Re: IIgs Analog Video Circuitry

[Kevin Dady <kevin@hackaday.com>]

On Sep 30, 1:23 pm, Daniel Kruszyna <d...@krue.net> wrote:
> Kevin Dady <ke...@hackaday.com> wrote:
> > its probably some form of summer, you generally cant take a bunch of voltages
> > and simply wire them together and expect them to work (correctly), and yes if
> > its a epoxy blob sip IC chances are its custom, even if its not good luck
> > finding it unless its a scavenged / nos part...
>
> > Is yours broken?
>
> Fortunately no, my IIgses are all working fine. My main reason for asking is
> that I'd like to output to an AppleColor RGB monitor for a project I'm working
> on. I thought that copying the IIgs video output circuitry would be an easy way
> to do so.
>
> Another option I'm looking at is this chip:
>
> http://www.analog.com/en/audiovideo-products/video-encoders/adv7123/p...
>
> It looks like I'd still need to generate the composite sync separately though,
> since this chip only provides the rgb signals.
>
> -- Daniel

I have never even seen a IIGS in person (I know I know) so I am just
stabbing in the dark, do you have any idea what of what timing that
monitor is expecting? I would guess its much faster than what the GS
is putting out (somewhere close to VGA?) and that starts to get pretty
tricky (though if you feel the need to blow a small pile of money
there are scan converters available)