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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,d4bb9272b7314785 X-Google-Attributes: gid103376,public From: cgreen@yosemite.atc.com (Christopher Green) Subject: Re: ObjectAda - no clock drift! Date: 1998/06/17 Message-ID: <6m75m3$e4q@newshub.atmnet.net>#1/1 X-Deja-AN: 363371994 References: <6m6f0t$1ue$1@nnrp1.dejanews.com> Organization: Advanced Technology Center, Laguna Hills, CA Newsgroups: comp.lang.ada Date: 1998-06-17T00:00:00+00:00 List-Id: In article <6m6f0t$1ue$1@nnrp1.dejanews.com>, wrote: >Apparently, Aonix has made atomic clocks obsolete with the simple use of a >Wintel PC. > >The Ada rm in D.8 paragraph 41-43 requires vendors to give "an upper bound on >the drift rate of Clock with respect to real time." I was curious what my >Aonix ObjectAda compiler said, so I looked it up. > >The documentation Requirements section of the ObjectAda 7.1 NT docs (p 2-9) >has the following statement: There is no software clock drift. > >What is meant by this? Surely not what I think it's saying! > >T.E.D. I *think* what this means is that there is nothing in ObjectAda to make the clock drift on "Wintel" hosts any worse than it already is. If clock drift with respect to real time is important to you, you should not be relying on the unaided operating system clock of a "Wintel" host, or any product that derives its clock from such a clock. NTP has been ported to Windows NT. I do not know how effective it is at disciplining the clock on NT; it is generally effective on Unix hosts. Visit http://www.eecis.udel.edu/~ntp for details. -- Chris Green Email cgreen@atc.com Advanced Technology Center Phone (949) 583-9119 22982 Mill Creek Drive ext. 220 Laguna Hills, CA 92653 Fax (949) 583-9213