gyw.c

说明：《AT89S51单片机试验》的仿真

#include <AT89X51.H>
unsigned int key;
unsigned int temp;
void delay();//定义延时函数
unsigned char code tabll[]={0x3f,0x06,0x5b,0x4f, 

                            0x66,0x6d,0x7d,0x07, 

                            0x7f,0x6f,0x77,0x7c, 

                            0x39,0x5e,0x79,0x71,0x00};


void main()
{

P0=0;
while(1){
P3=0xff;
P3_4=0;
temp=P3;
if((temp&0x0f)!=0x0f)
{
delay();
temp=P3;
if ((temp&0x0f)!=0x0f){
switch(temp)
{
case 0xee:key=3;break;
case 0xed:key=2;break;
case 0xeb:key=1;break;
case 0xe7:key=0;break;
}

P2=tabll[key];//扫描第一行




}}

P3=0xff;//扫描第二行
P3_5=0;
temp=P3;
if((temp&0x0f)!=0x0f)
{
delay();
temp=P3;
if ((temp&0x0f)!=0x0f){
switch(temp)
{
case 0xde:key=7;break;
case 0xdd:key=6;break;
case 0xdb:key=5;break;
case 0xd7:key=4;break;
}

P2=tabll[key];
}
}

P3=0xff;//扫描第三行
P3_6=0;
temp=P3;
if((temp&0x0f)!=0x0f)
{
delay();
temp=P3;
if ((temp&0x0f)!=0x0f){
switch(temp)
{
case 0xbe:key=11;break;
case 0xbd:key=10;break;
case 0xbb:key=9;break;
case 0xb7:key=8;break;
}

P2=tabll[key];

}

}






P3=0xff;//扫描第四行
P3_7=0;
temp=P3;
if((temp&0x0f)!=0x0f)
{
delay();
temp=P3;
if ((temp&0x0f)!=0x0f){
switch(temp)
{
case 0x7e:key=15;break;
case 0x7d:key=14;break;
case 0x7b:key=13;break;
case 0x77:key=12;break;
}

P2=tabll[key];









}
}


}}







void delay()// 延时函数
{
unsigned int i,j;
for(i=50;i>0;i--) 
          for(j=200;j>0;j--);

}