p.asm

微机原理——接口应用编程源码

stack segment
  dw 64 dup(?)
stack ends

data segment
data ends

code segment
    assume  cs:code, ds:data
start:
   ;  mov dx,43h
   ; mov al,0b7h
    ;out dx,al
   ; mov dx,42h
   ; mov al,
   ; out dx,al
 
   mov dx,63h
   mov al,82h
   out dx,al
 a:mov dx,61h
   in  al,dx
   mov dx,60h
   out dx,al
 jmp a
 code ends
 end start