[linux-elitists] Hm, editor wars

Paul J Collins sneakums@eircom.net
Wed Jun 28 11:08:34 PDT 2000


>>>>> "Marc" == Marc MERLIN <marc@merlins.org> writes:

    Marc> On Tue, Jun 27, 2000 at 11:35:25AM -0700, Nick Moffitt wrote:
    >> begin  Marc MERLIN quotation:
    >> My Commodore 128 had two banks of 64k RAM.  You couldn't ever
    >> actually address it all at once, and had to waste several cycles
    >> switching banks.
 
    Marc> I know, I had a CPC 464 with a 64KB extension board. Same thing...

Acorn's BBC model B+ and  Master Series used a technique where the
video RAM was a separate 20K bank that was switched in by the OS
whenever it needed to draw on the screen.  I believe the shadow modes
were numbered x + 128, where x is the number of the actual mode.
Obviously nasty screen-scribbling apps did not work well with shadow
RAM at all...

And also on the B+ and Master Series, you could switch out the
memory-mapped I/O registers, and the ROM thus revealed contained a
list of all the people who worked on the machines' development.

Paul.

-- 
Paul Collins <sneakums@eircom.net> - - - - - [ A&P,a&f ]
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