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Re: IIgs video modes...



Linards Ticmanis wrote:
Michael J. Mahon wrote:


In the personal computing world of the early 1980s, there were two
video "camps":  those who used the artifact color trick and those
who didn't.  One glance at the master clock frequency was usually
enough to tell the difference.  ;-)


Hmmm... Commodores use a 14.31818 MHz main quartz too (the NTSC
versions, that is). Their pixel clock is quartz frequency divided by 7,
then multiplied by 4.

But did they also use the 14MHz clock divided by 4 for the chroma
subcarrier frequency?  In that case, they just saved having to add
a 3.58MHz crystal for the chroma modulator.  I suppose that saved
a fraction of a dollar.

There is also the fact that a 14.31818MHz crystal is a few cents
cheaper than another less popular nearby frequency...

-michael

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