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=-0.3 required=5.0 tests=BAYES_00, REPLYTO_WITHOUT_TO_CC autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,779e26feb708bd00 X-Google-Attributes: gid103376,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news1.google.com!news4.google.com!news.glorb.com!npeer.de.kpn-eurorings.net!news.uni-stuttgart.de!news.belwue.de!newsfeed.arcor.de!news.arcor.de!not-for-mail From: "Dmitry A. Kazakov" Subject: Re: embedded programming for unreliable hardware Newsgroups: comp.lang.ada User-Agent: 40tude_Dialog/2.0.14.1 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Reply-To: mailbox@dmitry-kazakov.de Organization: cbb software GmbH References: Date: Wed, 15 Feb 2006 10:17:16 +0100 Message-ID: <1ndy2tjefyddo.1a02jjir70zm4.dlg@40tude.net> NNTP-Posting-Date: 15 Feb 2006 10:17:17 MET NNTP-Posting-Host: 64a28ee5.newsread4.arcor-online.net X-Trace: DXC=b:NU7dQn89Jo47S\@TX3oE:ejgIfPPldDjW\KbG]kaMHGAlE^3P3k5Ehag_UJK]3KEmWkfB4cNm_@:\WV9b@@LaAS29W6=M?7UJ X-Complaints-To: usenet-abuse@arcor.de Xref: g2news1.google.com comp.lang.ada:2903 Date: 2006-02-15T10:17:17+01:00 List-Id: On Wed, 15 Feb 2006 05:54:27 GMT, Jeffrey R. Carter wrote: > For actuators, it depends on whether you command to an absolute value or not. If > you command to an absolute value ("turn on") then issuing the command twice > should ensure that it's performed. If you command a relative change ("toggle > power") then you'd need to issue the command, check the result through a sensor, > and reissue if it didn't take. Issuing twice will work 99.75% of the time. Somewhat complementary technique is safe actuators design. Some actuators have a safe-state command, they perform it automatically if no new command comes. For example, a lift truck holds on the load by default. If you want to lift it up, you have to permanently repeat "up", "up", "up"... Should one command not arrive, no problem. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de