STC89C52单片机实现独立按键控制LED显示二进制

#include <REGX52.H>

void Delay(unsigned int xms)    //@12.000MHz
{
  unsigned char i, j;
    while(xms--)
    {
    i = 2;
    j = 239;
    do
    {
      while (--j);
    } while (--i);
  }
}

void main()
{
    unsigned char LEDNum=0;
    while(1)
    {
      if(P3_1 == 0)
      {
        Delay(20);
        while(P3_1==0);
        Delay(20);
        LEDNum++;
        P2=~LEDNum;
      }
    }

}