v3.asm

data segment

data ends

stackseg segment stack
	db 400 dup(0)
	TOP equ 400
stackseg ends

code segment
assume cs:code, ds:data, ss:stackseg


delay0 proc near
	push dx
	push cx
	xor ax, ax
	int 1ah
	mov cs:Times, dx
	mov cs:Times[2], cx
  read_time0:
	xor ax, ax
	int 1ah
	sub dx, cs:Times
	sbb cx, cs:Times[2]
	cmp dx, Diads
	;jb表示小于则跳转，ja表示大于则跳转
	jb read_time0
	pop cx
	pop dx
	ret
delay0 endp

delay proc near
	push dx
	push cx
	xor ax, ax
	int 1ah
	mov cs:Times, dx
	mov cs:Times[2], cx
  read_time:
  	mov ah, 01h	;check if a key is pressed
	int 16h
	jz notpressed	;zero = no pressed
  	mov ah, 0
	int 16h
	mov dl, al
	cmp dl, 'z'
	jnz judgeZ
	mov dl, 'a'
	sub dl, 1h
	cmp dl, 'Z'
  judgeZ:
	cmp dl, 'Z'
	jnz getsecret
	mov dl, 'A'
	sub dl, 1h	
  getsecret:
	add dl, 1h
	mov ah, 2h
	int 21h
  notpressed:
	xor ax, ax
	int 1ah
	sub dx, cs:Times
	sbb cx, cs:Times[2]
	cmp dx, Diads
	;jb表示小于则跳转，ja表示大于则跳转
	jb read_time
	pop cx
	pop dx
	ret
Times	dw	0, 0
delay endp
;--------------------------------------------------------
Diads	equ		182	;延时10s

start:
	mov ax, data
	mov ds, ax
	mov ax, stackseg
	mov ss, ax
	mov sp, TOP
	
	mov al, 13h
	out 20h, al
	mov al, 8h
	out 21h, al
	mov al, 01h
	out 21h, al
	
	cli
    mov ax,offset keyboard
    mov word ptr es:[36],ax
    mov ax,seg keyboard   
    mov word ptr es:[38],ax
    sti
	
	call delay0
	;call keyboard

    mov dx,offset leave
    int 27h

keyboard:
	push cx
	push ax
	push bx
	
	pushf
	pushf
	pop ax
	and ah, 11111100b
	push ax
	popf
	
	mov bx, 3h
  domore:
	mov al, 02H ;写OCW1，屏蔽IR5、IR6、IR7中断源
	out 21h, al	 ;假定这三个中断输入未用,其他开中断
	call delay
	
	mov al, 00H
	out 21h, al
	call delay
	
	sub bx, 1h
	jnz domore
	
	pop bx
	pop ax
	pop cx
	iret

leave:
	code ends

end start