Article View: comp.sys.amiga.tech
Article #11546Re: Longword alignment with 68020
From: Scott Henry
Date: Tue, 21 Feb 1989 21:35
Date: Tue, 21 Feb 1989 21:35
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1475 bytes
From article <6031@cbmvax.UUCP>, by daveh@cbmvax.UUCP (Dave Haynie):
>
> No, actually, the 68020 is less demanding about word alignment than the
> 68000. It wants instructions word aligned, but data doesn't have to be
> aligned at all. However, if a longword datum isn't longword aligned, the
> '020 will take two cycles to get at it, which will of course make fetching
> that thing 1/2 as fast as it could be.
Does this mean that the 68020 will work with byte-aligned word and longword
data? That's the only interpretation of "less demanding" that fits this
context. No more odd-address traps on data? :-)? Is this, then another
potential incompatibility with the 680?0 series?
> --
> Dave Haynie "The 32 Bit Guy" Commodore-Amiga "The Crew That Never Rests"
> {uunet|pyramid|rutgers}!cbmvax!daveh PLINK: D-DAVE H BIX: hazy
> Amiga -- It's not just a job, it's an obsession
--
---------------------
Scott Henry <scotth@sgi.com>
#include <std_disclaimer.h>
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arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!decwrl!sgi!scotth@harlie.SGI.COMReferences:
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!decwrl!sgi!scotth@harlie.SGI.COM From: scotth@harlie.SGI.COM (Scott Henry) Newsgroups: comp.sys.amiga.tech Subject: Re: Longword alignment with 68020 Message-ID: <27183@sgi.SGI.COM> Date: 21 Feb 89 21:35:41 GMT References: <6031@cbmvax.UUCP> Sender: daemon@sgi.SGI.COM Distribution: na Organization: Silicon Graphics, Inc., Mountain View, CA Lines: 21