Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!rutgers!cbmvax!daveh
From: daveh@cbmvax.commodore.com (Dave Haynie)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Static vs. static column vs. dynamic vs. ???
Message-ID: <15764@cbmvax.commodore.com>
Date: 9 Nov 90 18:03:26 GMT
References: <15571@brahms.udel.edu> <1990Nov08.222823.1925@hoss.unl.edu> <1990Nov9.075535.14012@ncsuvx.ncsu.edu>
Reply-To: daveh@cbmvax.commodore.com (Dave Haynie)
Distribution: na
Organization: Commodore, West Chester, PA
Lines: 22

In article <1990Nov9.075535.14012@ncsuvx.ncsu.edu> kdarling@hobbes.ncsu.edu (Kevin Darling) writes:

>The A3K can use either paged or column.  But while Static Column can be a
>tiny bit faster, my home timing analysis indicated that it wouldn't make
>any diff which one you used on the 3000.  

The main advantage of using static column over page mode RAM is that, with
static column, you don't need to drive CAS*.  So everything can be address
driven, and there's no need for any additional CAS* state logic.  I didn't
do the Ramsey design myself, but Greg's claim is that there isn't quite
enough time to build this special CAS*, at least based on the grain of the
clocks used in Ramsey.  But with SCRAM, it's no problem, you simply change
addresses and keep CS* low.  So, for an A3000 with SCRAM in it, we allow the
68030 burst cycles to be run, but they won't work with fast page mode.

> Kevin Darling - "This is your  |  CIS: 76703,4227     Delphi:OS9ugpres


-- 
Dave Haynie Commodore-Amiga (Amiga 3000) "The Crew That Never Rests"
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	Standing on the shoulders of giants leaves me cold	-REM