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=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED.fn3LatRFkm9/xzEj7F2/NQ.user.gioia.aioe.org!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: Ada in command / control systems Date: Mon, 25 Feb 2019 16:54:05 +0100 Organization: Aioe.org NNTP Server Message-ID: References: <2199b15b-d704-403f-a6c4-00fab29792d5@googlegroups.com> NNTP-Posting-Host: fn3LatRFkm9/xzEj7F2/NQ.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 Content-Language: en-US X-Notice: Filtered by postfilter v. 0.9.2 Xref: reader01.eternal-september.org comp.lang.ada:55659 Date: 2019-02-25T16:54:05+01:00 List-Id: On 2019-02-25 10:44, Jesper Quorning wrote: > On Monday, February 25, 2019 at 9:24:33 AM UTC+1, Dmitry A. Kazakov wrote: > >> Because the PLC marked is dominated by vendors pushing their vendor-lock >> solutions, e.g. Siemens. > > Is this so different from Ada suppliers? Compiler vendors do not sell hardware. > There are also vendors like Beckhoff (lightweight PLCs) using open standards. There are plenty of software SPS. >> Another reason is the customers lacking elementary programming and >> software design skills. They are usually technicians and electrical or >> mechanical engineers. > > Therefore, Ada is such an advantage. I myself am not a very good programmer, so Ada would help me not be called at 3 am with a production line that does not work somewhere in a remote timezone. Yes, but non-programmers have prejudices and very peculiar ideas about perceived complexity. They consider Ada complex when in fact it is far simpler than tools they consider simple. > In SPS systems, we do not like dynamic memory allocation, so maybe SPARK without a tasking would be sufficient for many applications. The languages ​​used already do what they can to limit the programmer to not make too many mistakes. Formal verification can (and must) be used even if dynamic memory allocation is used. > Technicians and engineers are people too. They try to do what they can with the training af tools they have. Yes and this shapes the landscape of these tools. >> In about 5-10 years so-called industrial solutions will be swept away by >> cheap hardware and hobby software coming from the home automation toy >> projects. These will be far worse than awful SPS, who could think that >> worse were possible? But the force of mass market is overwhelming. SPS >> et al will suffer the same fate as workstations did. > > SPS was also considered dead 20 years ago. SPS is dead, there is no hardware SPS anymore. Software SPS is next. It is to expect some incredibly ugly free tools to appear, some influenced by software SPS, in the sense that they will inherit the worst features of. > However lots of new systems are put into operation every single day. The SPS market is very conservative. When a customer signs an acceptance test he expects the program to be working flawlessly for 15+ years (in principle). That does not matter. When the next generation of engineers come they will use tools they know best. This is how PC eradicated everything else. There will be no more SPS market at all. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de