Ask me a question about a specific realistic problem (ie, not "how do I replicate this behavior of PGP", but rather "how do I solve this real-world problem") and I'll give an answer (or someone else will).
I think I described (though perhaps too briefly or not clearly enough) the very specific realistic problems?
I'm somewhat amused that every time this kind of discussion comes up, the answer is "you are holding it wrong". I have a feeling the world of knowledgeable crypto folks is somewhat detached from user reality.
If a single tool isn't possible, give me three tools. But if those three tools each require separate sets of keys with their own key management systems, I'm not sure if the user's problem is being addressed.
It's because the phone design needs the battery to help stabilize the voltage under load. As we know, digital devices can nearly instantaneously change the amount of current they consume and thus require layers of energy storage to accommodate the transient currents quickly. However, the changing current consumption doesn't just happen briefly. It sometimes continues to ramp for more than milliseconds (a glacial time frame for modern electronics). Thus generally every component in the power supply network of a design serves some stabilization and filtering role, including the batteries.
It appears that in this case, as the original battery aged, its internal apparent resistance (ESR) increased beyond the original design expectations, to a point where the phone won't work when plugged in to a charging cable because despite the charging cable most likely being able to deliver sufficient power at DC, it had too much impedance to supply it quickly enough. When current is demanded from a source that has too high impedance to supply it, the voltage drops. This will result in significant voltage ripple to the power supply of the digital circuits, which can cause logic to not function correctly.
Adding a large capacitor basically replaced the filtering and stabilization role of the original battery.
Interestingly people often intentionally remove capacitors for side channel measurements and glitching attacks.
Fascinating, thanks for explaining! I had assumed it was just that capacitors were easier to get hold of than batteries, and that the author was just putting up with a reduced "battery" life as a result. It makes sense to replace with capacitors if they're just using it for always-powered static applications -- probably with much lower fire risk to boot.
There are modular dot shaped led matrix blocks that are basically LEDs under a cast piece of resin that guides light. They're tillable and you can drive them with an FPGA and a smart shift register based constant current driver. They're generic so you can look around online.
However this is assuming your installation will be reasonably large. If it's too big, I recommend making your own array out of discrete LEDs. They sell LEDs with a built in milky diffuser that are suitable.
I completely agree. I can't handle watching his videos for long, for similar reasons.
However besides the personal dislike, I think its worthwhile to stop giving so much merit based on advertising "open source" or "effort" or "presentation" etc, because frankly many of these YouTube "makers" and the "maker community" are misguiding a lot of people to make bad designs and waste time and resources. People ought to value correctness and quality a bit more, lest our things become even more enshittified than they are now. One would think that hobbies would be a refuge from disposable low quality shit... yet we get RPi Pico et al (which are arguably getting less shitty but still laughable compared to actually good MCU products) and the people who claim to "out do the big corp" by using a Raspberry Pi with an SDR dongle and saying they achieved $50000 of capability with $60 in parts..
Case in point, the Opulo PNP systems are significantly overpriced and have amateurish mechanical as well as circuit design that are worse than cheaper systems like Pandaplacer in terms of reliability and performance.
Explain how RP Pico (rp2040) is "low quality shit "compared to "actually good MCU products" (which are those supposed to be?)
I agree that Opulo PNPs are overpriced though, but I'm sure people getting these are aware that it's just a bunch of 20x20 aluminium profiles, 3d printer mgn rails, basic DC pump, etc and parts-wise there's nothing to justify the price, but they get them anyway because of entusiastic community engagement and support aspects - most importantly - in English. And it probably works just fine for the small scale projects they are used in.
I'm referring to their collective effort in MCUs, including RP2040 and RP2350. There are a bunch of issues that are now addressed but permanently makes me distrustful of them especially when combined with how uninteresting the hardware are
- Broken ADC design on RP2040 with nonlinearity at certain codes (and they're not fixing it)
- Shipping chips with exact part number of inductor and specific DCDC layout requirement (like come on, the Chinese are advertising zero decoupling capacitor required and you can route the USB right under the chip in funky shapes and everything "just works".. meanwhile RPi is doing this)
- GPIO current leakage (fixed with a stepping but I would hate to be those who bought a reel of the earlier stepping)
"Actually good MCU products" in my opinion are those with at least a reason to exist. For example the ubiquity of STM32, the radios of ESP32, the high compute of i.MX RT1172, the cheapness of PY32 et al, the low power of Ambiq chips, the reliability of Atmel/Microchip, the USB3 on CH569, the potential true MCU-level-SoC-capability on AG32, etc. When compared with these, RP chips are frankly not innovative at all (PIO does not unlock much actual capabilities besides party tricks). Combined with the general culture of people hyping RPi Pico chips, it results in a culture of ignorance and hype.
