CODE SEGMENT
ASSUME CS:CODE,DS:CODE,ES:CODE,SS:CODE ;

PPIC_C EQU 1FH	
PPIC EQU 1DH
PPIB EQU 1BH
PPIA EQU 19H

	ORG 1000H
	MOV AL,10000000B
	OUT PPIC_C,AL
	
	MOV AL,11111111B
	OUT PPIA,AL
	
	MOV AL,00000000B
	OUT PPIC,AL
	
L2: 	MOV AL,11101110B
		
L3:		OUT PPIB,AL
		ROL AL,1
		CALL TIMER
		JMP L3

TIMER:	MOV CX,3

TIMER2:	PUSH CX
		MOV CX,0FFH

TIMER1:	NOP
		NOP
		NOP
		NOP
		LOOP TIMER1
		POP CX
		LOOP TIMER2
		RET
		
CODE ENDS
END