4*4矩阵键盘的实现代码

仿真

题目：按下16个矩阵键盘依次在数码管上显示1-16的平方。如按下第一个显示1，第二个显示4...
代码：

#include
#define uint  unsigned int
#define uchar unsigned char
***it dula=P2^6;
***it wela=P2^7;
uchar code table[]={
0x3f,0x06,0x5b,0x4f,
0x66,0x6d,0x7d,0x07,
0x7f,0x6f,0x77,0x7c,
0x39,0x5e,0x79,0x71};

uint num1;
uchar bai,shi,ge;

void delayms(uint xms)
{
uint i,j;
for(i=xms;i>0;i--)
for(j=110;j>0;j--);

}

void display(uchar bai, uchar shi, uchar ge) //显示函数只送段选数据
{
wela=1;
P0=0xfe;
wela=0;
P0=0xff;
dula=1;
P0=table[bai];
delayms(1);

wela=1;
P0=0xfd;
wela=0;
P0=0xff;
dula=1;
P0=table[shi];
delayms(1);

wela=1;
P0=0xfb;
wela=0;
P0=0xff;
dula=1;
P0=table[ge];
delayms(1);

}

uint matrixkeyscan()
{
uchar temp,key;

P3=0xfe;       //第一行键盘
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delayms(10); //消除按键抖动
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xee:
key=0;
break;
case 0xde:
key=1;
break;
case 0xbe:
key=4;
break;
case 0x7e:
key=9;
break;

}
while(temp!=0xf0)  //条件满足时是1；等待按键释放；
{
temp=P3;       //这两句是增加程序的稳定性
temp=temp&0xf0;
}

}
}

P3=0xfd;       //第二行键盘
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delayms(10); //消除按键抖动
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xed:
key=16;
break;
case 0xdd:
key=25;
break;
case 0xbd:
key=36;
break;
case 0x7d:
key=49;
break;

}
while(temp!=0xf0)  //条件满足时是1；等待按键释放；
{
temp=P3;       //这两句是增加程序的稳定性
temp=temp&0xf0;
}

}
}

P3=0xfb;       //第三行键盘
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delayms(10); //消除按键抖动
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xeb:
key=64;
break;
case 0xdb:
key=81;
break;
case 0xbb:
key=100;
break;
case 0x7b:
key=121;
break;

}
while(temp!=0xf0)  //条件满足时是1；等待按键释放；
{
temp=P3;       //这两句是增加程序的稳定性
temp=temp&0xf0;
}

}
}

P3=0xf7;          //第四行键盘
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
delayms(10); //消除按键抖动
temp=P3;
temp=temp&0xf0;
if(temp!=0xf0)
{
temp=P3;
switch(temp)
{
case 0xe7:
key=144;
break;
case 0xd7:
key=169;
break;
case 0xb7:
key=196;
break;
case 0x77:
key=225;
break;

}
while(temp!=0xf0)  //条件满足时是1；等待按键释放；
{
temp=P3;       //这两句是增加程序的稳定性
temp=temp&0xf0;
}

}
}
return key;
}

void main()
{
P0=0; //关闭所有数码管段选
dula=1;
dula=0;
P0=0xc0;  //位选中所有数码管
wela=1;
wela=0;
while(1)
{
num1=matrixkeyscan();  //不停的调用键盘扫描程序
bai=num1/100;
shi=(num1%100)/10;
ge=num1%10;
display(bai,shi,ge);

}
}

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