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Re: Looking for "Ultima II" .nib images



Andy McFadden wrote:
Linards Ticmanis <ticmanis@gmx.de> wrote:

Well "Ultima II" is a 1982 Sierra release. I doubt the copy protection schemes were all that great already in 1982. Nothing that Copy II+ shouldn't be able to handle, at least.


It has some sort of function -- possibly a nibble counter -- invoked
shortly after boot.  I remember cracking it.  It used two obfuscation
tricks: it did a branch into the middle of an instruction (a BIT $xxxx),
to conceal the start, then XORed itself before and after.  Once the
check was commented out it was easy to get a clean copy.

It's unlikely you'll get a simple .NIB image to work, but it's probably
a one-byte patch to fix it.

Sounds right.  I was musing to myself about just when nibble counting
entered the picture...

-michael

Music synthesis for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

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