Preventing CGA revisionist history
cclist at sydex.com
Wed Jan 18 20:31:56 CST 2006
On 1/18/2006 at 5:08 PM ard at p850ug1.demon.co.uk wrote:
>I doubt it. I seem to rememebr a PROM in the input stages of the 5154
>monitor, which may well have done the same conversion, though.
Darn--you're right. On page 4 of the EGA display tech ref, there's a table
that says "When operating in Mode 1, the display maps the 4 input bits into
16 of the possible 64 colors as shown in the following table" While bright
yellow (color 14) is given as RrGgb, color 6 is given as Rg (brown),
where dark yellow would be RG. How very strange to special-case it in the
monitor! Probably done because the EGA could drive a CGA monitor and
that already had the brown special-casing.
I'm not inclined to check the PGA BIOS, but the PGA display appears not to
do the color re-mapping.
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