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Re: Best LCD for IIGS



MdntTrain wrote:
On Nov 9, 9:24 am, Drew <GoggleD...@gmail.com> wrote:

<<The pause/blank screen when the converter switches res and my
monitor
tries to also sync is a little annoying, when booting my GS i never
see the Apple IIGS bit, just GS/OS loading.>>

Yeah, I find that annoying too..  I wondered if it's doing that in
response to the changing dot clocks coming the IIgs as video modes are
switched.. but as its dot sync to the 16mhz super hires mode is
imperfect, I'm actually not sure what it's doing.   It could just be
that the V+H syncs coming from the IIgs are interrupted during mode
changes, thus simply requiring the converter to relock onto the
15.7khz signal.

As you noted, the change in dot clock is a likely cause.  When the IIgs
switches to 16MHz (SHR) mode, the lock circuitry that was happy with
14.3MHz becomes unsatisfied, and so disables video and starts to hunt
for a new lock.  When it fails to do so, it settles on some sampling
frequency and re-enables video conversion.

-michael

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