*BSD News Article 19564


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Xref: sserve comp.periphs:4135 comp.realtime:3568 comp.os.386bsd.development:1077
Newsgroups: comp.periphs,comp.realtime,comp.os.386bsd.development
Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!elroy.jpl.nasa.gov!swrinde!cs.utexas.edu!uunet!pipex!ibmpcug!ibmpcug!jshark!joe
From: joe@jshark.inet-uk.co.uk (Joe Sharkey)
Subject: Re: Why fix the RTC (Real Time Control) for 386bsd
Organization: Individual Network (UK)
Date: Tue, 17 Aug 1993 00:24:47 GMT
Message-ID: <CBvntC.Iys@jshark.inet-uk.co.uk>
Keywords: RTC report 
References: <jmonroyCBuLr1.7L3@netcom.com>
Lines: 63


Oh, no, J.Monroy, you're doing "it" all over again....

Why:-(  Will we learn anything? Will we get a better OS?  A nice happy feeling?


In article <jmonroyCBuLr1.7L3@netcom.com> jmonroy@netcom.com (Jesus Monroy Jr) writes:
>                The text that follows is self-explainitory,
>        except that this is only the first 40 lines of the
>        report.

Usually, "RTC" == "Real Time Clock". Do you mean this too?

>=====================================================================
>Reasons to fix the RTC.

Is it broken? How?

Unix has used several "Real-Time Clocks" since the PDP days - what was
wrong?  Why did no-one notice?

If you have access to BSTJ, you may want to look at derivatives such as
MERT before making a definitive answer.

>                At the request of Bill Jolitz and other, I have
>        written this report.  I should note that this is NOT a request
>        for a Real-Time OS (Operating System).  Also, I was a bit
>        unaware of the lack of work done in this area, RTC (Real-Time
>        Control). My assumption was that other had this knowledge, as
>        second-hand, just as John Sokol and I.

Geez, Jesus, subtle you aren't!

*I* thought preventing reactors going critical was in the "RTC" area -
well, maybe you're a bit more laid back in California?

Real-Time Operating Systems are different from UNIX:  have you managed
to work out why a QIC-40 driver is *so* difficult to write.

>        sections are broken up by a set of triple dashed lines with
>        the section number in the center of the line.  The first
>        section shows that time is an issue and planning is better
>        than post (or run-time) analysis.  The second section shows
>        that interrupts and the error recovery process are the main
>        contentions for efficient context switching and kernel
>        operations.  So, not having a failure will greatly increase
>        system efficiency (This should be a Given.).  Section Three
>        answer the popular myths about RTC. In section four are
>        comments  from   Mr. David Brown of UCSD  about his
>        experiences with the QIC-40/80 implementation.  Lastly in
>        Section Five are my comments and recommendations.

I don't even understand the synopsis of section two :-(

Jesus, are you using the same terminology as the rest of the world?

>Jesus Monroy Jr

joe.
-- 
Joe Sharkey      joe@jshark.inet-uk.co.uk      ...!uunet!ibmpcug!jshark!joe
150 Hatfield Rd, St Albans, Herts AL1 4JA, UK        Got a real domain name
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