#include <reg52.h>
void delay(int n)
{
     int i,j;
	 for (i=1;i<=n;i++)
	     for (j=1;j<=n;j++)
		     ;
}
int main(void)
{
    int output=0x01;
	while(1)
	{
	    if (output & 0x80)
		    output = 0x01;
		else 
		{
		    output = output<<1;
			p1 = output;
		}
		delay(100);
	}
    return 0;
}