[Coco] VDG weirdness

[chawks at dls.net]

Yeah, but what a pony!!

Christopher R. Hawks
--
....Unix, MS-DOS, and Windows NT (also known as the Good, the Bad, and
the Ugly).


On Tue 10/20/15 12:42 PM , "John W. Linville" linville at tuxdriver.com sent:
> Yeah, I'm a one-trick pony... ;-)
> 
> On Tue, Oct 20, 2015 at 11:21:02AM -0500, Zippster wrote:
> > No, just a badly thought out guess… 
> > I realized what it probably was right after
> sending.  :)> 
> > - Ed
> > 
> > 
> > > On Oct 20, 2015, at 11:15 AM, Brian Blake
>  m.rodder at gmail.com> wrote:> > 
> > > I doubt it's that, it's CoCo 3 and doesn't
> use artifacts.> > 
> > > Since it's John's post, I'd guess
> Fahrfall...> > 
> > > Of course if your comment was in jest, I
> completely missed it... ;)> > 
> > > 
> > > 
> > > Brian
> > > 
> > > 
> > > On 10/20/2015 11:52 AM, Zippster
> wrote:> >> Ooooh…  Nice.   Sock
> Master’s Donkey Kong, maybe?> >> 
> > >> - Ed
> > >> 
> > >>> On Oct 20, 2015, at 9:47 AM, John
> W. Linville  le at tuxdriver.com> wrote:> >>> 
> > >>> NTSC artifacts are an important
> consideration, for sure.  FWIW, what> >>> I had in mind would be to put a
> certain CoCo game in a traditional> >>> arcade cabinet (with 15kHz RGB
> video).  In that case, whether or not> >>> the NTSC artifacts matter becomes
> game dependent... :-)> >>> 
> > >>> John
> > >>> 
> > >>> On Mon, Oct 19, 2015 at 05:53:48PM
> -0500, Zippster wrote:> >>>> This is very similar to a board
> I was developing when Brendan approached me> >>>> with his FPGA based project,
> which I stopped development on in favor of pursuing> >>>> the FPGA solution.
> > >>>> 
> > >>>> The only major drawback for
> NTSC machines would be the lack of artifacts for CoCo1/2 games,> >>>> but an
AD725 or similar could
> be added to generate high quality composite that might> >>>> get them back on a
secondary
> output.  Of course that doesn’t matter for PAL.> >>>> 
> > >>>> Very nice! :)
> > >>>> 
> > >>>> - Ed
> > >>>> 
> > >>>> 
> > >>>>> On Oct 19, 2015, at 5:42
> PM, Phill Harvey-Smith  h.org.uk> wrote:> >>>>> 
> > >>>>> On 19/10/2015 22:40, John
> W. Linville wrote:> >>>>>> That's pretty cool,
> Phill!  After seeing the old Atom color boards> >>>>>> I had thought to do a
> similar project at some point.> >>>>>> 
> > >>>>>> Do you have any plans
> to market such a board?> >>>>> Well I'm thinking about it
> but got a couple of other projects on the go at the mo. And it's kinda
> still in development because of the PAL / NTSC thing.> >>>>> 
> > >>>>> Basically I'm maybe going
> to implement the PAL additional line logic in the CPLD so that it just
> relies on the VDG clock output by the SAM (and disconnects the 6847's VDG
> clock from any circuitry on the motherboard).> >>>>> 
> > >>>>> This should make it
> independent of the various different models of both the CoCo and Dragon
> motherboards, and as a side effect should enable a machine to run at either
> frame rate (if I get it right).> >>>>> 
> > >>>>> Cheers.
> > >>>>> 
> > >>>>> Phill.
> > >>>>> 
> > >>>>> -- 
> > >>>>> Phill Harvey-Smith,
> Programmer, Hardware hacker, and general eccentric !> >>>>> 
> > >>>>> "You can twist
> perceptions, but reality won't budge" -- Rush.> >>>>> 
> > >>>>> -- 
> > >>>>> Coco mailing
> list> >>>>> Coco at mal
> tedmedia.com> >>>>> https://pairlist5.pair.net/mailman/listinfo/coco> >>>> 
> > >>>> -- 
> > >>>> Coco mailing list
> > >>>> Coco at mal
> tedmedia.com> >>>> https://pairlist5.pair.net/mailman/listinfo/coco> >>> -- 
> > >>> John W. Linville		Someday the world
> will need a hero, and you> >>> linvil
> le at tuxdriver.com			might be all we have.  Be ready.> >>> 
> > >>> -- 
> > >>> Coco mailing list
> > >>> Coco at mal
> tedmedia.com> >>> https://pairlist5.pair.net/mailman/listinfo/coco> >> 
> > > 
> > > 
> > > -- 
> > >
> ------------------------------------------------------------------------> >
Tandy Color Computer > > Tandy CoCo Forum
> > 
> > > -- 
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> > > Coco at mal
> tedmedia.com> > https://pairlist5.pair.net/mailman/listinfo/coco> 
> > 
> > -- 
> > Coco mailing list
> > Coco at mal
> tedmedia.com> https://pairlist5.pair.net/mailman/listinfo/coco
> -- 
> John W. Linville		Someday the world will need a hero, and you
> linvil
> le at tuxdriver.com			might be all we have.  Be ready.
> -- 
> Coco mailing list
> Coco at mal
> tedmedia.comhttps://pairlist5.pair.net/mailman/listinfo/coco
> 
>