29 Aug
2014
29 Aug
'14
1:03 p.m.
Some outfit made a monochrome monitor with a color jug
in it, so you
could manually select what color you wanted your display to use. Seems
a bit silly today, but there you go. IIRC, if you were driving a
I once used a colour EGA monitor which, along with the usual controls,
had a 3 position knob on the fornt, the positions being marked with
white, green and orange dots.
It selected how the whtie colour would appear (I can't remember what it
did to the other colours [1], it probably left them alone, certainly the
'green' position did not totally disable the red and blue electron guns).
Its main use was when dispalying white on black text, you could have the
equvialent of a grene creen or amber screen monitor.
[1] In common with most EGA monitors there was a little PROM inside that
took in the 6 bits of video data from the EGA card and drove trivial DACs
that fed the video amplfiiers. The programming of that PROM determined
the colour mapping. I am pretty sure the switch was just a couple mroe
address inputs to the PROM.
-tony