#include<reg52.h>
#define uint unsigned int
#define uchar unsigned char
sbit Row1=P1^4;
sbit Row2=P1^5;
sbit Row3=P1^6;
sbit Row4=P1^7;
void delayms(uint);
void Key_Scan(void);
void main(void)
{
while(1)
{
Key_Scan();
}
}
void delayms(uint z)
{
uint x,y;
for(x=z;x>0;x--)
for(y=100;y>0;y--);
}
void Key_Scan(void)
{
uint ucKeyValue;
P1=0xff;
Row1=0;
ucKeyValue=(P1&0x0f);
if(ucKeyValue!=0x0f)
{
delayms(10);
ucKeyValue=(P1&0x0f);
if(ucKeyValue!=0x0f)
{
switch(ucKeyValue)
{
case 0x0e:P0=0xfe;break;
case 0x0d:P0=0xfd;break;
case 0x0b:P0=0xfb;break;
case 0x07:P0=0xf7;break;
default:break;
}
}
}
P1=0xff;
Row2=0;
ucKeyValue=(P1&0x0f);
if(ucKeyValue!=0x0f)
{
delayms(10);
ucKeyValue=(P1&0x0f);
if(ucKeyValue!=0x0f)
{
switch(ucKeyValue)
{
case 0x0e:P0=0xfe;break;
case 0x0d:P0=0xfd;break;
case 0x0b:P0=0xfb;break;
case 0x07:P0=0xf7;break;
default:break;
}
}
}
P1=0xff;
Row3=0;
ucKeyValue=(P1&0x0f);
if(ucKeyValue!=0x0f)
{
delayms(10);
ucKeyValue=(P1&0x0f);
if(ucKeyValue!=0x0f)
{
switch(ucKeyValue)
{
case 0x0e:P0=0xfe;break;
case 0x0d:P0=0xfd;break;
case 0x0b:P0=0xfb;break;
case 0x07:P0=0xf7;break;
default:break;
}
}
}
P1=0xff;
Row4=0;
ucKeyValue=(P1&0x0f);
if(ucKeyValue!=0x0f)
{
delayms(10);
ucKeyValue=(P1&0x0f);
if(ucKeyValue!=0x0f)
{
switch(ucKeyValue)
{
case 0x0e:P0=0xfe;break;
case 0x0d:P0=0xfd;break;
case 0x0b:P0=0xfb;break;
case 0x07:P0=0xf7;break;
default:break;
}
}
}
}
附上4*4的矩阵行扫描程序和原理图！