summa_tech

It feels like the concept faded with the advent of large VRAM and fast fill rate graphics accelerators. I remember old X Window System workstations supporting multiple concurrent windows with different color depths and modes. The hardware would compose windows from memory during display scan-out, all to save VRAM.

I think that's what "STABLE ONLY" clickable text filters by.

Hot water, good dentishtry and shoft lavatory paper.

Then you take an illegal instruction exception, and you have a choice to request a rebuild, patch it, or emulate it. (Yeah, sometimes the vendors just don't cooperate.)

Incidentally, emulating opcodes is quite often practical (unless the performance must not be affected), and is greatly helped by having the plainest, cleanest instruction encoding possible, and a well designed system register & exception architecture.

One hopes that a hypervisor would not expose hardware control registers directly in the first place, except ones deliberately designed for virtualization support.

Otherwise, the guest is running effectively at the same privilege level as the hypervisor (that's useful sometimes, but probably not intended in most applications).

I, too, had wondered; this seems particularly common in the US. My best theory is that in rough handwriting, n and u/μ can look pretty similar, and everyone sort of agreed to only use u to reduce ambiguity.

Laminated wood veneer for legs, plywood for seat. Not as disposable as the eternal LACK, but also not bent wood.

It certainly tarnishes the shine to have a per-OS-version table of offsets to patch ;(

It always feels a bit like lost magic. But at the same time, it's also something that was only enabled by the very high determinism of these old home systems. The design relies on having fixed RAM locations, no multiprocessing, etc.

Incredible to find out that typing the paper program would not have worked, though. And in such a disappointing way no less.

Excellent explanation.

I'd like to add that no light source can lie outside the horseshoe of the CIE xyz diagram: pure wavelengths are points on the curved line, everything that mixes them moves towards the inside of the space. So you're stuck with triangles that fit within it.

Well, it's complicated. As I understand, one of the polio vaccines - the oral one - has an unusual quirk.

The live virus used in it can reproduce and spread in low-vaccination communities. While the vaccine version of it will not cause paralysis, it can and occasionally does mutate back into a pathogenic variant.

So we're sort of maintaining a reservoir of polio, really.

Imagine a power splitter + phase shifter that produces a correct phase shift for each element in a phased array to produce a directional beam from one radio transceiver.

Now this clever arrangement, instead of having only one radio transceiver port, has multiple. And each of those ports corresponds to a different set of phase shifts, producing a directional beam at a different azimuth angle.

And because this is an entirely passive device, it's linear, and all ports can be active at the same time (principle of superposition essentially). So you can use a single phased antenna array to serve multiple directional beams at the same time.

Right! I think a lot of people, who have not done a lot of "things you can kick" engineering, have a very romantic view of it. Especially the relationship with whoever is nominally setting the goals of the project.

The physics works perfectly, of course. But physics is only a third of the constraint in engineering. The other two thirds are project goals and convention.

Project goals are horribly underspecified, every time. It's incredibly rare to be given a project that is completely constrained on that side, and if you do get one, most of the time it's physically impossible to achieve. This is because the people who write those specifications not doing engineering, they're doing marketing or sales or just had a cool idea. Sometimes that can even be the engineer themselves :-) So it's up to the engineer to fill in the gap, and they do it with experience and a sense of aesthetics, of sorts.

Convention is what constrains the physical possibilities of engineering to the practical. Yes, you can build anything and make it work, possibly even better than what everyone else builds. But you will have to invent and construct a lot of new technologies before you can build your perfect mousetrap. So, you settle on standard components and build a decent one instead. But this introduces a gap between physics and engineering, too. A bit of no-man's land that you can reach into to produce truly great results. But it's up to the engineer to know when it's worth it.

As a matter of fact, Nature does regularly publish papers about wetting properties of water. In fact, it just published one last week, from Nature Physics:

https://www.nature.com/articles/s41567-026-03299-z

Scientists find more or less everything very interesting, even (especially?) things that are supposedly self-evident. You can both make a big splash disproving self-evident things, and much can be learned from it.

If you can read more than one language, try reading translations into two or three different ones. It'll give you a different view of a book you enjoy: the translations will all have a different feel, in my experience.

On most modern Apple SoCs, including these two, there's an IOMMU dedicated to the USB complex (called the USB DART, perhaps DMA Address Remapping Table).

However, Boot ROM on these two chips does not program it; Apple probably felt that it was an unnecessary technical risk to do so. The Boot ROM code was well-verified and unlikely to contain bugs like buffer overflows. But nobody expected a hardware bug :)

Sure, StarCraft is kind of a hybrid when you think about it. The guaranteed-hit model, the extremely simplified low vs high ground approach to determine if a shot is possible, etc. are pretty deterministic. But in more complicated situations it's still a lot less predictable than chess. Even the examples you're giving can only happen probabilistically outside very early game.

But I'm thinking about TA-style games, the topic of this discussion, which pride themselves on large armies. Though, to your point, early game of Supreme Commander is also quite chess-like, because of how restricted the set of opportunities is.

