#include <reg52.h>
typedef unsigned char uint8;

sbit ENLED = P1^4;
sbit ADDR3 = P1^3;
sbit ADDR2 = P1^2;
sbit ADDR1 = P1^1;
sbit ADDR0 = P1^0;
sbit DB0 = P0^0;

void main()
{ 
	unsigned char i,k,p,t,j;
	char l;
	unsigned char a[]={0,1,2,4,6,16,32,64};									 
	unsigned char b[]={0,34,48,59,68,76,84,91,97,103,109,114,119,123,126};	  
	signed   char c[]={-7,-6,-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7};
	
	ENLED=0;ADDR3=1;
	ADDR0=0;ADDR1=1;ADDR2=1;
	P0=0xFF;

while(1)
{
k=0;
for(i=0;i<=252;i++)
{	
	if(0==(i%4)) k++;
	for(t=0;t<=16;t++)
	{
		DB0=0;
		for(j=0;j<=64;j++)
		if(j==k) DB0=1;
	}
}				


for(j=0;j<=254;j++)
{
	p=0;
	for(k=0;k<=15;k++)
	{if(j==b[k]) l=c[k];}

	for(i=0;i<=64;i++)
	{
		for(k=0;k<=7;k++)
		{					
			if(i==a[k]) 
			{
				p=p|(1<<k);
				t=~p;
				if(l>=0)
				P0=~(t<<l);
				else
				P0=~(t>>-l);
			}
		}
	}
}
}
}