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From: bobb@vice.ICO.TEK.COM (Bob Beauchaine)
Newsgroups: comp.lang.pascal
Subject: Re: INT 25h problem
Summary: Int 25 code
Message-ID: <6860@vice.ICO.TEK.COM>
Date: 6 Feb 91 20:24:11 GMT
References: <25848@adm.brl.mil>
Reply-To: bobb@vice.ICO.TEK.COM (Bob Beauchaine)
Organization: Tektronix, Inc., Beaverton,  OR.
Lines: 57

In article <25848@adm.brl.mil> C0361@univscvm.csd.scarolina.edu ( Thomas Jenkins) writes:
>Hi,
>
>  Seems to me the problem is best handled with Inline, linked in assembly or
>the ASM block in TP 6.0 .  Since the flags are left on the stack after the
>call, using Intr will never work. 

  The following is from _Turbo_Pascal_Advanced_Techniques_, by Chris Olsen
  and Gary Stoker, from the Que Programming Series, and is reproduced here
  without permission from the authors.

  *************************
  Procedure AbsRead(var buf; drive,number,logical : word);
  var 
    result : integer;
  begin
    inline(
      $55/		{ Push BP }
      $1E/		{ Push DS }
      $33/$C0/		{ Xor AX,AX }
      $89/$86/Result/	{ Mov Result,AX }
      $8A/$86/Drive/	{ Mov AL, Drive }
      $8B/$8E/Number/	{ Mov CX, Number }
      $8B/$96/Logical/	{ Mov DX, Logical }
      $C5/$9E/Buf/	{ Lds BX,Buf }
      $CD/$25/		{ Int $25 }
      $5B/		{ Pop BX }
      $1F/		{ Pos DS }
      $5D/		{ Pop BP }
      $73/$04/		{ Jnb Done }
      $89/$86/Result);	{ Mov Result,AX }
  end;

  Procedure AbsWrite(var buf; drive,number,logical : word);
  var 
    result : word;
  begin
    inline(
      $55/		{ Push BP }
      $1E/		{ Push DS }
      $33/$C0/		{ Xor AX,AX }
      $89/$86/Result/	{ Mov Result,AX }
      $8A/$86/Drive/	{ Mov AL,Drive }
      $8B/$8E/Number/	{ Mov CX,Number }
      $8B/$96/Logical/	{ Mov DX,Logical }
      $C5/$9E/Buf/	{ Lds BX,Buf }
      $CD/$26/		{ Int $26 }
      $5B/		{ Pop BX }
      $1F/		{ Pop DX }
      $5D/		{ Pop BP }
      $73/$04/		{ Jnb Done }
      $89/$86/Result);  { Mov Result,AX if error }
  end;
  ************************

  Bob Beauchaine
  bobb@vice.ICO.TEK.COM