Silicon Valley Redneck

"covfefe": typo, or secret code?

How about a typo of a secret code?

The actual secret code word is "cowfife" - which could be an obscure musical instrument once popular with 16th century Yorkshire peasants, but which nowadays (outside of performances at SCA events) is the authorization code for a nuclear attack on Lower Molvania.

Trump tweeted the "typo" to put the Lower Molvanians on notice that he's quite willing to say the actual word, should they fail to settle their tab at the Trump Casino.

Chronotype gap

Seen at Twitchy, some news-writer I don't think I'd heard of before has gotten all bent out of shape about The Orange One's habit of consuming Diet Coke at 1030:

I'm serious. How many of you think it is acceptable to drink diet coke before 11 am

Er.  Excuse me?

Some of us start caffeinating at 0400, or even earlier.

And have to stop before 1100.  Caffeine too late in the day is bad news.

I guess night owls just don't grok this.

Argh.

Brought up the firmware on the second USBTMC gadget.  Ran a test script.  Got an oopsie.

Looked like a buffer overrun, except that I was putting 53 bytes into a 512-byte buffer, so nope.

Then... it looked like a channel list with 32 characters between the parentheses might be the culprit.  This made no sense whatsoever, given that the channel-list parser runs entirely on the fly, without maintaining any buffers of its own.

Moving extra whitespace around, I eventually figure out that the problem was a command line longer than 52 characters.  Um...

That's right about a 64-byte packet minus a 12-byte header.  And the gibberish that came after looked remarkably like the headers of following packets.  A quick capture with the USB Beagle confirmed this.

So, some issue with my implementation of USB_DeviceTmcBulkOut, and the logic for determining when EOM has been processed and we should be looking for a new header.

I'll do some further tracking after dinner.  Tomorrow should bring Real Work, as in for a paying client, so the gadget project will have to return to the back burner.

Update: Derrrrrr.  This was a case I hadn't tested before, because the first gadget doesn't take any lengthy commands (unless one pads a command with extra whitespace, which I hadn't thought to do).

I'd tested multi-packet messages coming back from the gadget; *IDN? exercises that one nicely.  I hadn't tested multi-packet messages going to the gadget.

And, surprise surprise, I'd neglected to update a byte counter, so the first message with a continuation packet (which is to say, message length exceeding 52 bytes) broke the logic.

I keep thinking that before any of this goes to production I should restructure the whole SCPI-parsing subsystem to suck directly from the input stream instead of buffering a command line.  That'll be important when I start building things to which the PC will send waveforms (or other large data blobs).

It's not just technology.

Or... the problem with incentives extends to old-school biotech, too.

We've all seen it in the gadget area: shiny things that meet all the standards, are fully buzzword-compliant, and, somehow, just aren't very good at doing their actual jobs.

Sometimes this is the result of Marketing running amok, and shiny-feature requirements displacing functional requirements.

Sometimes it's the result of government intervention, as with energy- and water-efficient washing machines that don't get the clothes clean and need to be run a second time, using more energy and water in total than the old model would have used.

I'd been vaguely aware, for many years now, that there were significant issues with some dog breeds.  The problem turns out to be much worse than I'd realized - and it's largely the result of the standards-setting organizations setting standards that correlate poorly (in some cases, negatively) with practical considerations such as health, temperament, intelligence, and the ability to function as working dogs.

CDR Salamander rants at some length on the topic, echoed, in regard to the feline species, by Wyldkat.  These via Peter Grant.

Hey, I've got a trio of robust, healthy, playful cats, and I didn't have to spend zillions of dollars each.  Just found 'em in the backyard blueberry patch, being raised by one of the neighborhood ferals.  No papers, no conformance to any identifiable breed standards, but who cares?

And Huckleberry thinks your purebred, certified, best-of-breed purse dog is a squeak toy, so there.

Cross-field analysis sometimes doesn't work well.

A linguist looks at the weirdnesses of English.

It's a good read, but... a few things jumped out at me.  In particular:

Greek is another element: in an alternate universe, we would call photographs ‘lightwriting’. According to a fashion that reached its zenith in the 19th century, scientific things had to be given Greek names. Hence our undecipherable words for chemicals: why can’t we call monosodium glutamate ‘one-salt gluten acid’?

Two things, just in this one snippet.

