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Re: XMS transfer troubles with Turbo C

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Mateusz Viste  <mateusz.viste@localhost> wrote:
>I also found an old XMS library, written by Michael Graff 
>(xmslbn17.zip), unfortunately it's entirely written in ASM, which I am 
>not very comfortable with. The library does, however, mention some Turbo 
>C specifics, and it seems to play with the BP register. I don't know 
>why, since BP is never mentioned in the XMS specification... any idea? 

The comment "use bp to address parameters" gives you a hint what it's
used for. It's used to access the parameters passed to the function,
specifically the MoveRec argument declared just after the proc statement.
The instruction "lds si,[MoveRec]" will be expanded to something like
"lds si,[bp+4]".

You pretty much have no alternative than using assembly code like this
to do the transfer.  You can't reliably change _DS in C code because
it's hard to predict when the C compiler will emit code that depends on
_DS pointing to the default data segment.

You might be able to do this using inline assembly, be sure to save and
restore the DS register inside a single asm statement.

						Ross Ridge

-- 
 l/  //	  Ross Ridge -- The Great HTMU
[oo][oo]  rridge@csclub.uwaterloo.ca
-()-/()/  http://www.csclub.uwaterloo.ca/~rridge/ 
 db  //	  

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XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-24 19:18 +0200
  Re: XMS transfer troubles with Turbo C Johann Klammer <klammerj@NOSPAM.a1.net> - 2014-07-24 22:00 +0200
    Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-25 08:12 +0200
  Re: XMS transfer troubles with Turbo C Ross Ridge <rridge@csclub.uwaterloo.ca> - 2014-07-25 15:54 -0400
    Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-26 16:34 +0200
      Re: XMS transfer troubles with Turbo C "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-07-26 13:21 -0400
        Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 09:57 +0200
          Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 10:38 +0200
            Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 11:01 +0200
              Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 11:20 +0200
                Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 12:07 +0200
                Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 12:41 +0200
                Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 15:46 +0200
                Re: XMS transfer troubles with Turbo C Johann Klammer <klammerj@NOSPAM.a1.net> - 2014-07-27 16:39 +0200
                Re: XMS transfer troubles with Turbo C Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 20:09 +0200
          Re: XMS transfer troubles with Turbo C "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-07-27 12:32 -0400
            Re: XMS transfer troubles when AWEUTIL is loaded (exception 0D) Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 20:23 +0200
      Re: XMS transfer troubles with Turbo C Ross Ridge <rridge@csclub.uwaterloo.ca> - 2014-07-27 12:25 -0400
        Re: XMS transfer troubles when AWEUTIL is loaded (exception 0D) Mateusz Viste <mateusz.viste@localhost> - 2014-07-27 20:05 +0200
          Re: XMS transfer troubles when AWEUTIL is loaded (exception 0D) "Alexei A. Frounze" <alexfrunews@gmail.com> - 2014-07-28 22:13 -0700
            Re: XMS transfer troubles when AWEUTIL is loaded (exception 0D) rugxulo@gmail.com - 2014-07-29 15:08 -0700
              Re: XMS transfer troubles when AWEUTIL is loaded (exception 0D) Mateusz Viste <mateusz.viste@localhost> - 2014-07-30 08:25 +0200
  Re: XMS transfer troubles Mateusz Viste <mateusz.viste@localhost> - 2014-07-28 21:10 +0200

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