日志
51单片机矩阵键盘
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//51单片机矩阵键盘C程序
#include <reg52.h>
#define uchar unsigned char
#define uint unsigned int
sbit we = P2^7;
sbit du = P2^6;
uchar KeyValue = 22; //按键值
uchar code leddata[16]={
0x3F, //"0"
0x06, //"1"
0x5B, //"2"
0x4F, //"3"
0x66, //"4"
0x6D, //"5"
0x7D, //"6"
0x07, //"7"
0x7F, //"8"
0x6F, //"9"
0x77, //"A"
0x7C, //"B"
0x39, //"C"
0x5E, //"D"
0x79, //"E"
0x71, //"F"
};
void delay(uint z)
{
uint x,y;
for(x = z; x > 0; x--)
for(y = 114; y > 0 ; y--);
}
void KeyScan() //带返回值的子函数
{
P3 = 0xf0;//判断哪一列被按下
if(P3 != 0xf0)
{
delay(5);//软件消抖
if( P3 != 0xf0)
{
switch(P3)
{
case 0xe0: KeyValue = 0; break;
case 0xd0: KeyValue = 1; break;
case 0xb0: KeyValue = 2; break;
case 0x70: KeyValue = 3; break;
}
P3 = 0x0f;//判断哪一行被按下
switch(P3)
{
case 0x0e: KeyValue = KeyValue; break;
case 0x0d: KeyValue += 4; break;
case 0x0b: KeyValue += 8; break;
case 0x07: KeyValue += 12; break;
}
while(P3 != 0x0f);//松手检测
}
}
}
void main()
{
we = 1;//打开位选
P0 = 0;//八位数码管全显示
we = 0;//锁存位选
du = 1;//打开段选端
P0 = 0;
while(1)
{
KeyScan();
P0 = leddata[KeyValue];
}
}
