General public machines (Was: Altair 8800 name Was: Re: Altair 680 Expansion Boards?

Cameron Kaiser spectre at
Fri Dec 23 23:29:01 CST 2016

> > Commodore's Z80 in the 128 was due to unnecessary fear that they might lose 
> > market share to CP/M, when IBM should have been their big worry.
> > I don't know all of the details of the ST/Amiga technology swap, but BOTH 
> > were too late, if the primary goal was competing with IBM.
> That might be Commodore marketing - Bil Herd said that he threw the Z-80 
> into the design essentially because he could. :)  He's done a few talks on 
> how the C-128 came about.  It's pretty interesting.

It also saved the 100% compatibility problem (in this case, with Commodore's
CP/M cartridge by designing it onto the board, and with Commodore Magic Voice,
which fouled banking by altering the memory configuration lines in realtime:
the 8502 would crash, but the Z80's activity would not be detected and the
C= key could be checked to force a C64 memory map).

------------------------------------ personal: --
  Cameron Kaiser * Floodgap Systems * * ckaiser at
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