The photographs/lightwriting thing?  Just a side note, but Russian seems to have done almost exactly the same thing as English, but borrowing differently from dead languages - ending up with words like "stomatology" and "fluorography".

And, "one-salt gluten acid"?  Two important points here.

First, science is international.  Rather than standardizing on German back in the day, the community ended up borrowing from dead languages for naming things.  (I don't know whether the existence of formal bodies for admitting new words to the better-standardized European languages played a role in this.)  Just-using-plain-English-already wasn't a realistic option, given that English wasn't the primary language of science back then.

Second, "one-salt gluten acid" bloody well doesn't mean the same thing as "monosodium glutamate"!  Yes, "salt" is a perfectly good English word, which is casually understood to refer to a specific compound, sodium chloride.  First problem: a sodium chloride molecule and a sodium ion are not the same.  Second problem: to a chemist, "salt" has a much broader meaning.  Third problem: the compound in question is not an acid, but a specific salt thereof.

Another big thing may be unwinding.

The whole clean-diesel thing.  Diesels always used to be dirty, but then the EPA demanded clean diesels, and manufacturers came up with ways of complying.  If they can meet the current standards, previously considered impossible, then all we have to do is tighten up the standards some more, and we'll get even cleaner vehicles!

Oh, there are little problems.  Seems that the manufacturers of the engines used in small farm tractors are having a hard time meeting the current standards at any sane price, leading at least one tractor company to redesign their product around a gasoline engine (which is substantially inferior for the application, but meets the standards - see also "efficient" washing machines, etc.).

And, oh, it turns out that Volkswagen wasn't really meeting the current standards after all.

Now there's this story over at Rodent Rack: there are rumors that Government Motors was also rigging its emissions tests.

Funny thing.  Make compliance too difficult, expensive, or otherwise unprofitable... and people find ways to cheat.  Add more direct supervision of the compliance tests instead of trusting self-reporting, and you'll find inspectors inexplicably living beyond their means.

Obsessing over details...

... that are fictional anyway.  What a fun way to spend one's time!

Having been out of touch with the hard-core fans of Star Trek, Star Wars, War Treks, and Trek Wars since about, oh, freshman year of college, I didn't realize how much effort people had put into filling in the fiddly details of, for example, the Star Wars universe.

This being particularly silly, given that it's all based on creating fictional details that align with fictional physics and with things for which no actual clue is offered in the original source material.

Consider: What Do the Buttons on Darth Vader's Suit Do?

Objectively true answer, in this universe: Nothing.  They're bits of a costume.  They're just as functional as the portable doorbell button on the old Mission: Impossible show.

Alternative answer, as valid as any:

The four rocker switches are for the power windows.  The one on his far left, if held firmly in the "down" position for four seconds, activates the emergency-escape feature, which is why it's red.

Those two buttons, one red, one blue?  The red one dispenses a hallucinogenic drug, allowing Vader to chase wild hares down rabbit holes; the blue one dispenses the antidote, returning him to normality.  Alternatively, the blue one dispenses the hallucinogen, allowing him to believe in the "normal" world of the films; the red one dispenses the antidote, returning him to the full bizarreness of the real world.

The two, mirror-imaged boxes'o'buttons on his utility belt are remote controls: one for the VaderMobile and one for the VaderCopter.

And, as to why he didn't get a more modern suit somewhere along the line: The writers wouldn't allow it.  You can't have an iconic villain go off and get a makeover between movies, returning in some entirely new and not-so-villainous form.  The outdated prosthetics are in Vader's contract!

Added: Being sillier still, I'm now trying to come up with a vision of a Vader/Batman crossover costume.  But not the modern Batman, oh no indeed; he's much too close to Vader already.  Stick some pointy ears on the helmet and change the thing on the chest, and you've just about got it.  No, I'm thinking of the Adam West edition... and a Darth Vader of corresponding unseriousness.

More: The wording above is suboptimal; I meant of course that adding pointy ears to Vader's helmet would get darn close to New Batman.

The costume concept is evolving into: Suppose the role of Darth Vader had been played by Adam West?

And, while we're at it... Vader wears a cape.  So.  Shouldn't one of the controls on his chest box be for flying, like the knob on Commando Cody's chest box?  Or is the fuel for making him fly no longer available, which would also explain why R2D2 lost the power of flight between the prequels and the original trilogy?

