【单片机期中测试】2.独立按键控制LED移位

#include<reg52.h>
#define uc unsigned char
sbit KEY1 = P3^1;
sbit KEY2 = P3^0;
void delay(uc c)
{
  uc a,b;
  for(;c>0;c--)
    for(a=38;a>0;a--)
      for(b=130;b>0;b--);
}
void main()
{
  uc LEDNum = 0;
  P2 = 0xFE;
  while(1)
  {
    if(KEY1 == 0)
    {
      delay(1);
      while(KEY1 == 0);
      delay(1);
      if(LEDNum >= 7) LEDNum = 0;   
      else
        LEDNum++;
      P2=~(0x01<<LEDNum); 
    }
    if(KEY2 == 0)
    {
      delay(1);
      while(KEY2 == 0);
      delay(1);
      if(LEDNum <= 0) LEDNum = 7;
      else
        LEDNum--;
      P2=~(0x01<<LEDNum);
    }
  }
}