Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!nrl-cmf!ames!ubvax!versatc!mips!prls!philabs!micomvax!vo From: vo@micomvax.UUCP (Vladimir Orlt) Newsgroups: comp.sys.ibm.pc Subject: Re: Interfacing to the PC bus Message-ID: <1396@micomvax.UUCP> Date: 29 Nov 88 18:31:17 GMT References: <1717@questar.QUESTAR.MN.ORG> <4617@bsu-cs.UUCP> <90@usl-pc.usl.edu> <17932@shemp.CS.UCLA.EDU> <275@greens.UUCP> Reply-To: vo@micomvax.UUCP (Vladimir Orlt) Organization: Philips Electronics Ltd. (TDS - Montreal) St. Laurent QC, Canada Lines: 13 In article <275@greens.UUCP> matthew@sunpix.UUCP ( Sun NCAA) writes: >In article <17932@shemp.CS.UCLA.EDU>, jsin@maui.cs.ucla.edu (Jonghoon Sin) writes: >> 2. I'm finding that the IOW' line is asserted about >> every 15us. Is this normal? What's the PC doing? It's probably the MEMR' line you were looking at. The PC is doing a memory refresh cycle every 15us or so. If you did see the 'IOW line strobing regularly, it could have been a clock-type interrupt being serviced; the IOW' activity could be due to the CPU accessing the PIC. Vlad the Re-mailer ...!philabs!micomvax