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John U

 Discussion on answer by Seamus: Curre…

Imported from a comment discussion on raspberrypi.stackexchang...
John U
May 8, 2024 18:58
That's a shame, but certainly wouldn't be the first case of that sort of thing happening.
John U
May 8, 2024 18:58
wiringpi.com is a single page that reads: "This is wiringpi.com. As of the end of 2023, you'll not find anything here anymore. It's gone." that does not fill me with reassurance that I want to base my project on it, however the repo you linked is certainly more positive... just a shame people can't join things up so Gordon's website points to the new team or something.
 

 Discussion on question by John U: Tou…

Imported from a comment discussion on electronics.stackexchang...
John U
Dec 15, 2022 16:40
@MicroservicesOnDDD I really doubt this is about the impedance of the PCB traces, the main rail is 100mils wide copper and there's not only a ground plane but ground pours on the other 3 layers with plenty of via stitching.
John U
Dec 15, 2022 15:45
@winny I think it's called aliasing, where a HF signal looks like a much slower one. But I had checked it on a faster time-base before my original post, I just thought the longer view gave a better impression of the overall signal (bursts of noise) rather than a specific capture of the 50Khz waveform.
John U
Dec 15, 2022 15:45
@TimWilliams C94 was 100nF MLCC, then I added a 10uF MLCC on top of it (stacked 0603's). Adding a 47uF electrolytic across the pads of C94 had no appreciable effect. I can't say for sure this is a problem but the touchscreens are sometimes causing problems (I2C lockups) which is what led me here, and the spikes feel unwelcome at the very least. GT911 specifies <=50mVpp supply ripple so we're borderline.
John U
Dec 15, 2022 15:45
@TimWilliams the scope shows ~15mV common-mode noise when doing that, which is about the background level for the Rigol it would seem.
John U
Dec 15, 2022 15:45
@winny just for you I made a pigtail and re-measured it right across the ends of C94 and it made no difference at all to the trace.
John U
Dec 15, 2022 15:45
@tobalt I added 2x 100R in parallel but no difference - the AP7366 is stable with zero load and it's a linear LDO which doesn't have different modes of operation.
John U
Dec 15, 2022 15:45
@tobalt I added a 47uF electrolytic on the 3v3 rail and it made almost no difference.
John U
Dec 15, 2022 15:45
@winny it's the standard ground clip so maybe 80-100mm long, I'm sure you can visualise a standard scope probe without me taking photographs of it for you?
John U
Dec 15, 2022 15:45
I have no idea of the specs of the FPC, the screen is a bought-in module and the manufacturer would not know that spec either. R157 + R158 are the I2C pullups, 4k7.
 

 Discussion on question by user268759:…

Imported from a comment discussion on electronics.stackexchang...
John U
Nov 19, 2020 16:07
TS100 and clones are pretty cheap these days and seem popular: hackaday.com/2017/07/24/review-ts100-soldering-iron
 

 Discussion on answer by Lambie: Why c…

Imported from a comment discussion on ell.stackexchange.com/qu...
John U
Apr 3, 2019 14:26
Just to add - in slang / idioms you could say "I am having a dog of a day", and some people may shorten it to "I'm having a dog", but that is a very different thing.
 

 Discussion on answer by jlliagre: Why…

Imported from a comment discussion on unix.stackexchange.com/q...
John U
Dec 22, 2017 13:29
@TED - I'm fairly sure I've read that the Amiga OS was based on or at the very least inspired by *nix, I believe they developed it on *nix machines (as well as the infamous surfboard joystick, natch).
 

 Discussion on question by user1833028…

Imported from a comment discussion on workplace.stackexchange....
John U
May 6, 2017 10:19
Also, I'm with the comments above that it sounds like a site-related electrical supply issue - floating ground, stuff connected to different phases, that kinda thing. Bounce over to the electrical engineering stack and ask.
John U
May 6, 2017 10:19
1st and foremost, to quote a friend of mine: Wallpaper your entire ass. Send an e-mail or note or something traceable / recorded to your boss and keep a copy to prove that you at least did the decent thing. If you meet hostility / resistance, fine, others here will steer you through that. But you need to tick the box marked "bare minimum number of sh*ts given" to cover your backside when the lawsuit starts. The e-mail doesn't need to be controversial / provocative / career limiting, it's purely about a paper trail. Good luck!
 

