exmadscientist

Robots that cannot share sidewalks with humans, including humans in wheelchairs, should be banned from sidewalks. Full stop. End of discussion. They can use the streets proper if they want to.

I'm sure there is some way to formalize that using ADA sidewalk requirements or something similar.

The article is making the case that this is not healthy for society. It is the kind of thing that's fine if 5/100 do it, seriously worrying if 50/100 do, and basically fatal to civilized society if 99/100 people do.

And when I go to the park and have a run, of the 100 people I might see there and on the way, we're closer to 50/100 than 5 or 99. So I think we have a problem.

I think that's an unusual scenario, and I'd ask you to consider that that's probably not the argument I was making.

Most of the dozens and dozens of people I see in daily life sealed away in their earbud pockets do not appear in any way to need to do that. I am certainly not seeing the full picture of every single person's life, but I do not think that every last one of them is incapable of meaningfully engaging with the world.

Being able to do it in the middle of a riot is, absolutely, a hard-earned skill.

But it is, like so many of these things, a skill. You have to practice it.

I think that putting earbuds in and checking out of the world around you is a really awful thing to do as your default in life. As a "sometimes" thing it's fine, even healthy. There's a lot of talk of public transit in this thread. If people do it during riding transit, and not really at other times, I'm fine with that. But so many people have their earbuds in before they leave their front door, every day, every week, and they don't come back out.

And I think that's really, really unhealthy, for them and for the rest of us.

Talking to strangers is a skill. You can practice it! I've made a point of trying to practice, albeit halfheartedly, and even though it's difficult for me, because I like it when other people try to talk to me.

Earbuds stop this practice dead in its tracks. You can't deny that.

The actual "make it go bang" bit here isn't the most potent. (I think I have capacitors here which wouldn't care in the least about this, despite their datasheet ratings.)

If you need to take it to the next level, consider something based on a xenon photoflash driver. These aren't as common as they used to be, but they're still not hard to make. I had to make one of these a while back and ended up using one of those $5 LTC chips but that was appropriate for the situation; there are certainly other ways to do it. This will basically charge a 400V capacitor up for you, which you can then dump into the 5V part. High-quality 5V capacitors will handle small spikes of this. But using a big 400V capacitor will make a big spike, which is not kind to the other capacitor. (I must confess I didn't try blowing up a lot of things on the one I made, but it was medical test gear, not technically a capacitor-blower-uper, and I was on deadline anyway. I also had other, significantly more destructive, equipment available to me should that be the goal.)

The ads showed up when the launcher got a major redesign, and the Google TV (or whatever they call it this week) launcher is a Google product. I seem to remember that nVidia delayed shipping the new enshittified version for quite a long time, so I'm pretty confident Google gets the blame here.

My point, which matches what you've written out in more detail, is that there's supposed to be stuff (resistors) in the cable, stuff which is often not there. There are plenty of these abhorrent cables in the wild. And when you come across one, things get weird, because some sources and sinks deviate from the standard in ways that make them work with these bad cables. Others don't do that. (I believe there were a lot more abhorrent cables in the early days, and thus began the chain of accommodation....)

So unless your cable is known-good, if you are having trouble, trying a different cable should be the first thing you do. It really does often get things working.

Contrarily, if you have identified a naughty cable, it should be immediately widlarized.

The 4.7k "default pullup" is an old-school 5V TTL thing. It works really well for TTL inputs. But CMOS inputs don't really care very much, especially if they aren't toggling or if there's a bit of hysteresis on the input stage (which there often, but not always, is). There seem to be 10k resistors in every design so CMOS pullups often end up at 10k. If power savings are a concern, especially if you need a tie-off more so than a pull resistor, 10k-100k is a perfectly valid range, and I've even used 1M in extreme circumstances.

Usually 5k is a little too weak for I²C. Rule of thumb is that you want to be around 1mA, so for a 3.3V system you start at 3.3k. Generally 1.8k to 3.3k ends up being a pretty common range. More current is usually better than less current, so even at 5V where 4.7k might be OK (if you're even at 5V Vdd these days), going stronger is often a good idea. If power savings is a concern, or if timing's somehow important (did you find another touchy badly behaved I²C device? say it isn't so!) then it might be time to break out the active pullup structures (mostly current source type things). Once this is done and tested it tends to get fossilized, for good reason, so this one won't usually get swept up in a standard-effort cost reduction pass.

The controlling standard is usually 62368, and the target is usually being a "Limited Power Source", which is 60V or less, and 100 VA max.

Right. That phrase "standards-compliant" in the above comments is doing a lot of heavy lifting.

A lot of devices are not actually standards-compliant. Some are close. (This may actually be worse.)

