单片机入门：按键控制LED灯移位

#include <reg52.h>
#include <intrins.h>
#define uchar unsigned char
#define uint unsigned int

void DelayMS(uint x)
{
   uchar i;
  while(x--)
  {
     for(i=200;i>0;i--);
  }
}

void Move_LED()
{
   if((P1 &= 0x10)==0)  P0 = _cror_(P0,1);
  else if((P1 &= 0x20)==0)  P0 = _crol_(P0,1);
  else if((P1 &= 0x40)==0)  P2 = _cror_(P2,1);
  else if((P1 &= 0x80)==0)  P2 = _crol_(P2,1);
}

void main()
{
   uchar Recent_Key=0xff;
  P0=0xfe;
  P1=0xfe;
  P2=0xfe;
  while(1)
  {
     if(Recent_Key != P1)
    {
       Recent_Key=P1;
      Move_LED();
      DelayMS(10);
    }
  }
}