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| /\* Main.c file generated by New Project wizard
\* 4X4矩阵按键显示0-F
\* Created: 周三 6月 15 2022
\* Processor: AT89C52
\* Compiler: Keil for 8051
\*/
#include <reg52.h>
sbit ADDR0 = P1^0;
sbit ADDR1 = P1^1;
sbit ADDR2 = P1^2;
sbit ADDR3 = P1^3;
sbit ENLED = P1^4;
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 code LedChar[] = { //数码管显示字符转换表
0xC0, 0xF9, 0xA4, 0xB0, 0x99, 0x92, 0x82, 0xF8,
0x80, 0x90, 0x88, 0x83, 0xC6, 0xA1, 0x86, 0x8E
};
unsigned char KeySta[4][4] = { //全部矩阵按键的当前状态
{1, 1, 1, 1}, {1, 1, 1, 1}, {1, 1, 1, 1}, {1, 1, 1, 1}
};
void main()
{
unsigned char i, j;
unsigned char backup[4][4] = { //按键值备份，保存前一次的值
{1, 1, 1, 1}, {1, 1, 1, 1}, {1, 1, 1, 1}, {1, 1, 1, 1}
};
EA = 1; //使能总中断
ENLED = 0; //选择数码管 DS1 进行显示
ADDR3 = 1;
ADDR2 = 0;
ADDR1 = 0;
ADDR0 = 0;
TMOD = 0x01; //设置 T0 为模式 1
TH0 = 0xFC; //为 T0 赋初值 0xFC67，定时 1ms
TL0 = 0x67;
ET0 = 1; //使能 T0 中断
TR0 = 1; //启动 T0
P0 = LedChar[0]; //默认显示 0
while (1)
{
for (i=0; i<4; i++) //循环检测 4\*4 的矩阵按键
{
for (j=0; j<4; j++)
{
if (backup[i][j] != KeySta[i][j]) //检测按键动作
{
if (backup[i][j] != 0) //按键按下时执行动作
{
P0 = LedChar[i\*4+j]; //将编号显示到数码管
}
backup[i][j] = KeySta[i][j]; //更新前一次的备份值
}
}
}
}
}
/\* T0 中断服务函数，扫描矩阵按键状态并消抖 \*/
void InterruptTimer0() interrupt 1
{
unsigned char i;
static unsigned char keyout = 0; //矩阵按键扫描输出索引
static unsigned char keybuf[4][4] = { //矩阵按键扫描缓冲区
{0xFF, 0xFF, 0xFF, 0xFF}, {0xFF, 0xFF, 0xFF, 0xFF},
{0xFF, 0xFF, 0xFF, 0xFF}, {0xFF, 0xFF, 0xFF, 0xFF}
};
TH0 = 0xFC; //重新加载初值
TL0 = 0x67;
//将一行的 4 个按键值移入缓冲区
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;
//消抖后更新按键状态
for (i=0; i<4; i++) //每行 4 个按键，所以循环 4 次
{
if ((keybuf[keyout][i] & 0x0F) == 0x00)
{ //连续 4 次扫描值为 0，即 4\*4ms 内都是按下状态时，可认为按键已稳定的按下
KeySta[keyout][i] = 0;
}
else if ((keybuf[keyout][i] & 0x0F) == 0x0F)
{ //连续 4 次扫描值为 1，即 4\*4ms 内都是弹起状态时，可认为按键已稳定的弹起
KeySta[keyout][i] = 1;
}
}
//执行下一次的扫描输出
keyout++; //输出索引递增
keyout = keyout & 0x03; //索引值加到 4 即归零
switch (keyout) //根据索引，释放当前输出引脚，拉低下次的输出引脚
{
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;
}
}
|
