Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!psuvax1!psuvm.bitnet!cunyvm!ndsuvm1.bitnet!nu140487
From: NU140487@NDSUVM1.BITNET (Me)
Newsgroups: comp.sys.amiga
Subject: TWO Denise's??
Message-ID: <2273NU140487@NDSUVM1>
Date: 19 May 89 02:36:30 GMT
Organization: North Dakota Higher Education Computer Network, Fargo, ND
Lines: 64
DISCLAIMER: Author bears full responsibility for contents of this article.


     Upon reading an article appearing in the FMAUG (Fargo-Moorhead Area User
Group) newsletter... i'm just curious as to how MUCH we Amiga users are in the
dark.
     The writer, who claims he had come across some material that had been
recovered from Jay Miner's "trash can", says basically that in a normal Amiga
setup, two of the Denise pins are listed as not connected. Yet they do serve
a purpose.
     The original Amiga motherboard design had space for several extra sockets,
of which were 'supposed' to be OS ROMS. But Jay's material shows that this is
not the case, and that one of the sockets was to hold a second Denise chip.
The Amiga, in it's "Dual-Denise" mode, was capable of many more graphics modes.
     First off, the DD mode would have doubled the horizontal resolution by
"doubling the frequency of the dot clock and interleaving the output of each
Denise." Apparently the only reason why it was never publically made known of
was it would have required the use of a Multisync monitor (which were pretty
expensive back then).
     In addition to doubling the horizontal resolution, a DD combo would also
allow for EXtenden HAM and EX mode. EXtended HAM would allow for HAM to be used
in hi-res mode (640X200 and 640X400)... and overscan as well. Also, instead of
a mere 16 colors, 256 colors are available. In lower resolution modes (320X200
and 320X400) the maximum number of colors is kicked up to 16,777,216 (the
article didn't say how many were available on screen at once). There is also
a "Landscape mode", which allows for a maximum resolution of 1280X400 (plus
overscan)... which for some reason is used when the monitor is placed on it's
side.
     Other possiblilities were mentioned as well. Using the Denise chip in
groups of four in a "piggy-back" configuration, much like Transputer processers
are networked, another video configuration is attained. (The article failed to
go into detail about this, but said that current video technology could not
possibly accommodate these modes.)
      Now, i'm not sure how accurate these accounts are... it's just something
that i've read like... 5 minutes ago. But knowing Jay Miner's ability
to perform miracles with stuff like this, i serioulsly wouldn't doubt it.
      This also brings up the question of where Commodore is taking the Amiga.
We all know that Commodore's   >ahem<... uh... "marketing" has just about
doomed the Amiga to a life of video game junkies ...etc etc...  but what about
it's developers? Now I know that these guys spend a >large< portion of their
lives to give us a good and well designed machines... but apparently (upon
looking at this article, and assuming it is valid) they were not debriefed
as to what could be possible with a little creative configurations. I hope
this is the case, 'cause if they knew about it's abilities... and just said
F***-it... and went and doomed the newer machines (the A500 and the A2000)
to an inability for these configs... then i will have lost all of the respect
and admiration I hold for the developers who have taken the Amiga under their
wings.
      Psst... say guys... I'd have no problem with going out and buying a
multi-sync >hint<... heck... i'd have to anyway if i wanted to use the ECS...
>nudge< ... geez, with 16,777,216 colors... i could make a heckuva neet-o
outdoor painting >wink<...            :-)

      Jason

  ... oh... and by the way... i've just found out today that i don't have an
ExtraHalfbright chip in my A1000. :-(   Could anyone tell me if it would be
possible to get a hold of one... and how much? The dealers downtown told me
to buy an A500 or A2000.     then i told them...        n
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