Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!ECNCDC.BITNET!MSRS002
From: MSRS002@ECNCDC.BITNET ("THE DOCTOR.")
Newsgroups: comp.lang.modula2
Subject: Logitech->JPI
Message-ID: <INFO-M2%89051917500273@UCF1VM>
Date: 19 May 89 21:47:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: Modula2 List <INFO-M2%UCF1VM.bitnet@jade.berkeley.edu>
Organization: The Internet
Lines: 37

Translating the graphics package should be pretty easy to do.
JPI includes all you need for interrupt calls, port manipulation
and manipulating memory.  I don't know Logitech at all, but
here's answers to questions 1-3.

I think you will have to recode all the interrupt calls.  The
module Lib has a procedure Intr, which is passed a data structure
( SYSTEM.Registers ), and an interrupt number.  Before the
interrupt is taken, it sets all the registers according to the
data structure.  When it returns, the data structure will reflect
the registers returned.  See page 165 of the TopSpeed User's
Manual.  Your code will look something like this:

   VAR
      R : SYSTEM.Registers ;

   BEGIN
      R.AH := ( whatever ) ;
      R.AL := ( something else ) ;
      R.CX := ( some 16 bit quantity ) ;
      ...  and so on ...
      Lib.Intr( R, 1CH ) ;
      ( you can now inspect R.whatever to see what happened )

Do you have the TopSpeed manuals?  I have modified their Graph
module to support EGA ( and therefore VGA ) a little better to
allow you to use the second page in graphic modes.  If you
already have it, I don't think they would mind me sending it to
you, even though I would be violating the copyright.

.

+---------------------+---------------------------------------+
   Tom Ruby              Any resemblance between reality and
   MSRS002@ECNCDC        my concept of reality is strictly
                         coincidental.
+---------------------+---------------------------------------+