IIgs video modes...

["Michael J. Mahon" <mjmahon@aol.com>]

I apparently don't have a IIgs schematic, so I'd like to ask about
video generation on the IIgs.  (Wouldn't it be great to have an
"Understanding the Apple IIgs"?)

The traditional (non-IIgs) video modes all fit their video into
a 40-cycle "window", based on a 140-/280-/560-pixel width, and have
a video dot clock of 7MHz or 14MHz.

The IIgs introduces the SHR modes, which have 320- and 640-pixel
widths.

Is the display "window" for the SHR modes still 40 microseconds
wide--implying a different pixel rate--or does the "border" shrink
for the SHR modes to allow room for more pixels at the same rate(s)?

-michael

NadaNet networking for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."