 Discussion on question by Selyuu: My …

Imported from a comment discussion on money.stackexchange.com/...
John U
Mar 6, 2017 19:06
If he shops around / talks to an IFA he might find a better deal / more money than the banks are willing to lend without dragging you into this. If he can't, it's because he's not as good a prospect as he believes he is. YOU need to stay the hell away from it.
 

 Discussion on question by John U: Man…

Imported from a comment discussion on workplace.stackexchange....
John U
Jun 10, 2016 16:45
I'd also add that the workplace side of the question is more easily handled in a professional way. When the person is a friend or family member who you don't work with and aren't the boss of, it's hard to try and help them out of this behaviour potentially against the prevailing expectation their employer/colleagues put on them.
John U
Jun 10, 2016 16:42
@kent - I'm in the UK. Certainly no-one minds employees working extra time over here, and indeed many companies (especially American ones with UK presence) have imported the US culture of going way beyond the contracted hours as a matter of course. That's fine for a while or for young keen climbers of the greased pole, but when someone is just running themselves into the ground for little gain, reward, praise, or personal progression seemingly against their will it's just a bad situation.
John U
Jun 10, 2016 10:59
Well Richard, I don't know how you managed it but I guess you're probably owed about 50 upvotes for that edit.
John U
Jun 10, 2016 10:59
Someone's done it for me, and phrased it better than I could - if I could upvote edits I would.
John U
Jun 10, 2016 10:59
I'm not arguing that, I'm just a bit taken aback that such close scrutiny (and weight) is put on the exact wording I used rather than the overall spirit of trying to help friends/colleagues. I didn't quite expect downvotes for trying to help people, but maybe that's a life lesson!
John U
Jun 10, 2016 10:59
The phrase "workplace martyr" is a relatively well-known description of the behaviour as far as I was aware, maybe only in the UK. The "tone it down" phrase was simply because I was unsure what the correct term would be - chill out, tone it down, back off, refocus, get with the plan... I'd never make a therapist that's for sure. I thought the general spirit of the question (concern, desire to help) was obvious but it would seem I didn't quite hit that apex either.
John U
Jun 10, 2016 10:59
@JaneS - undoubtedly talking to them is the way forward, but the question is how to communicate the idea that their behaviour is not helpful to them or others? Their view is that they must behave this way or things will fail, so how can one persuade them that, even if it does mean some things will fail, that is a preferable/acceptable outcome?
John U
Jun 10, 2016 10:59
@Lilienthal - I'm not bitter, I'm concerned, as I have said at least twice now, it's adversely affecting their health & wellbeing. I'm not angry at these people, I'm worried that they are burning themselves out and not being as helpful as they think they're being. If I was a purely cynical person I'd say let them take on as much as they like as it saves hiring extra people, paying overtime, etc.
John U
Jun 10, 2016 10:59
What if your own work is to manage those people, and it would be beneficial all round if you could manage to reduce this behaviour?
John U
Jun 10, 2016 10:59
Really? Wanting to help people who cause themselves excess stress, cause their own work (and home life) to suffer, and mask underlying problems in either management or process is an unanswerable question of me interfering in others' lives?
 

 Discussion on question by Lyrl: Singl…

Imported from a comment discussion on workplace.stackexchange....
John U
Apr 26, 2016 01:02
Is it possible to shuffle roles around so he can remain employed but in a more flexible role? I'd hope in a company with ~20 employees there might be enough wiggle room that some compromise can be found. Also worth saying: Try and engage other employees too, nothing worse than that one guy getting special treatment... you might find some other employee (or new hire) would actually be glad to share a role that's a bit more flexible, and both of them cover the other as needed.
 

 Discussion on question by Nate Kerkho…

Imported from a comment discussion on security.stackexchange.c...
John U
Feb 27, 2016 15:08
tl;dr: Same reason it's easier to accidentally cut yourself with a scalpel than safety scissors.
 

 Discussion on question by Billy ONeal…

Imported from a comment discussion on security.stackexchange.c...
John U
Oct 27, 2015 07:58
Having read this with interest, one thought occurred to me about a different sort of attack not mentioned so far: key loggers. You could very easily guess that "Tr0ub4dor&3" cropping up in a log is a password, whereas normal words separated by spaces or regular punctuation would not stand out so far. Just a thought.
 

