13 Oct
2006
13 Oct
'06
2:22 p.m.
Bob wrote:
On Fri, 13 Oct 2006 13:43:42 +0000, Jules Richardson
wrote:
Correct.
That's interesting, though. IBM must have
believed that the 5150 would be a
global product and I'd expect that was the plan all along - so why put
circuitry on there for one market only?
I do not think there was ever was a PAL version of the CGA card. As far as I know the CGA card was the only one
dependant on the base clock freq being right on.
or It would loose color burst. I always thought the 4.77mhz was chosen because it could
also be used as the
clock ref for the video.
Yep. The fact that it and the CPU are driven at integral divisions of
the timer rate is further proof.
--
Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/
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