All this effort to justify a very silly costume: The story so far: Anakin Skywalker had a twin brother, Bruce, who was adopted at birth by a wealthy off-planet couple.  Their paths never crossed again until that fateful episode in 1967, featuring "Special Guest Villain: Adam West as Darth Vader".  (Yes, the TV technology of the day was up to having two characters played by the same actor on the screen at the same time, with some constraints.)

This implies that Batman himself is a feral Jedi, but why shouldn't he be?

Saturday morning randomness

On the must-have list for post-relocation life: an office/desk configuration that discourages feline encroachment on the desktop murine arena*.

Because it's really hard to use the mouse when there's a cat holding one's hand.  Both Huckleberry and Top Hat do this a lot.

---

I don't shop at normal grocery stores that much these days.  Yesterday, though, there were a couple of items on the shopping list that seemed to call for a trip to Safeway.  As long as I was there, I might as well get some other, could-buy-anywhere stuff, right?

Gah!  The prices!  Have you priced a little 8-ounce can of tomato sauce lately?  Safeway wants north of a whole dollar for any of the name brands.  The store brand is "only" 50¢ a can.

And Kerrygold butter was way more there than at Trader Joe's.

What's more, they didn't have one of the items I specifically sought there: gourmet pepperoni.  No place for it to be, even.  Guess that has to come from Nob Hill, which is more of a detour (but is conveniently located next to the 99 Ranch).

---

Speaking of tomato-sauce pricing: How come a 15-ounce can typically costs more than two, 8-ounce cans?

Relatedly... I was checking the prices and features of yet another PC-board fabrication service a few days ago.  For a given board, it looks like the minimum unit price comes at a 10-piece order.  Order more than 10, and the price per board goes up.  Eh?  Well, it is a quick-turn service, but... does this really make sense?  (I was only doing the price check based on one board spec, so maybe the pricing is based on total area, and going past 70 square inches means they have to schedule extra board runs?)

---

Seems it pays to shop around for moving boxes.

I figure I may as well pack up and store a bunch of stuff that I need to keep, but don't expect to use any time real soon.  In the process, I'll certainly uncover lots of stuff that can go to recycling or whatever.

This calls for a stack of medium-sized moving boxes.  Order from Amazon, maybe?  Nope; looks like that category is kind of pricey.  Also pricey from Home Despot, and from Wally World.

Best deal I find on a quick-ish search is U-Haul.  Which comes out way cheaper than some of those other places.  Guess they figure on customers subsequently renting their trucks to transport the filled boxes (as will likely be the case).

---

The gophers are still active.  I put some more poison in the region of new activity.

Still don't know whence these came.  Maybe some evil developer has been air-dropping gopher seeds to reduce property values.

I wonder if hosing down the low-growing vegetation with sriracha sauce would discourage them.

 

* Murine arena: mousepad.  Nothing to do with eye drops.  I dunno why you'd want to put mice in your eyes anyway.

Discomprehending basic economics

The author of this piece at Frob's, in criticizing another's work, quotes (but doesn't criticize the premise of) this bit:

If a primary national goal is to create jobs in the energy sector, investing in renewable energy is considerably more effective than investing in fossil fuels.

But... but...

"Creating jobs" isn't a proper goal, is it?

Work is fundamentally important to humans, but it has to be productive, or otherwise meaningful, work.  Hire people to spend the rest of their working lives digging holes one day and filling them in the next, all visibly to no purpose, and what good does it to for anyone?

If we want to maximize job creation in the energy sector, we could just build giant hamster-wheel farms, and put people to work running in the wheels to turn generators.  Epically inefficient in terms of power generation, but very effective indeed at creating jobs.

A job exists because there's a specific need for labor to carry out a task that, in some manner, creates wealth.  Putting the existence of the job ahead of its purpose makes no sense, unless it's your brother-in-law's job or something.

Ah, the wonders of mass production!

A while back, I spotted on Amazon something that was just too good to pass up: a 10-pack of red laser modules for, if memory serves, $2.71 including (slow) shipping.  Naturally, I just had to order two.

Well, the postman just delivered a small plastic envelope containing my 20 little modules.  I took one out and hooked it up to the lab power supply.

Feed it around 20mA @ 4V (it does have an internal resistor, so just connecting it across a lithium cell would be fine) and it lights up, leaking quite a bit of red light around the back of the housing while putting a nice bright vaguely-roundish red dot on the wall.

