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It’s not a rare edge case. Not at all. A lot of WLCSP parts will go way out of tolerances if exposed to direct sunlight. The thing that makes xenon flashes exceptionally adept at triggering malfunctions is a combination of their high intensity ant their exceptionally fast rise and fall times.

This vulnerability, where present can be (and is commonly) exploited in alarm systems, access control devices, and other electronics that may face adversarial incentives. Light-protective covers are a very standard feature in construction of any kind of critical device that uses WLCSP parts.

In the case of the raspberry pi, the fact that it is a hobby device is a pretty good excuse for leaving the devices unprotected, but I definitely would have included the fact that the design incorporates WLCSP parts in critical roles and that the PCB should be in a case if being used in mission critical applications, since presumably, designers integrating RPI are less likely to be experienced board-level engineers.

My comment about being a hack or a noob really wasn’t meant for the RPI designers, though I can see how it would be easy to read it that way. I may be a bit of a literary hack, myself lol.

Xenon flashes are also fairly broadband and emit UV that should be mostly absorbed by the glass/coatings, but maybe some still gets out at just the right energy level to flip a bunch of transistors. LEDs are comparatively very narrowband in the visible region.

> You’re exaggerating. WLCSP photosensitivity is an uncommon phenomenon that requires a very strong and specific light source

"In 1967, Dawon Kahng and Simon Min Sze at Bell Labs proposed that the floating gate of a MOSFET could be used for the cell of a reprogrammable ROM (read-only memory).[3] Building on this concept, Dov Frohman of Intel invented EPROM in 1971,[3] and was awarded U.S. patent 3,660,819 in 1972. Frohman designed the Intel 1702, a 2048-bit EPROM, which was announced by Intel in 1971.[3]"

"The programming process is not electrically reversible. To erase the data stored in the array of transistors, ultraviolet light is directed onto the die. Photons of the UV light cause ionization within the silicon oxide, which allows the stored charge on the floating gate to dissipate. Since the whole memory array is exposed, all the memory is erased at the same time. The process takes several minutes for UV lamps of convenient sizes; sunlight would erase a chip in weeks, and indoor fluorescent lighting over several years.[8] Generally, the EPROMs must be removed from equipment to be erased, since it is not usually practical to build in a UV lamp to erase parts in-circuit."

https://en.wikipedia.org/wiki/EPROM

I remember placing stickers over EPROM windows to protect them from sunlight.

Deep deep archived memory that one...

Hehe.. remembered an optimum wavelength ~255nm (and indeed - Wikipedia says 253.7nm. Close enough :).

> sunlight would erase a chip in weeks

Been there, done that. When I wasn't in a hurry, I'd stick some EPROMs in a foam & put 'em under a window. Usually took a bit under 3 weeks. But no point trying in the midst of winter; probably works but could take months.

Loved those windowed ceramic packages. Especially microcontroller parts like (iirc) 87C52. Lovely patterns to have a look at with magnifier.

When I was a kid I used to spend hours exploring the surface of windowed ICs with my field microscope. I have a weird association of microchip architecture and the depictions of the surface of the “Death Star” in Star Wars. I think I used to imagine I was flying over the surface of the chip lol. I was slightly saddened by the electron microscopy of smaller node sizes as time went on, the features became more globby and a little less beautiful.

> Most PCBs aren’t distributed to consumers as bare PCBs, so this issue rarely appears to end users.

In terms of hobby/maker electronics, embedded systems, etc., which the Raspberry Pi falls under, yes they absolutely are. The entire Arduino ecosystem is like this.

Raspberry Pi does indeed have users for whom it's in the same category as things like Arduino.

But it also has lots of users for whom it is simply a cheap computer to plug into a screen / mouse / keyboard, people for whom the only interesting things about the hardware are its price and size.

(I've no idea what the ratio is, but I would guess the majority of customers are the latter type; though possibly not the majority of Pi's sold, since the former group contains people much more likely to buy multiple devices, whether someone like me who's bought a few for tinkering with, or someone actually doing something interesting and needing either 100s for their own project, or 1000s to go into something they're selling.)

So what you said is true for some, but far from all, Pi consumers.

During the pandemic, there was a noticeable shortage of Pis on store shelves. Comments by hobbyists indicated that the existing supply was being snapped up by small-time manufacturers who had designed commercial products around the Pi as a base, and end-users weren’t receiving priority or first dibs at them.

Raspberry Pi themselves said they were prioritizing businesses over retail consumers at the time; businesses need stuff to sell to remain viable.

