#include <REGX51.H>
int num=0;
unsigned char a[]={0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80};
void delay(){
unsigned char i,j;
for(i=0;i<20;i++){
for(j=0;j<120;j++);
}
}
void scan()
{
int temp1=0,temp2=0,temp=0;
P1=0x0f;
delay();
if(P1!=0x0f){
temp1=P1;
P1=0xf0;
delay();
if(P1!=0xf0){
temp2=P1;
}
}
temp=temp1+temp2;
if(temp2==0xe0||temp2==0xd0){
switch (temp){
case 0xee:num=0;break;
case 0xed:num=1;break;
case 0xeb:num=2;break;
case 0xe7:num=3;break;
case 0xde:num=4;break;
case 0xdd:num=5;break;
case 0xdb:num=6;break;
case 0xd7:num=7;break;
}
}
}
void main(){
P2=a[num];
while(1){
scan();
P2=a[num];
}
} |