data segment
ioport          equ 0c400h-0280h
io8255a         equ ioport+28ah
io8255b         equ ioport+28bh
portc1  db  24h,44h,04h,44h,04h,44h,04h   ;六個(gè)燈可能
	db  81h,82h,80h,82h,80h,82h,80h   ;的狀態(tài)數(shù)據(jù)
	db  0ffh                          ;結(jié)束標(biāo)志
data ends
code  segment
      assume  cs:code,ds:data
start:
	mov   ax,data
	mov   ds,ax
	mov   dx,io8255b
	mov   al,90h
	out   dx,al           ;設(shè)置8255為C口輸出
	mov   dx,io8255a
re_on:  mov   bx,0
on:     mov   al,portc1[bx]
	cmp   al,0ffh
	jz    re_on
	out   dx,al           ;點(diǎn)亮相應(yīng)的燈
	inc   bx
	mov   cx,0ffffh           ;參數(shù)賦初值
	test  al,21h          ;是否有綠燈亮
	jz    de1             ;沒(méi)有,短延時(shí)
	mov   cx,0ffffh         ;有,長(zhǎng)延時(shí)
de1:    mov   di,0ffffh         ;di賦初值
de0:    dec   di              ;減1計(jì)數(shù)
	jnz   de0             ;di不為0
	loop  de1
	push dx
	mov ah,06h
	mov dl,0ffh
	int 21h
	pop dx
	jz  on                ;沒(méi)有,轉(zhuǎn)到on
exit:   mov   ah,4ch          ;返回
	int   21h
code ends
	end start