《汇编语言》（第三版）王爽第十三章实验13.1个人方法记录

7C中断信号的修改
代码如下
assume cs:code
code segment
start:
mov ax,code
mov ds,ax
mov si,offset ls
mov ax,0
mov es,ax
mov di,0200H
mov cx,offset lend-offset ls
cld
rep movsb

mov ax,0
mov ds,ax
mov word ptr ds:[1F0H],0200H
mov word ptr ds:[1F2H],0000H

mov ax,4C00H
int 21H
ls:
mov ax,0B800H
mov es,ax
mov al,160
dec dh
mul dh
mov dh,0
dec dl
add dl,dl
add al,dl
mov di,ax
mov di,ax
mov ah,cl
;=============================================
display:
mov al,[si]
mov es:[di],ax
mov es:[di],ax
add di,2
inc si
cmp al,0
je return
jmp display
;=============================================
return:
iret
lend:nop

code ends
end start
运行结果如下