Re: IIgs SVideo Mod Results

[MdntTrain <js@cimmeri.com>]

On Mar 16, 8:41 pm, Steven Hirsch <snhir...@gmail.com> wrote:
> MdntTrain wrote:
> > On Mar 16, 8:15 am, Linards Ticmanis <ticma...@gmx.de> wrote:
> >> MdntTrain wrote:
> >>>> They're claiming a 2-4 week backorder, so hopefully it won't drag out too long.
> >>> Who are you talking to there?
> >>>> I'll probably pick up one of those single-board converters for my C128, since it can easily be modified for RGBI.
> >>> What resolutions does the C128 put out?
> >> Its dot clock is exactly 16MHz for the 80 character screen.
>
> >> For the 40 character screen the dot clock uses frequencies derived from
> >> the color carrier. In NTSC, it is 8.181818... MHz (16/7 * color clock),
> >> in PAL it is 7.8819888... MHz (16/9 * color clock).
>
> >> --
> >> Linards Ticmanis
>
> > The other board that Steven is looking at then won't work.  The other
> > board is for arcade systems at much lower bandwidth.   My guess (based
> > on everything Mahon has taught me) is that all kinds of beat patterns
> > (aliasing bars) will show up at the C164's higher resolutions... which
> > appear close enough to the problematic IIgs modes I witnessed.
>
> There are no higher resolutions, AFAIK.  Also, there are many folks out there
> reporting success with the RGB board.  A fellow in Australia came up with the
> mode for the intensity line and sold a couple of dozen modded boards to folks
> in the US.  I've heard nothing about problems other than one of the possible
> CGA colors not quite matching what the Commodore display showed (dark yellow
> vs. brown or some such thing).- Hide quoted text -
>
> - Show quoted text -

We must be talking about different boards.. or I forgot something.
The board I experimented with was analog RGB -> VGA.. and you're
talking digital.   Maybe the board does both.  But the analog board or
portion of the board could not successfully handle (and was never
designed to handle) an 8 or 16mhz dot clock... just standard TV rates
per arcade game.

 JS