Article View: comp.sys.amiga.tech
Article #11551Re: Longword alignment with 68020
From: Leo 'Bols Ewhac' Schwab
Date: Wed, 22 Feb 1989 10:07
Date: Wed, 22 Feb 1989 10:07
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1570 bytes
In article <712@cord.UUCP> nsw@cord.UUCP (Neil Weinstock) writes:
>Do the 68020/32-bit memory boards (ala A2620) require that longword data
>be longword-aligned? [ ... ]
>
No. You will achieve optimum performance if you do align your
logwords/pointers on longword boundaries, but you'll still be able to fetch
longwords on arbitrary word boundaries.
As an extra added bonus, the '020 will read and write words on odd
*byte* boundaries (but you pay a heavy performance penalty). An entire
class of Gurus almost disappears! (Type 00000003, Address error.)
>(The blitter requires its data word-aligned, right? That has been my
>experience.)
>
Yes.
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Leo L. Schwab -- The Guy in The Cape INET: well!ewhac@ucbvax.Berkeley.EDU
\_ -_ Recumbent Bikes: UUCP: pacbell > !{well,unicom}!ewhac
O----^o The Only Way To Fly. hplabs / (pronounced "AE-wack")
"Work FOR? I don't work FOR anybody! I'm just having fun." -- The Doctor
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ames!think!bloom-beacon!apple!well!ewhac From: ewhac@well.UUCP (Leo 'Bols Ewhac' Schwab) Newsgroups: comp.sys.amiga.tech Subject: Re: Longword alignment with 68020 Message-ID: <10803@well.UUCP> Date: 22 Feb 89 10:07:25 GMT References: <712@cord.UUCP> Reply-To: ewhac@well.UUCP (Leo 'Bols Ewhac' Schwab) Distribution: na Organization: n. 1. The act or process of organizing. Lines: 22 Quote: "I'm not wearing any pants... Film at eleven." -- Kentucky Fried Movie