Erratas alone aren't a big deal, but the fact that they're happening with such basic things and for no innovation is not a good sign. We shouldn't give RPi a pass just because "it's the good old RPi that we know"
Stm32 chips are plagued with all sorts of issues and hardware bugs that are very easy to run into. In comparison rp2040 has surprisingly few major defects apart from its ADC implementation.
I see no mention of exact part number of inductor requirement in their hardware design guide, are you making shit up now? They are somewhat more particular in oscillator selection, and unfortunately don't include factory trimmed RC oscillator like most MCUs do these days.
> PIO does not unlock much actual capabilities besides party tricks
Ok, so you've no idea what you're talking about.
RP2040 is widely used in many projects because it has insane bandwidth for MCU in its price category. It can do 4 x 32bit reads/writes per cycle (if those ops are spread across 64kb x 4 memory banks), at 200mhz base clock, which gives theoretical maximum of 3.2 gigabytes per second bandwidth. That is pretty crazy.
This enables you to interface with or easily emulate many highspeed interfaces. And do things like 24ch 400mhz logic analyzers and similar. And this is what they are commonly used for (emulating memory cards, etc)
And that's a 60cent MCU. In this price range MCUs don't have 264kb of SRAM and 133/200mhz much less with two cores, that can push anywhere remotely this insane amount of bandwidth.
rp2040 additionally has human friendly and readable documentation, with truckloads of examples, and API that's pleasant to use. (can't exactly be said about stm32 ref manuals and APIs).
While it is not perfect (rp2040 ADC, and lacks encryption), some of those shortcomings have already been addressed in rp2350, with double sram (520KB at this price point!), floating point, even more PIO, more improved DMA channels and so on.
While cheap py32, gd32, apm32, etc are cool, but they just generic arm32 m0/m4.
A 10 cent 24mhz m0 puya with 3kbs sram, isn't particularly impressive when put next to 60cent rp2040 with 80x sram, etc
> Combined with the general culture of people hyping RPi Pico chips, it results in a culture of ignorance and hype.
You haven't opend an errata sheet of stm32 chips even once and you talk about ignorance.
rp2040/rp2350 are unironically one of the best MCUs on the market (esp. in their niche), both in documentation/API and price/perf and features/flexibility in doing highspeed interfaces/bandwidth.
I have read the docs, and like I said the point of STM32 is ubiquity. It's not a great design in other respects but it was once ahead of the envelope and that made it ubiquitous which made it king for longevity. There is no room for another "king" on that throne. Especially counting all the clones of STM32, it is basically a forever design.
Comparing a 60 cent chip to a 10 cent chip is itself crazy work. That's like a whole three stratums apart in terms of capability. Dammingly, you are forgetting about the cost of the external flash that it requires, when program flash is the main cost of MCUs. It shows you don't have much experience with this stuff.
> I see no mention of exact part number of inductor requirement in their hardware design guide, are you making shit up now?
They literally had to "work with Abracon to create a custom 2.0×1.6mm 3.3μH polarity marked inductor" like wtf
Besides how it looks like you weren't one of the early adopters (since RPi shipped one abracon inductor with every one RP2350 for a bit), you also clearly haven't designed a board with the chip in question.
> theoretical maximum of 3.2 gigabytes per second bandwidth. That is pretty crazy.
This is what I'm talking about, like honestly what capability does that unlock for you beside party tricks? Can you name anything meaningful beside "logic analyzer" and "some memory card?" Even disregarding that, what can you do with such thruput if you are bottled by USB 1 speeds and a core without FPU? It doesn't come close to being able to do interesting things like LVDS ADCs or actual high speed memory interfaces because of the bit width requirement, yet people will go into a frothing frenzy should you dare insinuate that RPi Pico might be kinda useless
> rp2040/rp2350 are unironically one of the best MCUs on the market (esp. in their niche), both in documentation/API and price/perf and features/flexibility in doing highspeed interfaces/bandwidth.
