1 程序：
2 assume cs:code
3 code segment
4 start:
5 mov ax,0b800h
6 mov es,ax
7 mov di,160*12+16*2
8 mov bx,offset s-offset se
9 mov cx,80
10 s:
11 mov byte ptr es:[di],'!'
12 add di,2
13 int 7ch
14 se:
15 nop
16 mov ax,4c00h
17 int 21h
18 code ends
19 end start
20 7ch中断例程：
21 assume cs:code
22 code segment
23 start:
24 mov ax,cs
25 mov ds,ax
26 mov si,offset do0
27
28 mov ax,0
29 mov es,ax
30 mov di,200h
31
32 mov cx,offset do0end-offset do0
33 cld
34 rep movsb
35
36 mov ax,0
37 mov ds,ax
38 mov word ptr ds:[7ch*4],200H
39 mov word ptr ds:[7ch*4+2],0H
40
41 mov ax,4c00h
42 int 21h
43
44 do0:
45 dec cx
46 jcxz ok
47 push bp
48 mov bp,sp
49 add [bp+2],bx
50 pop bp
51 ok:
52 iret
53
54 do0end:
55 nop
56
57 code ends
58 end start 转载于:https://www.cnblogs.com/crackkay/archive/2013/04/28/3048441.html