That’s all well and good, but Raspberry Pi had been positioned in the market as educational, entry-level, easy to understand and ideal for children learning Linux, Python, or electronics.

Perhaps some kids can circulate a list of those commercial products incorporating a Pi, and campaign to liberate and repurpose them. Win-win?

"campaign" lol. I can remember some of my youthful "campaigns" to liberate useful technology... I cant say I find them recommendable.

Doesn't the article say, in the second paragraph, "...he’d stumbled onto something unprecedented."?

> I know there’s something about the Raspberry Pi that makes armchair quarterbacks want to find ways to call their engineers “hacks” and “NOOBS”

Because they are hacks and noobs? Who puts a WLCSP part on a board which is more commonly zip-tied to a piece of wood than it is placed into a case, and is more likely to be driving some wild contraption shooting RF and UV and god knows what else everywhere, than it is sitting inside some nice little commercial device like an office labelmaker?

Their hardware is almost always immediately superceded by cheaper, faster, better boards because they're not trying to give Qualcomm blowjobs clearing out shitty SoCs nobody wanted to buy because they were buggy, underperformant, overpriced, or all three...and they don't have the market advantage of everyone buying whatever garbage they spit out. Other companies have to start on the back of their heels so their products can't suck.

Their hardware designers are inept with every generation of every product they've made having issues and/or promised features not making it into production.

Their QA is non-existent despite seeding test boards widely where either they're not catching problems before doing into production or they're intentionally not fixing stuff because it would increase their costs and they know people will just snap up whatever garbage the Pi Foundation ships. The problems are so bad that you have to ask how they even got past internal testing and validation.

Seriously: if a bunch of college EE students worked for a semester they could probably build a better product.

Each generation of the Raspberry Pi has had basic hardware design flaws showing that their hardware engineering was not up to the task of producing the dominant hobbyist (and increasingly commercial/industrial, somewhat frighteningly) SBC.

Then they fucked up the RP2040, a wildly simpler product. When when they released a revised version that fixed the ADC issue, they fucked up GPIO. How do you fuck up GPIO and not notice?

I don't know who the Raspberry Pi foundation employes as hardware enginers but whoever their head of engineering is should have been fired a long, long time ago.

So what should I buy instead of the RPi Zero 2 W, that's faster, cheaper, and better?

Ah, there it is. As a long-time Pi lore aficionado (is there such a thing? or am I just obsessed with a company that the CEO amusingly describes as "the other fruit computer company"?) in any thread that gets traction there's inevitably a screed posted along these lines:

* "I'm mad because there's not an open source hardware/software/gpu/schematics/BOM" so I can't hypothetically make a clone of it

* If (1) above is not the motivation, then it's because there's some specific use-case that doesn't work that the rage-post precipitates, and crucially - includes zero links to bug reports or a log of efforts that the OP has attempted

* "All the designers are idiots because minor fault X is indicative of systemic failure Y" - with no supporting evidence

* General assertions that all these faults are catastrophic and should bankrupt the company (often conflated with the Foundation, which is a completely separate legal entity)

There's been about 80 million units sold so far. They must be doing something right.

Disclaimer: I own RPI.L stock. It's one of the few tech stocks on the LSE that have actually performed OK and not tanked since IPO.

When you make something that will be mass produced 80 million times, you have a fundamental duty as an engineer to absolutely minimize the amount of negative externalities that will be experienced by people that come into contact with the surface that you have inflicted upon the world.

“Real” engineers understand this and that is why they are often seemingly irrational about their selective attention to detail.

Hacks and noobs are just unintentionally dumping plane loads of gum wrappers over our cities, nominally increasing human misery by tiny amounts without even realizing it… but in a population of billions, and more transistors than grains of sand on the planet, the overall effect is cumulative and significant.

That’s why people that understand their civic responsibility to do their job to the best of their ability look upon hacks and noobs with concern or sometimes active hostility.

Unfortunately, people that understand the responsibility aspect of engineering are few and far between. Hack together whatever you want, and Have fun doing it… but if your actions are going to create millions or billions of objects that millions or billions of people are going to somehow interact with or be exposed to the effect of on a daily basis, you have a deep and fundamental responsibility to make sure that those interactions are at the very least completely and utterly benign. This applies to software as well as hardware.

Introducing even a tiny spark of misery into the world that will be experienced millions or billions of times makes you a world class asshole that has actively contributed to making the world a shittier place in a significant way. It’s like you just dumped a c130 load of gum wrappers over a city from high altitude.