.model small
.code
org 100h
COUNT equ 1
start:

  mov al, 0							; Device Num (0-A, 1-B, ..)
  lea bx, _buf						; Buffer
  mov cx, COUNT		       			; Count
  mov dx, 1							; Number
  INT 25H
  pop dx 

  jc  error

  mov ah, 3ch
  lea dx, _fname
  mov cx, 0
  int 21h

  mov bx, ax
  mov ah, 40h
  mov cx, COUNT*200h
  lea dx, _buf
  int 21h

  mov ah, 3eh
  int 21h

  jmp exit

error:
  mov dl, ah  
  mov cl, al
  mov ah, 2
  int 21h

  mov dl, cl
  int 21h

  mov ah, 9
  lea dx, _err
  int 21h

exit:  
  mov ah, 4ch
  int 21h
_err db ' Fuck, some error',10,13,'$'
_fname db 'dump3.dat',0
_buf db 200h*COUNT dup (?)
end start