ORG	0000H
		LJMP	MAIN		
		ORG	000BH		
		CPL	P2.1		
		RETI			
		ORG	0030H		
MAIN:		MOV	TMOD,#02H	
	  	MOV	P0,#0FFH	
		MOV	TH0,#-92	
		MOV	IE,#82H	
		SETB	TR0		
BACK:		MOV	A,P0		
		MOV	P1,A		
		SJMP	BACK		
					
		END