From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,f8311a3a7edd715 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2000-12-20 04:50:23 PST Path: supernews.google.com!sn-xit-02!supernews.com!nntp-relay.ihug.net!ihug.co.nz!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!xfer13.netnews.com!netnews.com!newsfeed2.earthlink.net!newsfeed.earthlink.net!news.mindspring.net!not-for-mail From: Marin David Condic Newsgroups: comp.lang.ada Subject: Re: Using "delay until" in real-time Date: Wed, 20 Dec 2000 07:50:07 -0500 Organization: Quadrus Corporation Message-ID: <3A40AAFF.2A61C3FE@acm.org> References: <915jl7$jt5$1@nnrp1.deja.com> <3A3F133E.4C13077C@esg-gmbh.de> <91p98c$49d$1@nnrp1.deja.com> NNTP-Posting-Host: d1.56.ba.35 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Server-Date: 20 Dec 2000 12:50:13 GMT X-Mailer: Mozilla 4.75 [en] (Windows NT 5.0; U) X-Accept-Language: en Xref: supernews.google.com comp.lang.ada:3283 Date: 2000-12-20T12:50:13+00:00 List-Id: Its not uncommon to have that sort of limitation, but depending on the system, you can usually reason your way around it. The box gets turned on and run for N hours at most, so we'll never overflow the counter." I had a similar problem once with a control that used EEPROM and there was a major concern about limiting the number of times it would be rewritten. The estimate was that you had about 10,000 writes before the EEPROM would potentially burn out. We were concerned with minimizing the writes to it until I started investigating the probable number of updates. The best guess was that a given control might need the EEPROM reloaded not more than 5..10 times in its production life. In the lab, it might experience 50..100 updates. That left plenty of margin, so we stopped worrying about it. Of course we had to make sure we didn't accidentally get into some sort of loop that might repetitively write a single address - it happened once on another project so people got nervous about it. You always need to look at the real world and sometimes say "Good Enough is Good Enough!" MDC Ted Dennison wrote: > Something pretty much like that has been suggested. My problem with it > is that "n" is a counter that has to be monotonically increasing. That > means that it will eventually hit an archetectural limit. Of course on > my 32-bit machine at 240Hz that limit won't happen until the machine has > been running for about 1/3 of a year, but the limit is there. -- ====================================================================== Marin David Condic - Quadrus Corporation - http://www.quadruscorp.com/ Send Replies To: m c o n d i c @ q u a d r u s c o r p . c o m Visit my web site at: http://www.mcondic.com/ "Giving money and power to Government is like giving whiskey and car keys to teenage boys." -- P. J. O'Rourke ======================================================================