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Re: Apple ///?



In article <5igjah$teu@uni.library.ucla.edu>,  <pubpc1@library.ucla.edu> wrote:
>How does the Apple III access more than 64K without bank
>switching?  It uses a mere 6502B with a 16 bit memory
>address.

   It apparently doesn't switch full banks but lets you swap out
part(s?)  of main memory for some section of the extended memory.
Basically a far more intelligent, intuitive, easier to use, and
intelligent design than the 'bank switching' hacks of the //c and //e.

   The Apple III had a bunch of far better designed sections than the
later //e and such, but Apple got the wrong idea into their head that
the III's failure was due to its extra features [and not stuff like
hardware more flakey than the day-old bin at a pastry shop, and making
life difficult for programmers and users who wanted to do Apple II
stuff], so they made the //e not that much more than the ][+.

   If they'd put the good features of the III in the //e, without
sacrificing stability, things would have been much nicer. They were
already doing custom VLSIs for the MMU and the like, and it could
have been done.

Nathan Mates
--
<*> Nathan Mates http://www.visi.com/~nathan/      <*>
# What are the facts? Again and again and again-- what are the _facts_?
# Shun wishful thinking, avoid opinion, care not what the neighbors
# think-- what are the facts, and to how many decimal places?  -R.A. Heinlein