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Article #1464Re: 68000 Memory Managment
From: Wen-King Su
Date: Fri, 29 Aug 1986 23:45
Date: Fri, 29 Aug 1986 23:45
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<<->> This is only a note on John Bass's article about a way to do virtual memory with little or no extra cost in time. There is a catch to hiding MMU operations between RAS and CAS, though I do not know whether this applies to the ST. The high speed CAS only block transfer operation available in many DRAMs is rendered useless since contiguous column addresses in a DRAM chip are no longer contiguous in 68K's address space. I am not familiar with the graphic hardware of the ST, but the block transfer modes of the DRAM chips are well suited for high speed sequential access of blocks of memory that is typical to bitmap graphic systems.
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!mnetor!seismo!ll-xn!cit-vax!cit-vlsi!wen-king From: wen-king@cit-vlsi.Caltech.Edu (Wen-King Su) Newsgroups: net.micro.atari16,net.micro.amiga,net.micro.68k Subject: Re: 68000 Memory Managment Message-ID: <937@cit-vax.Caltech.Edu> Date: Fri, 29-Aug-86 19:45:02 EDT Article-I.D.: cit-vax.937 Posted: Fri Aug 29 19:45:02 1986 Date-Received: Fri, 29-Aug-86 23:25:04 EDT References: <508@elmgate.UUCP> <64@mit-prep.ARPA> <510@elmgate.UUCP> <417@atari.UUcp> <271@dmsd.UUCP> Sender: news@cit-vax.Caltech.Edu Reply-To: wen-king@cit-vlsi.UUCP (Wen-King Su) Organization: /usr/lib/news/organization Lines: 12 Keywords: 68000 atari amiga 68k mmu