51单片机(AT89C52)矩阵键盘检测程序

#include<reg52.h>
#define uchar unsigned char
#define uint unsigned int
sbit dula=P3^0;
sbit wela=P3^1;
#define keyport (P1)
#define keystate0 0		//按键确认状态
#define keystate1 1		//按键无动作状态
char keystate=1;	//按键状态初始化为按键无动作状态
uchar keynum=0;
void delayms(uint x)	//1ms
{
uint y,z;
for(y=x;y>0;y--)
for(z=111;z>0;z--);
}
uchar code table[]={	//共阳数码管
0xc0,0xf9,0xa4,0xb0,
0x99,0x92,0x82,0xf8,
0x80,0x90,0x88,0x83,
0xc6,0xa1,0x86,0x8e};
void smg()
{
dula=0;
wela=0;
P2=0x01;
wela=1;
wela=0;
P2=table[keynum];
dula=1;
dula=0;
delayms(1);

P2=0x02;
wela=1;
wela=0;
P2=table[keynum];
dula=1;
dula=0;
delayms(1);

P2=0x04;
wela=1;
wela=0;
P2=table[keynum];
dula=1;
dula=0;
delayms(1);

P2=0x08;
wela=1;
wela=0;
P2=table[keynum];
dula=1;
dula=0;
delayms(1);

P2=0x10;
wela=1;
wela=0;
P2=table[keynum];
dula=1;
dula=0;
delayms(1);

P2=0x20;
wela=1;
wela=0;
P2=table[keynum];
dula=1;
dula=0;
delayms(1);

P2=0x40;
wela=1;
wela=0;
P2=table[keynum];
dula=1;
dula=0;
delayms(1);

P2=0x80;
wela=1;
wela=0;
P2=table[keynum];
dula=1;
dula=0;
delayms(1);
}
void keyscan()
{
uchar temp1,temp2,column,row;
switch(keystate)
{
case keystate0:	//keystate0，按键按下确认状态，下一状态为keystate1(按键无动作状态)
keyport=0x0f;
temp1=keyport;
keyport=0xf0;
temp2=keyport;
if((temp1|temp2)!=0xff)
{
temp1|=temp2;
if(!(temp1&0x80))
row=3;
else
if(!(temp1&0x40))
row=2;
else
if(!(temp1&0x20))
row=1;
else
if(!(temp1&0x10))
row=0;
if(!(temp1&0x08))
column=3;
else
if(!(temp1&0x04))
column=2;
else
if(!(temp1&0x02))
column=1;
else
if(!(temp1&0x01))
column=0;
keynum=column*4+row;
while(!(keyport==0x0f|keyport==0xf0));
keystate=keystate1;
break;

}
else
keystate=keystate1;
break;
case keystate1:	//keystate1，按键无动作状态，下一状态为keystate0(按键无动作状态)
keyport=0x0f;
temp1=keyport;
keyport=0xf0;
temp2=keyport;
if((temp1|temp2)!=0xff)
{
keystate=keystate0;
}
else
keystate=keystate1;
break;
}
}
void main()
{
while(1)
{
keyscan();
smg();
}
}