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Re: Crosspost: Did the cpu influence the display?



Richard wrote:
[Please do not mail me a copy of your followup]

mjmahon@aol.com spake the secret code
<FoOdnWD5gdbjNijeRVn-pQ@comcast.com> thusly:


As Linards points out, the Apple ][ had color long before the
Commodore computers.  And it was able to do so without using any
more memory than for a monochrome display.  It's color is all
NTSC "artifact" color--an extremely clever design in 1977,
inspired by video games.


What's "artifact color"?

Color which is displayed as a result of a monitor's interpretation
of a pixel pattern which is synchronous with the color subcarrier
frequency.  It is often seen as false color appearing when a fine
vertical monochrome "grating" is shown on an NTSC monitor--like
a finely striped tie, shirt, or coat.

Several machines harness this effect to produce color displays.

It can also be envisioned simply as a digital synthesis of a
combined chrominance/luminance composite video signal, but the
usually very simple combination of patterns of fixed-width,
bi-level pulses at a multiple of the subcarrier frequency, in
which the pallette of colors have simple phase relationships,
is normally described as "artifact" color.

-michael

Music synthesis for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

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