_____________________________________________________________
功能:同时按键抢答,先按的有效,其他按键锁死,复位后进行下一轮抢答
时间:2010—7—19
_____________________________________________________________
#include<reg52.h>
sbit key1=P3^0;
sbit key2=P3^1;
sbit key3=P3^2;
sbit key4=P3^3;
main()
{
bit Flag;
while(!Flag)
{
if(!key1)
{
P1=0xFE;
Flag=1;
}
else if(!key2)
{
P1=0xFD;
Flag=1;
}
else if(!key3)
{
P1=0xFB;
Flag=1;
}
else if(!key4)
{
P1=0xF7;
Flag=1;
}
}
while(Flag);
}
