ORG 0000H
			LJMP MAIN
			ORG 0030H
MAIN:		LCALL DELAY               ;quater second delay
			MOV P1,#000H
			MOV P3,#000H
			LCALL DELAY       ;quater second delay
			MOV P1,#0FFH
			MOV P3,#0FFH
			SJMP MAIN
DELAY:		MOV R7,#250
AGN:		MOV R6,#250
HRE:		NOP
			NOP
			DJNZ R6,HRE
			DJNZ R7,AGN
			RET
			END