My experience has been that if the source and sink are broken, they are often hilariously badly broken and it is pretty easy to figure out that they are the problem, if not quite exactly what they've done wrong. But if things are flaky and weird and don't really make sense, it's probably the cable. Try a known-really-seriously-actually-standards-compliantly-good cable and many problems go away, even if the source and sink aren't perfect.

(Many sources and sinks aren't standards-compliant because, even though they easily could be, they're trying to work around the other end not being standards-compliant itself, because that's what you've got to do to sell a product. So they're close but not quite there. This is not always ideal.)

I was speaking a little more towards the AliExpress end of things, which is a sadly high proportion of the devices out there. For the midsize CMs and up, you're right, they've got piles and piles of stuff and don't charge by the reel loaded.

5.1k is a surprising resistor value, a lot of modern designs don't really have anything else in that area. I'm often not able to combine anything with it when I'm cost reducing. 4.7k, sure, but there aren't a lot of those either... 2.2k is just not close enough a lot of the time (or ends up as 1k), and same for 10k. So, sadly, it often does stand alone.

How is it an overcorrection to describe their actual behavior? They're still an important part of the protection hierarchy. Nothing else does what a good fuse or circuit breaker does. You just can't count on them to do things they're not designed to do, and must design your circuit accordingly.

That's how it's supposed to work, yeah.

But there is some trash out there in the world. A lot of it, actually.

Some naughty cables work with some naughty chargers work with some naughty devices. Postel's Law in action, I guess?

Usually the best place to fix it is by getting rid of the bad cables. Usually.

The A-to-C cable often does not work because the resistors are supposed to be in there.

So if you are having complete charge failures, try a different cable.

It's two resistors, actually. But they cost $0.0003 each (that's 0.03¢, or just around 3,333 of them for US$1) from distributors. Though there appears to be a bit of a stock crunch right now.

So... yeah.

The bigger issue is not really the parts cost, it's the fact that it adds an extra part to the design that has to be purchased and tracked and assembled and blah blah blah. This is the real reason it often gets left off on the bottom-of-the-barrel products. Many times there is no other use for a 5.1kΩ resistor. And it might not even fit well at the cheap sizes (0603 or 0402), and going down to 0201-capable assembly factory flow just for these two resistors is not going to happen.

> And if USB-C could somehow provide a range of voltages to the motherboard, SFFPC's could be downsized even more

You reeeeeeally don't want to do that. Cable inductance is a big deal, among other issues. You want the main DC-DC regulators on the board, usually right at the load, for the main loads. Most of the PSU bulk is for dealing with mains itself: handling 50/60Hz or mains isolation is just physically large. Getting in secondary 20V DC (or so) from a single connector and then regulating it down on board is pretty much the ideal solution.

(I can't even begin to comprehend the horrors of a USB-PD negotiation involving multiple voltages. It's already the worst standard I've ever had to deal with.* Don't make it worse!)

(* Not hyperbole, it is truly, truly awful. At least things like 60601 are bad because, you know, they're covering lots of stuff like lifesaving medical devices. USB-PD is... holy hell, it is just bad.)

Obviously you ripped it off from my comment a while back https://news.ycombinator.com/item?id=42121502 :)

Seriously though, it's a good format! It works!

> hitting that Zone 5 briefly is a good nervous system reset

I ended up doing this inadvertently earlier this week due to some medication side effects (yay akathisia!) making me want to go outside and just seriously run fast, including up the nasty hill nearby. Which I could, so I did. I'm amazed at how much it seems to have helped, for how simple it was. (Another one from the past, though for different situations: alternating hot and cold showers.)

That's a good design for input overvoltage protection (assuming I've drawn the correct schematic in my head). But it doesn't help against most other fault conditions, particularly anything to do with the load/downstream going short.

Really, if you care beyond "blow the fuse if something shorts", you need active current limiting. For common cases like USB ports, you can buy chips that do it cheaply and efficiently. There are also some textbook circuits, though they each have their pros and cons. No matter what, if you've got a pass transistor or switching transistor that's about to go seriously overcurrent, you have to do something about it with active parts -- fuses aren't going to get it done.

But defense in depth is always a good strategy, and fuses play a key role there. The active circuitry saves the rest of the design; if it can't get the job done, the fuse makes sure nothing burns.

The TPS62140's 30ns propagation delay is not enough to blow a fuse. The first rule of fuses (which many modern engineers do not understand!), is that fuses are not there to save your parts, and they simply will not do that. Fuses exist to prevent fires.

Even a fast fuse is very, very slow compared to semiconductors. I've seen transistors blow up to "protect" fuses. They're for stopping fires and preventing the slaughtering of batteries, nothing more, nothing less.

I think it's not so much about the money as the "When you had to walk into a store... [and] be stuck with it" part. That is, the problem was actually automatic/Internet-enabled updates.

