28 Nov
2007
28 Nov
'07
3:55 p.m.
mbbrutman-cctalk at brutman.com wrote:
I mistook an IBM Industrial CGA display for a
monochrome display, and
plugged it into a monochrome display adapter port. There was no smoke
or funny noises, but it definitely did not work.
I've heard stories about the IBM monochrome displays being fragile when
mishandled like this. Were the IBM CGA displays also this fragile?
(I won't be able to test it until I dig out a CGA card. And now of
course I'm just paranoid and hoping that I didn't hurt it.)
CGA is 15.75KHz H and 60Hz V; monochrome is 18.4KHz H and 50Hz V.
That's pretty similar bandwidth, and I haven't heard any stories nor
personally experienced that doing what you did would release the magic
smoke. If you didn't hear a loud high-pitched whine, or smell ozone, I
wouldn't worry about it.
I *have* witnessed a monochrome monitor releasing the magic smoke
through software, but the software in question was something that fed
random values to all of the MDA ports in rapid succession. Who knows
what kind of timings (or pulses!) were responsible for blowing it up...
--
Jim Leonard (trixter at oldskool.org) http://www.oldskool.org/
Help our electronic games project: http://www.mobygames.com/
Or check out some trippy MindCandy at http://www.mindcandydvd.com/
A child borne of the home computer wars: http://trixter.wordpress.com/