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Re: Need example of IIgs code to set BRK vector

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On 1/2/2012 11:01 PM, datawiz wrote:
> Thanks Charlie, I saw that earlier.
>
> What do the standard macros for
> _GetVector
> _SetVector
> assemble to?

All tools can be called from assembly by loading the X register with the 
toolset number in the high byte and the tool number in the low byte and 
then doing a JSL $E10000.  JSL is a long JSR.  For _GetVector you would do:

LDX #$1103
JSR $E10000

and

_SetVector would be:

LDX #$1003
JSL $E10000

But the thing is you have to start the toolsets before you can use them 
and some toolsets are dependent on others, etc, etc.

> I don't have a IIgs development environment set up. Can the IIgs mini-
> assembler understand those macro calls?

No.

> Sorry, I have absolutely no IIgs programming experience, so I'm pretty
> much a newb. :)

Okay, so doing it with tools is not really an option.  Are you sure that 
the BRK vector is the problem?  Are you booting a game disk on the IIgs 
or are you running a game program from GS/OS?

It's been a long, long time since I did any IIgs programming but I 
thought that GS/OS sets its BRK vector at $E10070-73 and I thought when 
you booted an 8 bit OS that it went with the old $03F0-$03F1 pointing to 
$FA59.  Someone correct me if I'm wrong.

Charlie


> On Jan 2, 10:32 pm, Charlie<charlieD...@verEYEzon.net>  wrote:
>> 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.00...
>>
>> Charlie
>

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Thread

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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