主程序：

＃i nclude <REGX52.H>

void Delay1ms(unsigned int count)
{
 unsigned int i,j;
 for(i=0;i<count;i++)
 for(j=0;j<120;j++);
}

main()
{
 unsigned char LEDIndex = 0;
 bit LEDDirection = 1;

 while(1)
 {
  if(LEDDirection)
   P1 = ~(0x01<<LEDIndex);
  else
   P1 = ~(0x80>>LEDIndex); 
  if(LEDIndex==7)
   LEDDirection = !LEDDirection;
  LEDIndex = (LEDIndex+1)%8;
  Delay1ms(100);
 }
}