 Discussion on answer by Iszi: How to …

Imported from a comment discussion on security.stackexchange.c...
John U
Jun 19, 2015 10:22
The ability to keep the line open is a useful (sometimes vital) function for example emergency services, and is a function of the telephone exchange equipment that the end user can't control no matter what (POTS) phone you have. I'm surprised scammers etc. can access it but it's likely a function of the ISDN signalling they can can control/inject from their PBX (these days, software). An easy test is to dial something the scammers can't easily emulate - speaking clock, telco's line test number, etc. Disclaimer: My experience is UK network.
 

 Discussion on answer by haylem: Shoul…

Imported from a comment discussion on workplace.stackexchange....
John U
Jun 17, 2015 01:05
Not directly related to this but a side-tip from an old boss, the company had a habit of spewing directives and demands from above which another manager was always fire-fighting to comply with: When JFDI arrives in your inbox, leave it there. When someone gets in touch to ask why you haven't done it yet, then apologise for missing it & do it. 99% of the time, whatever it was they wanted has been changed / rendered obsolete by mismanagement and you will never get chased for it. (JFDI == "Just f**ing Do It", the colloquial term for these asinine directives from the pointy-haired boss above)
 

 The DMZ

A serious place where infosec is discussed PS we don't do hard...
3
John U
Jan 8, 2013 14:11
@LucasKauffman - well aware that homebrew is generally a bad idea
John U
Jan 8, 2013 13:57
Not in the Department of Redundancy Department?
John U
Jan 8, 2013 13:27
In relation to our system, there will inevitably be a certain degree of responsibility on the end user to secure their network, or the part that their security system uses (for obvious reasons) so hopefully we don't have to defend against the entire internet. Having said that, I realise that doesn't really change or reduce the job at hand.
John U
Jan 8, 2013 13:21
@RoryAlsop Ah, I have two different Daves here
John U
Jan 8, 2013 13:15
Perhaps a starting point is how we work out the resilience of what we've got - if the base OS is secure, if the server stands up to abuse, etc., any advice on the basic toolkit for trying to break it so we can fix it?
John U
Jan 8, 2013 13:12
@LucasKauffman - any particular Dave?
John U
Jan 8, 2013 13:11
@AviD - we can modify the source, run a different server (lighttpd for example), we could build PHP or .cgi's etc. but it's got to be very lightweight compared to what you could throw around on a full-fat system.
John U
Jan 8, 2013 13:09
Securing the web interface will be a bundle of joy, the example s/w that comes with the dev kit uses a really nasty ActiveX object which pretends to be secure but just does HTTP auth, it's naaasty
John U
Jan 8, 2013 13:08
Yeah, I know... I just mean anything serious running server-side, as it doesn't have the computrons to spare for the usual stuff one might do to secure a server
John U
Jan 8, 2013 13:06
I've read enough to know rolling your own anything is To be Avoided
John U
Jan 8, 2013 13:06
It's running Linux 2.6.37, existing web-server is Boa 0.94, it will be streaming video over RTSP & have a web interface for config - but currently nothing clever like PHP,SQL as it's relatively low-powered (think Raspberry Pi kinda specs)
John U
Jan 8, 2013 13:01
On a slightly different tack, what would be the most common issues/vulns with a small network-connected device? (As opposed to server/website/database)
John U
Jan 8, 2013 12:58
I have the Addison-wesley books on TCP/IP (amazon.co.uk/…)
John U
Jan 8, 2013 12:55
...spotted that one in the popular section of Amazon
John U
Jan 8, 2013 12:55
@lucas Hadn't
John U
Jan 8, 2013 12:52
I'm starting a project using embedded linux in an ip-connected security camera (we are developing it based on a reference dev system), coming from an embedded-C background I am an ip/linux n00b and wondering where to start reading... any guidance appreciated (yes a very broad question I know!)
John U
Jan 8, 2013 11:44
Having barged in and insulted the Scots, can I don my best n00b hat and ask some security type questions of you guys?
John U
Jan 8, 2013 11:30
Pffft, the 6 days a year it's not raining in scotland it's 'cos it's snowing, surely?