MOV 	TMOD,#01100000B		
							
		MOV	TH1,#0			
		SETB	P3.5				
AGAIN:	SETB	TR1				
BACK:		MOV	A,TL1				
		MOV	P2,A				
		JNB	TF1,BACK			
		CLR	TR1				
		CLR	TF1				
		SJMP	AGAIN