task1__6_6.1/main.asm

   1 ;
   2 ; Copyright (C) 2008  Alexander Potashev
   3 ;
   4 ; Exchange of 2 top words in the stack, all registers saved
   5 ;
   6
   7 .model small
   8 .code
   9
  10 start:
  11         push 10
  12         push 20
  13         push 30
  14         push 40
  15         push 50
  16         push 60
  17         push 70
  18         push 80
  19         push 90         ; [bp + 6]
  20         push 100        ; [bp + 4]
  21
  22 ;-----------------------
  23         push ax         ; save all registers which will be used
  24         push bp
  25
  26         mov bp, sp      ; using "bp" to access stack variables
  27
  28         mov ax, [bp + 4]        ; exchange
  29         xchg ax, [bp + 6]
  30         mov [bp + 4], ax
  31
  32         pop bp          ; restore registers
  33         pop ax
  34 ;-----------------------
  35
  36         add sp, 20
  37
  38         mov ax, 4c00h
  39         int 21h
  40
  41 .stack 256
  42
  43 end start
  44