#include<REGX52.H>
#include<INTRINS.H>
void Delay(unsigned int x)
{
	unsigned char data i, j;
   while(x)
	 {
	 _nop_();
	i = 2;
	j = 199;
	do
	{
		while (--j);
	} while (--i);
		x--;
	 }
}

unsigned int LedNumber = 0;
void main()
	{ P2=0xFE;
	while(1)
	{   
		
		if(P3_1==0)
		{
			
			Delay(20);
			while(P3_1==0);
			Delay(20);
			LedNumber++;
			if(LedNumber > 8)
				LedNumber = 0;
			P2 = ~(0x01<<LedNumber);
			
		}
		if(P3_0==0)
		{
			Delay(20);
			while(P3_0==0);
			Delay(20);
			if(LedNumber==0)
				LedNumber=7;
			else
				LedNumber--;
			P2=~(0x01<<LedNumber);
		}
	}
}