CNT3		EQU 3FD6H
APORT3		EQU 3FD0H
BPORT3		EQU 3FD2H
CPORT3		EQU 3FD4H
RAME		EQU 0FFFFH

CODE 	SEGMENT
	ASSUME 	CS:CODE,   DS:CODE

	ORG  0

START:	MOV SP,RAME
	MOV AL,90H
	MOV DX,CNT3
	OUT DX,AL

J1:	MOV DX,APORT3
	IN AL,DX
	NOT AL
	MOV DX,BPORT3
	OUT DX,AL
	JMP  J1

CODE    ENDS
	END START