MYREG	EQU	0x08			
	ORG	0
BACK	MOVLW 	0x55		
	MOVWF  	PORTB		
	CALL 	DELAY		
	MOVLW	0xAA		
	MOVWF	PORTB		
	CALL	DELAY	
	GOTO 	BACK		
	ORG	300H		
DELAY	MOVLW	0xFF		
	MOVWF	MYREG
AGAIN	NOP			
	NOP
	DECF	MYREG, F	
	BNZ 	AGAIN		
	RETURN			
	END