As you might surmise, I disagree. Go make some actual projects instead of "reading the docs" all day (though I must admit I do the same). Also, it sure looks like our definition of high speed differs by a wide margin
> Dammingly, you are forgetting about the cost of the external flash that it requires, when program flash is the main cost of MCUs. It shows you don't have much experience with this stuff.
If you had any experience "with this stuff", you'd know 16mbit of QSPI flash (compatible with rp2040) costs 7-8 cents in volume. 64mbits 12cents or less. And would calm your tits. It is okay.
> Besides how it looks like you weren't one of the early adopters
If you had any experience "with this stuff" you'd know better than to buy reels of mcus on rev1/rev2 that haven't been on the market for atleast a year or two.
> bottlenecked by a core without FPU
Why would lack of FPU impact bandwidth?
Lack of FPU is non-issue with fixed point math in most cases.
> I have read the docs, and like I said the point of STM32 is ubiquity
And yet during chip shortages, rp2040 were one of the few MCUs without stock issues or crazy prices... in fact, I've never seen it out of stock. STM32 on the other hand... ouch. Fun times!
>This is what I'm talking about, like honestly what capability does that unlock for you beside party tricks?
So every capability and use-case that doesn't tickle your zoomer sensibilities is a party trick?
QFN packages would not benefit much from this (you cannot make much more than a basic breakout board, whose same purpose is better fulfilled with one of those SMD adapters from aliexpress)
And regarding high-speed digital buses... are we being genuine here? Just the fact that you cannot have meaningful design over ground return paths with this thing makes any moderately fast digital link unfeasible. Best you'll be able to manage is regular speed SPI (which also does not need a board like this), you can forget about RGMII, ULPI, LVDS, MIPI, SLVS-EC, or anything else for that matter.
The post I replied to said "If I'm doing vias, I'm nearly finished with prototyping". You're not if you're using a QFN switcher which needs heat dissipation via the center pad. There's lots of cases of prototyping where vias would be handy.
> you cannot make much more than a basic breakout board
Except, you know, all the supporting circuitry, connectors, maybe microcontroller and JTAG header which could be put on instead of bodged together with random wires -- exactly the problem this is targeted to solve.
> Just the fact that you cannot have meaningful design over ground return paths with this thing makes any moderately fast digital link unfeasible.
You can with a 4-layer version, which is brought up in the video as one of the obvious improvements to make/try, and you would need/want the vias at least to route the other signals around your high-speed traces.
I feel most people would unless you use some Hard IP for the interface. Like you don't bit-bang PCIe when you feed a wide AXI stream at a few MHz into the PCIe block where it get's serialized and put onto the lanes at the signalling rate (multiple Gigahertz, depending on generation).
I see your point but, they're really not selling much more than golf carts and drones. If they go all-out with selling their actual military hardware (which they have a large stockpile and production capacity of), it would be get much more difficult for Ukraine to keep up the balance without increasing support from the west.
It's really quite interesting to see China being labelled as imperialist mean while the western powers have been colonizing and meddling in all kinds of affairs for generations... (see Operation Northwoods as one example)
The entire point of being able to mention past mistakes is for future generations to be able to learn from them and avoid making the same mistakes. It seems, in recent times, that while this liberty is "afforded" to US/Europe, they're not able to use it effectively, if at all. Meanwhile, even though the Chinese might not be able to talk about their mistakes publicly, it seems evident from their progress and events that they have not forgotten them, and that it is in their minds, at the very least.
Edit: Not to mention, looking at how your current president is going after Canada just because of an ad, don't keep your hopes up on US citizens being able to "mention" things either.
> "Corporations," in this context, is just another way to say people.
No, I think its referring more to the systems that describe how the group of people behave. It is an important distinction.
Also, the idea that effective and lasting change requires significant personal sacrifice and enduring hardship is yet another thing that corporations and politicians would like you to believe. It's great for causing inaction through human nature. Its effectiveness can be seen in anti-riot measures like tear gas or less-certainly-lethal munitions, asking people the question of "do you believe enough to endure THIS?" It's a rhetorical question.
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