1.asm

接口试验

DATA	SEGMENT	USE16
DATA	ENDS	

STACK	SEGMENT	STACK
	DB	200	DUP(0)
STACK	ENDS

CODE	SEGMENT	USE16
	ASSUME	DS:DATA,SS:STACK,CS:CODE
start:	MOV	DX,303H
	MOV	AL,89H
	OUT	DX,AL
	MOV	BL,0FEH 
	MOV	BH,7FH
LOOP1:	MOV	DX,302H
	IN	AL,DX
	TEST	AL,01H
	JZ	RIGHT
	TEST	AL,80H
	JZ	LEFT
	JMP	LOOP1

RIGHT:	MOV	AL,BH
	MOV	DX,300H
	OUT	DX,AL
	ROR	BH,1		;循环向右移动 一位
	MOV	AH,06H		;判断是否有按键
	MOV 	DL,0FFH
	INT 	21H
	JNZ	EXIT
	CALL DELAY		;调用延时函数

	MOV	DX,302H
	IN	AL,DX
	TEST	AL,80H
	JZ	LEFT
	JMP	RIGHT


LEFT:	MOV	AL,BL
	MOV	DX,300H
	OUT	DX,AL
	ROL	BL,1
	MOV	AH,06H	
	MOV 	DL,0FFH
	INT 	21H
	JNZ	EXIT
	CALL DELAY

	MOV	DX,302H
	IN	AL,DX
	TEST	AL,01H
	JZ	RIGHT
	JMP	LEFT
EXIT:	MOV	AH,4CH
	INT	21H

		


DELAY PROC	NEAR
	MOV	AX,1000;
	LLL:	MOV	CX,0
	LL:	LOOP LL
		DEC	AX
		JNE	LLL
	RET
DELAY	 ENDP
CODE	 ENDS
END	 START