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