Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!uwmcsd1!leah!itsgw!steinmetz!uunet!iscuva!jimc From: jimc@iscuva.ISCS.COM (Jim Cathey) Newsgroups: comp.sys.mac Subject: Re: Why do Macs have ROMs? Keywords: Macs, ROMs Message-ID: <1710@iscuva.ISCS.COM> Date: 5 Jul 88 19:52:07 GMT References: <453@etive.ed.ac.uk> <13155@apple.Apple.COM> Organization: ISC Systems Corporation, Spokane, WA Lines: 17 In article <13155@apple.Apple.COM> lsr@apple.apple.com.UUCP (Larry Rosenstein) writes: >Another historical reason for the ROM is that on all the Macs before the Mac >SE and Mac II, the video circuitry was competing with the CPU for the RAM. >Therefore, code running out of ROM ran faster than out of RAM. It is my understanding that the CPU and Video still compete for RAM access on an SE, but that they do it less often (because the Video grabs 32 bits at a time rather than 16). A minor nit in any case. +----------------+ ! II CCCCCC ! Jim Cathey ! II SSSSCC ! ISC Systems Corp. ! II CC ! TAF-C8; Spokane, WA 99220 ! IISSSS CC ! UUCP: uunet!iscuva!jimc ! II CCCCCC ! (509) 927-5757 +----------------+ "Yours for excruciating correctness..."