With the physical model you chose your software and it didn't stop working. (It might stop being useful, but that's a different story.) No option to patch later meant a company couldn't ship trash: word would get out and people just wouldn't buy it. (Windows ME, anyone?) Now you can get the rug pulled out from under you on all of your tools, and things "ship" as garbage with a massive "day 1 patch" (and a "day 2 patch" and...) and honestly often never get finished. At least not before they're "retired" and you're "updated" to some dumpster fire that's nothing like what you wanted, and still doesn't even work, and you can't do anything about it.

>aren’t they Microsoft? Couldn’t they order whatever parts they wanted to spec?

Economically and logistically, yes, absolutely. Would it have had positive ROI (stuff like that is expensive)? Who knows, there's a lot of factors to consider, like accessory costs, increased sales, brand goodwill, new markets, whatever. But they could do it if they wanted to.

Culturally, though, this is just not how Microsoft operates. Not for boring accessories like that, anyway. (The Dock team was not where the ambitious-for-promotion people wanted to be.) It absolutely is how Apple operates, though, which is why I mentioned them. Their relative positions in the hardware ecosystem are not an accident.

(However, the technical constraints at that time were severe, and it might not have been technically possible. As I said in a sibling comment, this was the era of Intel's Alpine Ridge (I think that's the right one), and it was a nightmare. I don't know that it was really feasible to do much better, on the timelines needed. Now, after that disaster of a chip was out in the market, everyone else knew what the correct solution looked like, and could build it. But Alpine Ridge had to... salt the earth?... first so we could all move on. Build one to throw it away, but ship it first and poison the market.)

That's actually what a lot of Brother printers do with their default or generic drivers. Except... it's JPEG, not PNG, so you get artifacting. Drives me crazy.

Installing the specific driver like it's 1999 works well, but most people don't bother these days. And thus the world is a bit more crap.

> One of the Surface things split into two parts, the screen (containing the actual computer) and the keyboard. There was something weird about connecting and disconnecting those parts, some motorized docking/undocking mechanism, that caused problems.

Yep, that's the Surface Book (original). I've got one, and mine still works! Somehow.

That detach mechanism is insane. As far as I've been able to put together (I haven't done a patent search or anything, just heard bits from people who'd know), there's no motor involved... it's way weirder. I believe the thing actually heats up a nitinol shape-memory alloy latch in the base so it detaches from the tablet piece. That heating is why it takes a couple seconds. But then reattachment is instant, so it's just something clicking in to place. And you can't reattach immediately, because the base has to cool down (just a few seconds, short enough that you never notice unless you're deliberately messing with it). Black magic!

I'm not 100% sure of any of the above, except the use of nitinol somewhere. That's right, the weirdest piece of the conjecture is the only one I've got hard confirmation of. Like I said, black magic.

Yeah, wake from deep sleep is always one of the weirder bits. It's just hard to do.

Yes, this would have been around 2015. (When I said "Surface Book" I meant the original!)

Docks were bad, bad products in those days. They were no longer the dedicated bulky-but-reliable things of years past, or the modern finally-debugged dongles we've got now.

This was Intel's Alpine Ridge and it was hell. (At least, I think that was the one. Certainly, it was hell!)

I worked with some of the people responsible for the Surface Book, Surface docks, and specifically the Surface Book's dock. These were hardware people (EEs), not software people, and this was after their time at MS. Unfortunately I don't remember specifics (both because it's been a few years, and because I'd probably have to fuzz details anyway), but... :

Docks are horrifying products. Thunderbolt docks are doubly horrifying. They ordered in every single competing dock they could find, from that era's products, and found that every last one was garbage in some way or other, usually fatally so. The Thunderbolt interface in particular, and the firmware that needed to run on that interface controller, was the source of a lot of issues. None of them were particularly intrinisc to the protocol, but the hardware available was junk and the software available was worse. They couldn't really order up a custom non-garbage IC just for a $100 accessory that sells in limited volume. (Apple, however, could and would; they'd also demand to control the whole stack. This shows.)

They were very proud they got the thing working as well as they did, even though they all knew it was still pretty much trash. It was still better than the competition. Which is sad, but what can you do?

(At least it wasn't the Wi-Fi chip. The Surface Book's Wi-Fi adapter was chosen by higher-ups as the same one used in the XBox, presumably for sourcing reasons. It is trash. Again, much blood, sweat, and tears were spilled making it work as well as it does.)

(I also have the exact circuit for the LED that lights up on the charger cable. Apparently it was a big deal, which I find hilarious.)

Most companies didn't, no.

Just because alternatives exist for some people some of the time does not mean Office is worthless, or that buying it isn't rational.

(Though buying it starts to look a lot less rational when things like this happen.)

The other problem with Slack is that it just straight up... doesn't do what you tell it to. I have a set of notification settings that work for me. Slack goes ahead and just does something else, and you simply can't fix it to do what it's told. (Or couldn't, anyway; I've been off Slack for a while.)