Re: One-on-one on IIgs

[a2@wilserv.com (Willi Kusche)]

Hi!

"Greg Andrzejewski" <pressyourluck85@yahoo.com> wrote in message news:<JpmdnUjsL5qmI9fdRVn-gQ@comcast.com>...
> Or is this just one Apple II program that will not work
> on a IIgs?

    The game, when it runs, utilizes machine language operation code
$54.  This op code is an undocumented op code on the 65C02 but is a
legal op code on the 65816.  So, it will not run on a IIgs.

    I discovered this while attempting to find out why the game would
not run on the Apple2000 emulator for the Amiga.  I came up with a fix
for Apple2000 and, at this very moment, am checking to see if the fix
made it into a version of Apple2000 that's available for downloading
on the I'net.

    I'm looking at a listing of the emulator and it would seem that
replacing the $54 op code with a NOP will allow the game to run on a
IIgs.  But I'm fairly certain that I have no record of exactly where
in the OneOnOne that op code is.

    More later in comp.emulators.apple2...

Willi