10.asm

华工电信系汇编习题的编程实现

stack segment stack 'stack'
      dw 32 dup(?)
stack ends

data segment
     N db ?
     outbuf db 'Please input The Number(1~4):$'   
     WA dw 0F12AH
     BA db 12H
data ends

code segment
begin proc far
      assume  ss:stack,cs:code,ds:data
      push ds
      sub ax,ax
      push ax
      mov ax,data
      mov ds,ax
  
      mov dx,offset outbuf
      mov ah,9
      int 21h

      mov ah,1
      int 21h;
      sub al,30H
      mov N,al;
      
      mov ax,offset WA                 
      mov cl,2
      shl N,cl
      sub N,4            
      mov cl,N ;N -1 de 4 bei
      shr WA,cl
      and byte ptr WA,0FH
      mov al,BA
      and al,0F0H
      add al,byte ptr WA 
      mov BA,al

      ret
begin endp
code  ends
      end begin