sj8.asm

手动扩展外部中断INT0、INT1

data segment
mess1 db 'please press the keyboard',0ah,0dh,'$'
key   db  0c0h,0f9h,0a4h,0b0h,99h,92h,82h,0f8h,80h,98h
data ends
code segment
   assume cs:code,ds:data
start: mov ax,data
       mov ds,ax
       mov dx,20bh
       mov al,89h
       out dx,al
       lea dx,mess1
       mov ah,09h
       int 21h
   l0: mov cl,0
   l1: mov dx,20ah
       in  al,dx
       and al,01h
       cmp al,01h
       jz  exit
       mov dx,209h
       lea bx,key
       mov al,cl
       xlat
       out dx,al
       mov dx,208h
       mov al,01h
       out dx,al
       mov ah,01h
       int 21h
       inc cl
       cmp cl,10
       jz  l0
       jmp l1
 exit: mov ah,4ch
       int 21h
code ends
    end start