how do I connect a BBC micro to a VGA monitor?

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Sat Jan 31 19:56:22 2004

>
> I would like to connect the RGB TTL output of a BBC micro to
> a VGA monitor, does anybody have any pointers - suggestions?

It's very difficult...

The trivial problem is that he RGB socket on a Beeb is TTL level digital,
the VGA input is analogue. Trivial, because there's only 1 bit per colour
on the Beeb anyway, so a resistor network will convert the voltage levels.

The difficult problem is that the scan rates are totally different (VGA
is 31kHz horizontal, the Beeb is 15.625kHz). If you have a multisync
monitor that will go down to 15kHz (some of the old ones will), then
there's no problem, otherwise you've got a lot of work either modifying
the monitor or making a standards converter.

Probably the easiest solution if you're not a video expert is to use a PC
with a TV input card. You could at least feed the Beeb's composite output
into such a card (do any such cards exist with RGB inputs?)

-tony
Received on Sat Jan 31 2004 - 19:56:22 GMT