Preventing CGA revisionist history

[Chuck Guzis]

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.

Cheers,
Chuck