第1个回答 2017-08-10
# include<reg51.h>
# define uchar unsigned char
# define uint unsigned int
sbit key3=P2^0;
void delay(uint ms)
{
uchar i;
while(ms--)
{
for(i=100;i>0;i--);
}
}
void main()
{
P0=0x00;
P2=0xe7;
P3=0xcf;
if(key3==0)
P0=0xff;
while(!key3) ;
}本回答被网友采纳