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Re: The apple 2, the PC, and the clones

"Paul Grammens" <grammens@svn.net> writes:
>Yes, I also found this very interesting and educational. I didn't know the
>details of why IBM clones were legal but Apple clones generally weren't. I
>thought IBM facilitated the cloning.

The problem with cloning the Apple // firmware is that there are no INT
vectors - all the monitor routines are at fixed addresses. This makes it
difficult to replicate without using the same instructions. Had the monitor
been written with a jump table at the front it would have taken up more space
and been more easily cloned.
--
David Wilson  School of IT & CS, Uni of Wollongong, Australia