Chess presents a comparatively small and, importantly, discrete set of choices at any moment. So it feels like it's a solvable logic puzzle: like it should be possible, at any moment, to make an optimal move. You can predict if you lose 2 or if you lose 3 pieces because of your next move, and you're expected to use this knowledge. The strategy of chess is about perfection in every turn.

RTSes present continuous, large choice spaces. So it doesn't really feel like as much of a logic puzzle, and perfection does not appear to be within ones grasp at every moment. Whether you'll lose 4 or 6 of the T2 fighter-bombers is not relevant. The strategy of RTSes is strategy of big plans and high level abstraction.

He's basically repeating his mistake - underestimating the relevance of technological progress - from 28 years ago, except now it's explicitly in service of his political bias.

For your information: Paul Krugman is a Nobel memorial prize winning economist. He used the publicity of his award to become, essentially, a political commentator, including an opinion column in the most important American newspaper of record, the New York Times. He's not a random commenter on a website, without any ambitions of relevance. He uses the aura of being an eminent scientist to give his personal opinions a veneer of respectability that they perhaps do not merit.

It's difficult to consider Krugman's takes seriously after his very flawed 1998 predictions. Perhaps he's uniquely poorly suited to understanding the role of technology in economic development, and is best described as an economist with a very limited outlook outside his narrow discipline?

https://www.snopes.com/fact-check/paul-krugman-internets-eff...

It became obvious / accepted wisdom that a moderately successful startup exit is the only way to have a decent future as a living person.

This used to be only one of many paths available to a nerd, but now: (a) academia is dead thanks to overly competitive publish-or-perish set-up (probably the biggest loss of the three), (b) corporate jobs do not pay enough to safely survive downturns that leave you jobless for extended periods, (c) government jobs have been made even more onerous and even less paying in real terms.

So everyone has to become a self-promoting, trend-chasing startup-founder type. Even if you don't found a startup, you have to be always ready for a new "business opportunity".

Neat! What do you think about adding a "-2, -1, 0, +1, +2" agreement scale to each quote and showing the average instead of votes?

I think many of those are pretty subjective, and maybe not always right for everyone or for all time. But there are certainly going to be some universal pearls of wisdom, and neither of us can - by ourselves - tell which ones they are.

Once you understand how a program works, get someone else to write it for you. Then, you will quickly find out your understanding was insufficient.

I don't think I've seen anything sufficiently RAM-like. The classic sense amplifier architecture tends to make this impractical. I guess modern Flash can store a few levels but that's a far cry from actual analog storage.

For a while, you could get things like bucket-brigade CCDs for analog signals (used for reverbs and suchlike). They're still made in small quantities, I think, by boutique operations like Xvive.

Also, there was the ISD ChipCorder, which was actual analog Flash. (Current devices are digital, but the old ones were for a while sold as "MLS ChipCorder" by Nuvoton.)

Tubes can also just be very _clever_ in a way that transistors generally are not. For instance, counting tubes that would contain a decimal counter in a single glass bubble (that's quite a few transistors even in TTL, and about twice as many in CMOS). Multiple approaches to building such tubes existed. This is one:

https://lampes-et-tubes.info/cd/cd053.php?l=e

Or the complicated and impressive storage tubes, that would fit 16 kbits of RAM in a single CRT:

https://lampes-et-tubes.info/sc/sc022.php?l=e

By the way, this website is one of my favorite finds on the Internet and very long-running.

Pretty good detail in this article! But what really surprises me is how some ideas just keep coming back.

When I wrote a binary translator, I ended up having to keep a translated return stack to optimize RET opcodes. That put me in exactly the same position as the Win16 kernel with regard to having to patch pointers (in case of Win16, just the segment part) on stack.

Of course I did not have the benefit of my guests calling a lock function, so I ended up having to run a garbage collection operation to determine which pointers are in use & take exceptions on now-invalidated segments. Lots of extra work that Windows didn't need: it's nice to be king :-)

That was a fun site to browse. I really enjoy fixing / hacking on non-disposable equipment (lab, test, optics, etc.) and there are some well-done write-ups in there.

USSR, yes. But the ISS was launching during a time when USSR no longer existed and Russia was fairly isolated. Hence, "obviously": US at that time had many close allies, but Russia had only a few, and not as technologically advanced.

I think it's an attempt to express that the station consists of only two segments: Russian (ROS) and US (USOS), but the US invited its allies to work together on its segment. So parts of the USOS are made in Europe, Canada and Japan, and generally lifted to space by the US, usually on the Space Shuttle.

(All this was pretty lucid of the US, but obviously the Russians did no such thing on their side. The Japanese even managed to get an ISS resupply mission launched on their own vehicle, which is no small achievement, and the ESA did a bunch of good science. And what would space be without the Canadarm :-)

Good point. Or repair rows (like Virage/Synopsys STAR).