Path: csiph.com!eternal-september.org!feeder.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail From: Bobbie Sellers Newsgroups: comp.os.linux.misc Subject: Re: Hot-swap-ability of PS/2 devices (Was: Cursor while booting) Date: Thu, 17 Mar 2016 13:03:15 -0700 Organization: A noiseless patient Spider Lines: 81 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Injection-Date: Thu, 17 Mar 2016 20:00:08 -0000 (UTC) Injection-Info: mx02.eternal-september.org; posting-host="ae1ba725f35f9234a391060b2ff8bf3f"; logging-data="4152"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+t5tLXDKmRB13YaR5IKQkg" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.7.0 In-Reply-To: Cancel-Lock: sha1:C1SObrfjOMyGEosGEHhssHYjPGs= Xref: csiph.com comp.os.linux.misc:17051 On 03/17/2016 12:14 PM, William Unruh wrote: > On 2016-03-17, Bobbie Sellers wrote: >> On 03/17/2016 09:42 AM, William Unruh wrote: >>> On 2016-03-17, Keith Keller wrote: >>>> On 2016-03-17, Kenny McCormack wrote: >>>>> In article , >>>>> Keith Keller wrote: >>>>> ... >>>>>> I know this is true in theory, but I have plugged/unplugged PS/2 devices >>>>>> with the power on probably hundreds of times over the past 20 years, and >>>>>> have had one device and one port fry in that time (in unrelated separate >>>>>> incidents). If you can power down, great. If not, the risk is low, >>>>>> just be very very sure that you can make alternate arrangements in case >>>>>> you do fry something. >>>> >>>>> So, in conclusion, it seems pretty clear that the previous poster's advice >>>>> was much more in the category of "This is what we must tell beginners" than >>>>> in the "This is what is actually true" category. >>>> >>>> It is really true; as I said, the incidence of failures I have seen is >>>> definitely nonzero, and the connectors were definitely not made to be >>>> hot-plugged. >>>> >>> >>> Well, there are two questions, one is whether plugging something in/out >>> destroys something, or whether the hardware does not report anything to >>> the system that something has been plugged in/out. The former is a case >>> of completely incompetent engineering if it is the case. Anything that >>> is plugged in could be disconnected by accident or even >>> connected/disconnected repeatedly by a loose contact, and if it is not >>> engineered to take that, it is incompetent engineering. I am of course >>> not saying that incompetent engineering does not occur, but it is surely >>> not the norm. >>> >>> >> >> In the early stages of home computing you still had to observe >> a lot of rules to keep from short-circuiting your connectors. I wiped >> out my 64 kilobytes of memory on the Commodore 64 by not observing >> proper protocols as to connecting cables only when cold. >> >> The engineers who designed and built them wrote the cautions >> into the manuals and expected(foolishly) that people who valued their >> hardware would read the manuals and so forth. By the time I got to >> my Commodore Amigas I had learned that lesson well. I was >> happy when USB came along and it was no longer the necessity it >> formerly was. >> >> Incompetent engineers or incompetent users is beside the >> point. The engineering is improving but the users are much the >> same as in the 1980s when I plugged in my C=64. Of course with >> all the net connectivity that "just happens" for the users we >> don't have some problems that were "learning opportunities", > > Users are always incompetent. They have not been trained, have not spent > 4 years at university studying how to use their equipment. Engineers > have, and should have been trained as to how to design equipment > properly. It is like saying that when a doctor botches up and operation, > one should expect it, because the use ( the person under the knife) > could be incompetent at operations as well. > > Imagine if cars were that way. The manual says that if you happen to > press on the accelerator and the brake at the same time even briefly, > the3 engine explodes sending shrapnel all around. Do you thing that > manual mention would be considered sufficient to absolve the engineer of > fault and blame? And yet we accept behaviour like that from computer > people. The whole absolution of blame in the computer area-- harware of > software-- is astonishing. They make lots of money so they should not be > blamed for anything. > >> >> bliss >> >> Well they build the toys we are foolish enough to buy so it is not money but creativity that buys them a pass. Users may be incompetent but they can learn. Engineers have to produce what the company thinks will sell. bliss