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-Thread: a07f3367d7,3025dd6d917b499c X-Google-Attributes: gida07f3367d7,public,usenet X-Google-NewGroupId: yes X-Google-Language: ENGLISH,ASCII-7-bit Received: by 10.180.73.173 with SMTP id m13mr3122681wiv.4.1350352655312; Mon, 15 Oct 2012 18:57:35 -0700 (PDT) MIME-Version: 1.0 Path: q11ni134324884wiw.1!nntp.google.com!feeder2.cambriumusenet.nl!feeder1.cambriumusenet.nl!feeder3.cambriumusenet.nl!feed.tweaknews.nl!216.196.110.144.MISMATCH!border3.nntp.ams.giganews.com!border1.nntp.ams.giganews.com!border4.nntp.ams.giganews.com!border2.nntp.ams.giganews.com!nntp.giganews.com!news.panservice.it!feeder.erje.net!news.mixmin.net!eternal-september.org!feeder.eternal-september.org!mx04.eternal-september.org!.POSTED!not-for-mail From: Simon Clubley Newsgroups: comp.lang.ada Subject: Re: Ada, the best language with the not-so-best tool chain Date: Tue, 9 Oct 2012 23:23:11 +0000 (UTC) Organization: A noiseless patient Spider Message-ID: References: <38af7fb8-b0a4-4a31-87aa-b7b698cc89c3@googlegroups.com> <3ca0ffd0-1764-484b-8fab-17c0d2dd9463@googlegroups.com> <1f645050-cf4c-40bf-a797-9687b69e4a54@googlegroups.com> <18ats2960nsvm$.kfufsnul13aq$.dlg@40tude.net> <5072c9ae$0$6562$9b4e6d93@newsspool4.arcor-online.net> <4keoa6epdxt7.1nnwxy7v7ar90.dlg@40tude.net> <5072dc68$0$6554$9b4e6d93@newsspool4.arcor-online.net> <1f7cmfp1l65w1.1deog8cfxbs0u$.dlg@40tude.net> <5072e37a$0$6556$9b4e6d93@newsspool4.arcor-online.net> <1kg5574txbj9s.tjfsf4bdpyge$.dlg@40tude.net> Injection-Date: Tue, 9 Oct 2012 23:23:11 +0000 (UTC) Injection-Info: mx04.eternal-september.org; posting-host="e298f3c034f630fa7d024371528fc2e1"; logging-data="4234"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19nYdYS2yvTtizqMuSPhhoXOUv2TsjEc84=" User-Agent: slrn/0.9.8.1 (VMS/Multinet) Cancel-Lock: sha1:qQw5nCkc9gDWWJyfOPXVkrUe83o= Date: 2012-10-09T23:23:11+00:00 List-Id: On 2012-10-09, Dmitry A. Kazakov wrote: > On Tue, 9 Oct 2012 08:53:01 -0700 (PDT), kalvin.news@gmail.com wrote: > >> tiistai, 9. lokakuuta 2012 16.17.55 UTC+3 Dmitry A. Kazakov kirjoitti: >>> The problem is that an integrated I/O usually has only on ADC. So to >>> measure two inputs you need twice so much time plus the time needed to >>> switch the ADC to another line. This is how you quickly come over 10ms. Not >>> to forget inability to measure inputs and change the outputs synchronously. >> >> Quite a few microcontrollers have two or more A/D inputs and D/A outputs >> that can sample simultaneously and update outputs synchronously. > > That is why GPIO is useless in my eyes. > You are confusing GPIO for analogue operations with GPIO for digital (logic 0/logic 1) operations. I have found the latter to be far more common, at least for the things I do. >> If one needs more simultaneous sampling A/D inputs or D/A outputs, then >> one may have to use an external IC for this. > > http://www.beckhoff.com/english/ethercat/el3054.htm > http://www.beckhoff.com/english/fieldbus_box/ep3174.htm > etc > Let's make this discussion more tangible by using a specific example. The scenario: a hobbyist/academic researcher/whoever is building a small computer controlled model aircraft, in the order of up to about a metre in length for the fuselage. This size means that a PC-104 is way too bulky and heavy for the onboard computer, but the latest ARM boards, with their integrated I/O, are a very good fit. Normal R/C electric engine controllers and servos are used in this model aircraft and need to be interfaced to the onboard computer. Question 1: if you could not use GPIO lines to control commodity R/C components, how would you have the onboard computer control the engine and flight control surfaces ? To make this on topic for this newsgroup, this seems to be a common hobbyist or researcher project in a number of circles, and is _exactly_ the type of project for which Ada would be very well suited indeed. It's also the type of project which would raise Ada's profile big time if hobbyist/researcher type people started using Ada on a regular basis on them. It's also the type of project generally done by people on restricted budgets. Question 2: how would you put the idea of using Ada for this project into someone's head and what changes to the Ada ecosystem would be needed to make it viable for people with different ranges of embedded experience to actually use Ada in this case ? Simon. -- Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP Microsoft: Bringing you 1980s technology to a 21st century world