Path: utzoo!mnetor!uunet!husc6!mit-eddie!ll-xn!ames!pasteur!ucbvax!hoser.berkeley.edu!bryce
From: bryce@hoser.berkeley.edu (Bryce Nesbitt)
Newsgroups: comp.sys.amiga
Subject: Re: A2000 PC-AT slots, and 'Fatso' Agnes
Message-ID: <22691@ucbvax.BERKELEY.EDU>
Date: 21 Jan 88 03:48:35 GMT
References: <4230011@hpfclq.HP.COM>
Sender: usenet@ucbvax.BERKELEY.EDU
Reply-To: bryce@hoser.berkeley.edu (Bryce Nesbitt)
Organization: The Logic Foundation
Lines: 46

In article <4230011@hpfclq.HP.COM> cunniff@hpfclq.HP.COM (Ross Cunniff) writes:
|Question 1:	...it will soon become desirable to transform the last two PC
|slots on the A2000 into PC-AT slots....

Just solder the new connectors in.  Nothing else needed.


>Question 2: [I've heard some rummors...]
>1.  Allow for 400 line non-interlaced displays
>    (on a multi-scan type monitor)

Great rummor!  I hope it is true.  200 line displays are ugly... square
pixels are worth the hassle.  Here's an even better rummor... a
1280*800 pixel mode.  This does not even require any higher raw memory
bandwidth (for monochrome).


>Any ideas how an Agnes/Denise/Paula
>replacement could create a 640x400x8 noninterlaced
>screen WITHOUT requiring a significantly faster
>bus and RAM chips? 

Yes.  Double with width of the bus.  If you look at the way the chips
are structured, you see that Agnus only generates addresses.  The
actual data does not need to pass thorough it.

This means it would be possible (not easy, or trivial, just possible)
to do a 32 bit Denise.  All your registers, etc. would still remain
16 bits wide.  This would cut in half the memory time slots needed
for any one display.  It would still leave a 16 bit blitter, but
that blitter would have twice the free cycles to operate with.


>If not, I'll just have to dismiss these
>rumors as entirely bogus, as such changes would probably
>require MAJOR motherboard rework.

But the bogus rumors are the most fun.  Just read Atari press releases
for some prime examples :-) :-)!  (Or Commodore ones for that matter...
where's my Commodore LCD?)

|\ /|  . Ack! (NAK, SOH, EOT)
{o O} . bryce@hoser.berkeley.EDU -or- ucbvax!hoser!bryce (or try "cogsci")
 (")
  U	"As an engineer, I only set the value of a product... not the cost."
	-Bryce Nesbitt