KeyOut2 = 1; KeyOut3 = 1; //選中第一列，開發板上的第一行
break;
case 1: KeyOut2 = 0; KeyOut1 = 1; KeyOut3 = 1; KeyOut4 = 1;
break;
case 2: KeyOut3 = 0; KeyOut1 = 1; KeyOut2 = 1; KeyOut4 = 1;
break;
case 3: KeyOut4 = 0; KeyOut1 = 1; KeyOut2 = 1; KeyOut3 = 1;
break;
default:
break;
}
}

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