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Re: Amiga, Mac, Atari

Hi,

  > Motorola created the 6800. A few designers walked out the door
  >with the masks to it and started a company called MOS Technologies
  >and made a chip called the 6500....

While that sure explains why the 65xx family are bus compatible with the
68xx family, I thought it was Chuck Peddle who designed the 6502 processor?

Also, from an architectural/software point of view I don't see any real
similarities between the 65xx and 68xx families.

After all, the 6502 has a pair of 8-bit index registers (X and Y) and an
8-bit accumulator (A). The 6800 has a single 16-bit(?) index register (X)
and a pair of 8-bit accumulators (A and B) which could be used together to
form a 16-bit accumulator.

This affects so many things at such a basic level that I cannot believe that
MOS could have used the 6800 masks for anything other than a basis to design
a completely new product from, IE they just used them to see how it was
done.


  TTFN - Pete.