Re: Alternate Display Mode?

[dempson@atlantis.actrix.gen.nz (David Empson)]

In article <3o4pdd$98h@gap.cco.caltech.edu>,
Nathan Mates <nathan@cco.caltech.edu> wrote:
> 
>    That's where the Alt Display Mode comes from. It sets up a
> background task to copy the page to the memory where it's displayed
> from so it looks right. If you must view this display area, it's a
> real useful tool. If you're like the 99% of us who never have any
> cause to use it, it's an extra entry in the CDA menu, and eats system
> time when on.

One point that you didn't mention: the above only applies with the
original IIgs (ROM 1).  The 1MB motherboard (ROM 3) has hardware
support for shadowing text page 2, which is usually turned off.  On
the ROM 3, turning on Alternate Display Mode simply changes the
hardware shadowing bit, and there is no speed penalty.
-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand