prog6_9.asm

汇编语言-王爽 源代码 加 卜艳萍版源代码

stack  segment para stack 'stack'
       db  256 dup(?)
stack  ends
data  segment
str   db 'please input 1,2,3,4:','$'
str1  db 'branch1','$'
str2  db 'branch2','$'
str3  db 'branch3','$'
str4  db 'branch4','$'
err   db 'error','$'
data ends
code  segment
      assume  cs:code,ds:data,ss:stack
start:mov  ax,data
      mov  ds,ax
begin:;mov dx,seg str
      ;mov ds,dx
      mov dx,offset str
      mov ah,9h
      int 21h 
      mov  ah,01h
      int  21h
      cmp  al,31h
      je  a1
      cmp  al,32h
      je  a2
      cmp  al,33h
      je  a3
      cmp  al,34h
      je  a4
      mov  dx,offset err
      mov  ah,9
      int  21h
      jmp  finish
   a1:mov  dl,0dh
      mov  ah,2
      int  21h
      mov  dl,0ah
      int  21h
      mov  dx,offset str1
      mov  ah,9
      int 21h
      jmp  enter
   a2:mov  dx,offset str2
      mov  ah,9
      int  21h
      jmp  enter
   a3:mov  dx,offset str3
      mov  ah,9
      int  21h
      jmp enter
   a4:mov  dx,offset str4
      mov  ah,9
      int  21h
enter:mov  dl,0dh
      mov  ah,2
      int  21h
      mov  dl,0ah
      int  21h
      jmp  begin
finish:mov  ah,4ch
      int  21h
code  ends
      end start