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fredericopissarra:

--- Quote from: Frank Kotler on November 18, 2020, 09:44:50 PM ---Untested! I think that's right. Holler if any problem or if you want to make a '.com' file out of it (model tiny).
--- End quote ---

Small changes made by me:


--- Code: ---; PROGRAM.ASM
;
; Compile:
;   nasm -f obj program.asm
;
; link program.obj (using Borland C++ 3.1 or Turbo C 2.1 linker)
;   tlink /n program.obj,program.exe
;
; OBS: DOS don't use '.section' names. The sectios are:
;   'stack', 'code' and 'data' (and 'bss' if it exists).
;
; OBS: I don't think Visual Studio's LINK can handle DOS
;      executables anymore.
;
; OBS: If you want to make sure to use only 8086 instructions,
;      you can use 'cpu 8086', otherwise 386 instructions will be
;      available to you in real mode.

  bits 16
  ;cpu 8086    ; uncomment to make sure 8086 instructions only.

; -------- STACK for the EXE process.
  section stack stack ; first "stack" is name,second is attribute

  resb 256      ; 256 bytes stack (is enough for this small program).
stack_top equ $

; -------- OUR DATA segment
  section data data

Asterisks1 db `*****\r\n$`
Asterisks2 db `*   *\r\n$`

; -------- OUR CODE segment
  section code code

..start:

  ; Need to setup stack!
  mov   ax,stack
  mov   ss,ax
  mov   ax,stack_top
  mov   sp,ax

  mov   ax,data
  mov   ds,ax

  ; print top row.
  lea   dx,[Asterisks1]
  mov   ah,9
  int   0x21

  ; print 3 middle rows.
  mov   cx,3
.loop:
  lea   dx,[Asterisks2]
  mov   ah,9
  int   0x21
  dec   cx
  jnz   .loop

  ; print bottom row.
  lea   dx,[Asterisks1]
  mov   ah,9
  int   0x21

  ; exit(0)
  mov ax,0x4c00
  int 0x21
--- End code ---

Tested with NASM and TLINK (Borland C++ 3.1 or Turbo C 2.1) in DOSBOX.
NASM compilation on Linux... Linkage on DOSBOX.

Frank Kotler:
Thanks Debs

Thanks Frederico

Many eyes make fewer bugs!

Best,
Frank

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