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Article #13491Re: Question: on-chip or off-chip MMU?
From: Tim Smith
Date: Thu, 23 Apr 1987 21:22
Date: Thu, 23 Apr 1987 21:22
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In article <5635@shemp.UCLA.EDU> fan@CS.UCLA.EDU (Roy Fan) writes: > Question 1 : are there any other factors that might affect the >design of the MMU being on-chip or off-chip? I read a claim somewhere that said that it is better to use the on-chip space for floating point, and make the MMU external, rather than have an on-chip MMU and an off-chip floating point unit. The argument was that you have to go off chip anyway to access memory, so it should be possible to make an external MMU as efficient as an internal one, whereas external floating point will be much slower than internal floating point. I have no idea if this is right or not. I prefer an internal MMU because then the system designer can't leave it out! I can deal with missing floating point in software. I can't deal with a missing MMU in software. -- Tim Smith "Hojotoho! Hojotoho! uucp: sdcrdcf!ism780c!tim Heiaha! Heiaha! Delph or GEnie: Mnementh Hojotoho! Heiaha!" Compuserve: 72257,3706
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Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: arc1-ca.pugleaf.net!utzoo!mnetor!seismo!columbia!rutgers!ucla-cs!sdcrdcf!ism780c!tim From: tim@ism780c.UUCP (Tim Smith) Newsgroups: comp.arch,comp.sys.nsc.32k,comp.sys.intel,comp.sys.m68k Subject: Re: Question: on-chip or off-chip MMU? Message-ID: <6047@ism780c.UUCP> Date: Thu, 23-Apr-87 16:22:06 EST Article-I.D.: ism780c.6047 Posted: Thu Apr 23 16:22:06 1987 Date-Received: Sat, 25-Apr-87 14:47:58 EST References: <5635@shemp.UCLA.EDU> Reply-To: tim@ism780c.UUCP (Tim Smith) Organization: Interactive Systems Corp., Santa Monica CA Lines: 23