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Re: Need example of IIgs code to set BRK vector

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On 1/2/2012 8:55 PM, datawiz wrote:
> Can anyone offer a snippet of assembly code to properly set the BRK
> vector on the IIgs?
>
> I'm working on fixing a couple more Apple II games that don't work on
> the IIgs, and I've noticed a trend of BRK causing problems. In the
> latest case, the Apple II BRK vector at FFFE/FFFF is set to point to
> user space code and it's used extensively as a method of code
> obfuscation by the copy protector. In previous fixes, it's been a
> single BRK event, which can be patched to jump to the exit point. In
> this case, BRK instructions are littered throughout the code and sent
> to it's internal handler, so I can't patch every instance and a
> complete rewrite is a bit daunting.
>
> So the path of least resistance seems to be to set the IIgs BRK vector
> to point to the same Apple II BRK vector and it should work correctly,
> right?
>
> I'm not a IIgs guy at all, so any assistance would be appreciated.
>
> Thanks!
> Rich

The IIgs actually has tools to set the BRK vector.  Here is a link to 
IIgs Technote #1 which includes sample source code:

http://www.1000bit.it/support/manuali/apple/technotes/iigs/tn.iigs.001.html

Charlie

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Need example of IIgs code to set BRK vector datawiz <rich.martin@gmail.com> - 2012-01-02 17:55 -0800
  Re: Need example of IIgs code to set BRK vector Charlie <charlieDOTd@verEYEzon.net> - 2012-01-02 22:32 -0500
    Re: Need example of IIgs code to set BRK vector datawiz <rich.martin@gmail.com> - 2012-01-02 20:01 -0800
      Re: Need example of IIgs code to set BRK vector Charlie <charlieDOTd@verEYEzon.net> - 2012-01-03 00:21 -0500
        Re: Need example of IIgs code to set BRK vector datawiz <rich.martin@gmail.com> - 2012-01-02 21:46 -0800
          Re: Need example of IIgs code to set BRK vector Charlie <charlieDOTd@verEYEzon.net> - 2012-01-03 15:10 -0500
            Re: Need example of IIgs code to set BRK vector datawiz <rich.martin@gmail.com> - 2012-01-03 13:56 -0800
  Re: Need example of IIgs code to set BRK vector "Anton Treuenfels" <teamtempest@yahoo.com> - 2012-01-03 20:17 -0600
    Re: Need example of IIgs code to set BRK vector datawiz <rich.martin@gmail.com> - 2012-01-04 06:55 -0800
      Re: Need example of IIgs code to set BRK vector datawiz <rich.martin@gmail.com> - 2012-01-04 07:10 -0800
        Re: Need example of IIgs code to set BRK vector magnusfalkirk <dean.phares@gmail.com> - 2012-01-04 09:05 -0800

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