Yes, they're actual lasers, not just LEDs with lenses.  The speckle pattern is a good clue.

For just over two bits per.

Now, should I suddenly develop a need for a tiny laser module (or several), I have some in my goodie box.

Added: These.  Price has come down (!) slightly in the past month.

Another reason elections should be held on election day

Aside from the problem of ballot secrecy, when people vote outside of voting booths....

If you mail in your ballot early, as is the fashionable thing, and then your candidate beats up a reporter the day before the ballots are to be counted, it's too late to change your vote.

Being of a reactionary bent, I maintain that absentee voting should be exclusively for those who have a legitimate reason for not showing up at the polls on the appointed day.  Disabled, deployed overseas, away at college, on a business trip, something like that.  Not: Everybody vote by mail!  Then we won't have to have polling places, and elections will be so much cheaper!

Operation Bug-Out remains on hold, but...

Yeah, still can't commit to a schedule, for family-related reasons.  Such is life.

Still hoping to get organized, pack up, and move this summer.

Anyway!  I went to the local Design2Part show yesterday, ogling the part samples and manufacturing technologies and chatting with people.

There were various engineering-service companies.  Always good to be aware of these; maybe someday I could use their services, or they could use mine.  Or both.  Cooperation is the basis of free-market economics, right?  As I chatted with someone at one of these booths I noticed something: the have an office in the Bay Area... and one in Knoxville.  Hello?

Turns out the guy I was talking to had recently moved to Knoxville (actually, a bit south of the city).  He shared anecdotes about life in the wilds of Appalachia.  Like, rush hour in Knoxville (as I'd experienced last summer: the height of rush hour, and a steady 65 MPH).  The absence of any decent Chinese restaurant (and the locals' discomprehension that Indian, Thai, and Japanese food are not the same as Chinese food).  The politeness of drivers.  And his bewildering first encounter with the Tennessee DMV.  (Seems he walked into the local DMV office, and thought he must be in the wrong place: Where's the line?  Why are these people so helpful?  Why are they not giving me the runaround?  And why are the fees so low?)

Another guy, at another booth, had done the move-to-a-farm thing 20 years ago, and was getting tired of it by now - but he'd been doing rather heavier farming than I have in mind, with various full-sized livestock (I don't figure on keeping critters bigger than the smaller breeds of goat; those are small enough to pick up and carry if they're being stubborn).  He says I shouldn't even consider any brand of tractor other than Deere or Kubota - he has a Massey-Ferguson, and hates it.  That's another thing to file in the back of my mind; the list I already had ran, vaguely, Kubota, Deere, "hey, it comes with the property", and "a neighbor is selling it cheap, and it seems to run".

Also had a brief random chat with a powder-coating guy: I'd seen a couple of YouTube vids lately on home powder coating.  He raised an interesting point: apparently there's some potential for dust explosions, with this finely-divided plastic dust floating around in the air.  I hadn't thought of that, but it makes sense.  It's not like I'm likely to be doing that stuff anyway, what with the need for a large oven.

Oh, and someone was showing off the results of lost-PLA casting.  Rather more successful than The Backyard Scientist's first attempt.  But, then, it probably wasn't a first attempt, was done with specialized investment material and proper equipment, and all that.

And, speaking of pest control

Hey, kitties!  Know what time it is?

(Cats panic.)

Yes!  It's Revolution time!

Line them fleas up against the wall!

The instructions say I've supposed to hold the little bottle to the cat's neck while squeezing it 3-4 times, and then withdraw it in a specific, controlled fashion.

I got almost one full squeeze per cat prior to the hasty departure of the enumerated* feline.

Now they're all hiding.  And it remains to be seen whether Southmoon will give Huckleberry the you're-not-my-brother treatment** again.

 

* Or, wait.  The cat was the denominator, wasn't it?

** Corrected typo: "teratment" - which kind of fits in with the monster theme, though.

All the world seems in tune on a Spring afternoon...

...when we're poisoning gophers in the lawn!

Hmph.

Shortly after I moved in, the back yard developed a gopher problem; the recent demise of the local dinosaur population* allowed the little furry varmints to thrive beneath the grass of the neighborhood park without worrying about the footsteps of frolicking sauropods, and thence to tunnel beneath my back fence.

I planted something called "gopher purge" back there.  I still haven't eradicated the last of the gopher purge.  But... I haven't had any gopher activity since way-back-when.

Well, a few days ago some distinctive little mounds appeared.  This time, in the front yard.  On investigation, I find some mounds in the side yard, too, but nothing between there and the back fence.

Maybe (unlike penguins) they come from next door?  But the neighbors have a well-kept yard.

Anyway, it's time to do my best Dalek impression.  Do I really want to plant gopher purge again?  And in the front yard?

Er.  Wait.

The gopher purge didn't work last time, did it?  'Cause I seem to recall having subsequently bought a little bottle of gopher bait pellets with zinc phosphide.  Which, sometime in the last ice age, seems to have gotten either misplaced or disposed of.

Ergo, off to the hardware store in search of more anti-gopher pellets.  (Either that, or the reptile store for an anti-gopher serpent.  But the local reptile store went out of business several years ago.  And hiring a local kid with an air rifle doesn't seem to be socially acceptable around these parts.)

And then some digging, and some pellet-placing.  And hope that the gophers die underground, and don't end up poisoning local scavengers.

* OK, so maybe it wasn't quite that long ago.

Rebranding!

Seems that Ol' Combover has decided to rebrand terrorists.  The new handle: "evil losers".

Otherwise known as "Very Proper Charlies", though in Dean Ing's version the Press went along with the rebranding campaign.

Will it catch on?  "Splodeydopes" never really did, nor any of the other loser-themed labels.  And will laughing at this appallingly poor career choice affect recruitment?  Maybe if combined with a policy of gathering up all the bits of splodeydopes and wrapping them in bacon for cremation?

Programming-language bubble

Here, via Slashdot: note the part on dead languages.

The same holds for coders weaned on C and C++, says Lions.

“The entire world has gone to Java or .Net. You still find C++ coders in financial companies because their systems are built on that, but they're disappearing."

The entire world... no.  Not now, not ever.

Java isn't even a general-purpose programming language.  It - still! - doesn't even have unsigned data types, so some really basic underlying functionality needs to be implemented in some other language.  Which is to say: C or assembly.  And there are always features needed in specialized software that just can't be written in Java, or can be written only with great difficulty.

You can't nohows write systems software, or resource-critical firmware, in Java nor .Net; they're utterly unsuited to such purposes.

Important lesson: not all programming happens in the IT department.  The hard-core stuff happens in Engineering, or out there in the world of Systems hackers.  And industrial process control.  And those worlds don't speak the same languages as IT, most of the time.

(Further clue: the article doesn't mention FORTRAN at all.  Maybe because Real IT Departments Don't Speak FORTRAN?  But 'twas a big language in its day, and very much still around.  Just not in IT departments.)

Sure are a lot of "experts" who think their own cubicles are the entire world.

Back from the Maker Faire

Oof... about 8 hours on my feet.  Only about 4 miles in all that time, but much maneuvering through crowds.

Ergo, sore feet and sore hips.  Also, it got decidedly warm this afternoon.  And I really should have taken a couple of bottles of ice, so I would have had cold water handy without having to stop at concession stands (there are a very few drinking fountains at the fairgrounds, and the lines were long).

As usual, a fair amount of cool stuff.  Not a lot excitingly new.  There was a lot of kid stuff, which I guess is a good thing, but I gravitated toward the Adult Material, like CNC machinery and fun-with-Nixies.

Much chatting with people.  I randomly mentioned one of my older Evil Ideas to Steamboat Ed; if he shows up at Burning Man some year with a cross between a doodlebug and bagpipes - a flying, noisy abomination that plays MIDI files scored for the pipes - you'll know who's to blame.

I spent way too much money on fairgrounds concession food (and didn't even find any fried artichoke hearts), but ya gotta do that once or twice a year.

Only thing I actually bought at the event (there being no practical way to take one of these home by bus and car, and besides this is altogether the wrong time for me to buy such a thing, and when it is the time, I'll likely want an 1100) was an ODROID-C1+, for evaluation purposes.  Looks like a plausible solution for my cheap-little-embedded-Linux-board needs (it has, apparently, an actual USB host controller, plus an OTG port in case I need it to act like a device for some reason).

Oh, and the Cool Tech of the Moment?  Liquid-resin-type 3D printers using LCD panels to cure a layer.  Does it work?  Um.  It seems rather questionable to me, especially the super-cheap one that uses a user-supplied smartphone to do the exposing.  But... maybe?  Anyway, if it does work, it's awesome.  It's not like I'm ready to buy such a thing right now anyway, but I'll keep an eye on the technology, and make a decision several months from now.  For tech that's known to work, the price of real laser-type SLA printers is coming down.

Little more on that laser module

That one, from a couple weeks back.

I still haven't tried running it up to full power.  But...

Having a few idle minutes, I set it on the workbench, got it to focus tightly on a spot about 3 inches out, and set a handy black object there - happened to be a smallish computer fan.

Then I started dialing up the drive current.  Limit is supposed to be 1.8A (and, yes, the efficiency is supposed to be north of 20%; in-freaking-credible).

The safety goggles made the blue light Just Go Away, but I could see a faint orange dot.  At around 500mA, the dot got very bright indeed, and there came an odor of vaporized plastic.  No, it didn't disintegrate the entire fan, but it took a fairly deep (and small diameter) divot out of it, in just a couple of seconds.

Next up: a sheet of high-quality white paper.  Says on the pack that it's laser paper, even.  As I increased the current, I noticed that the world around the edges of the goggles was getting very blue indeed.  Again, at around 500mA (I was stepping by 100mA increments), the dot got very bright, very briefly, and then dim again.  Power off, and...

Yup.  With enough magnification, I can see a neat little round hole in the paper where the beam had gone through and therefore ceased to reflect.

So, yeah: you can use one of these dinky modules for cutting and engraving.  Not gonna cut metal with it, but it'll certainly do paper, thin bits of wood, various plastics, and such.  And, it'll likely work fine for burning paint off of metal surfaces.

Maybe I'll design a little board that has a laser-diode driver, a couple of stepper-motor drivers, auxiliary outputs to handle things like a shield-gas valve and a danger light, an interlock input or two, a USB interface that appears as CDC-ACM, and some way of selecting between HP-GL and G-code commands.  The hardware is almost trivial, and I already have example firmware to do the ACM side of things.

But not this month.  And, who knows?  Maybe I'll see somebody at the Maker Faire tomorrow already peddling the same thing.

Update: Nobody peddling such controller boards, but there was somebody with a fairly affordable blue laser cutter, built along the general lines I had in mind (except for the focus/alignment mode and the option for using inert shield gas).  Also, there was a decent X-Y platform on display, designed for interchangeable heads - pen, Dremel, and whatnot.  Adding a laser head would be fairly easy, though a suitably opaque / filtered enclosure would still be needed.

Update 2: At around half power, it'll de-blacken black anodized aluminum.  I assume it's bleaching the dye - or maybe vaporizing it? - without damaging the protective oxide layer.  Anyway, I put a thin silver stripe on a stray heatsink, and it didn't take long at all.

Hey, it's spring out there!

Let's ignore the noise for a moment, and go look at owls.

Yup, that's Mommy Owl and Little Fuzzy Gray Lumpy Baby Owl.  I'll probably stop by sometime next week and take another picture.

Also, up at the pond: li'l baby duckies!

Given the timestamp on the photo, these must be from the second group.  (Clutch?  No, before they hatched, they were a clutch.  What's the proper term for a litter of ducklings?)

There are three sets: the first has eleven members; the second, a couple of weeks younger, has nine; and the most recent, five.  So, the Eleven, the Nine, and the Five.  Not to be confused with the Three, the Seven, and the Nine.

One duck to rule them all...

YIPE!

Spotted here:

Another eye-opener for me was learning that “[s]ome vendors implement safety features such as emergency stop (e-stop) buttons in software.” I certainly wouldn’t want to go anywhere near a powerful robot of any sort that didn’t have its big red button connected pretty darn directly to its power source.

(Gibbers incoherently.)

What... the...

Does NO ONE know how to play this game?

Guys!  When you have big, dangerous machinery - or high voltages, or other serious threats to life and health - you use a hardware interlock.

Yeah, there are always demands from Marketing that there be some provision for overriding the interlock.  So maybe there has to be a place to plug in an override jumper (which should preferably be big and red and have dire warnings printed on it).

The emergency stop button is for emergencies.  Like the software running amok.  It needs to work no matter what.

And the things being controlled need to default to a safe state when the controller goes limp, but that's an installation-planning matter... a crane, for example, shouldn't release its load when somebody pushes the Big Red Button on the master control system.

(Wanders off to add yet another layer of protection to an industrial gadget in development.)