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kees99on Reverse Engineering All the Raspberry Pis

> not offering (...) GPIO/I2C/SPI/Serial

Nearly every "old PC" does offer built-in easily accessible I2C - as "DDC channel" of a monitor plug - VGA, DVI, HDMI, DisplayPort - all have it. Linux exposes those as regular /dev/i2c-*, so any I2C software that works on a RPi or other Linux SBC, will run with those too:

https://web.archive.org/web/20120903090802/http://www.painty...

kees99on How to trigger a command on Linux when power switches from AC to battery

You'd probably want to do the filesystem unmount dance first:

  echo 1 > /proc/sys/kernel/sysrq
  echo u > /proc/sysrq-trigger
  dmesg --follow \
  | grep -qm1 'Emergency Remount complete'
  echo o > /proc/sysrq-trigger

...least putting a bit too much trust in ext4/btrfs/zfs journalling.

kees99on AI is killing the web – can anything save it?

It's not just SO. Pretty much every site running git-scm, has caved under pressure from AI bots and is now inaccessible without javascript - kernel, openwrt, etc, etc...

https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux...

https://openwrt.org/

kees99on Twitter's new encrypted DMs aren't better than the old ones

Gold-plating of contact surface of electric connectors is indeed genuinely useful, on account of preventing contact oxidation.

Assuming good contact in connector(s) is achieved, gold-plating does not further help with high-speed signals. What matters here - is wire/cable itself, specifically, tight control over where conductors are relative to each other and insulation, so that impedance is well matched throughout, cross-talk is minimized, etc, etc...

kees99on Twitter's new encrypted DMs aren't better than the old ones

A lot of quack tech is technically somewhat useful. Oxygen-free copper, occasionally used in "audiophile" cables - technically is a better electrical conductor (compared to regular copper), by a whooping low single-digit %.

Exact same effect could be achieved by making conductor that very same single-digit % thicker. Which is an order of magnitude cheaper. And ohmic resistance is not that important for audio-cables anyway.

kees99on Faulty 120W charger analysis (Anker GAN Prime) [video]

Blind vias, yes. Also - compared to average 4/6-layer PCB - thicker copper layers, thicker metalization of vias, more layers, thicker board overall.

kees99on Mullvad Leta

Yes, rootfs-on-NFS also qualifies as "diskless", I stand corrected.

kees99on Mullvad Leta

Diskless (edit: with OS in initramfs) is indeed a golden standard against local persistence, but requires quite a bit of extra RAM - few GB for "latest Ubuntu LTS".

With regards to preventing accidental persistence, disk with only dm-verity partitions is as good, with extra advantage of only adding a little bit of extra RAM usage (/tmp, /var/run, ...)

For that matter, even something as sloppy as booting with rootfs wich can't be remounted rw (iso9660, squashfs, etc..) and is the only mounted fs, is also perfectly good against accidental persistence.

kees99on Faulty 120W charger analysis (Anker GAN Prime) [video]

The opposite. Planar (PCB-based) transformers are more expensive to make, but allow much tighter control over where wires and insulation go.

A properly designed one will be significantly more compact for the same power rating (compared to wire-wound one).

They are quite common in high-wattage high-reliability power supplies like modular PSUs in rack-mount servers.

kees99on Booting the RP2350 from UART

Some wifi controllers can also boot like that. In particular ESP8089 chip that shipped with some android tablets circa 2012-2014.

Later, Espressif took that chip, modified bootrom to be able to boot from an SPI flash as well, and marketed that variant as "ESP8266". Serial bootloader was kept as a debug/programming interface, and that was inherited to ESP32 and later chips. All of which can boot directly from serial.

kees99on All roses were once yellow

True that. Umberto Eco was a genius.

kees99on Greek Woman Divorces Husband After ChatGPT 'Predicted' He Would Cheat on Her

No way a human fortune teller would say something like that in their right mind.

Same as with fortune cookie quips, any "prediction" will be something that sounds deep and intriguing, but always vague enough to be non-falsifiable.

Otherwise, client will come back and confront fortune teller about it. And human one knows it well enough to avoid making an unnecessary headache for themselves.

kees99on All roses were once yellow

Depending on your definition of "rose", this statement is potentially false.

TFA mentions "genus Rosa". If that's the definition, this is false. Wild R. canina is pink:

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

kees99on Pakistan's solar revolution leaves its middle class behind

> only when grid is powered, solar systems export power to the grid?

Worse yet. When grid is down, some grid-tied systems will not allow any local power use either.

Few years back, nearly all grid-tied inverters had this problem. Now situation is slowly improving, with "grid-interactive" systems which do allow local use of solar power with no grid.

kees99on How to quickly charge your smartphone: fast charging technologies in detail

> Xiaomi HyperCharge requires an original Xiaomi cable and charger because the USB-A connector used includes an additional physical contact—five pins instead of the usual four.

This is a regular superspeed USB-A connector (albeit with both SSTX/SSRX contact pairs omited). Standard SS USB-A cable would work just fine here:

https://en.wikipedia.org/wiki/Usb3#Connectors

kees99on How a $2k 'Made in the USA' Phone Is Manufactured

"PCBA assembly" is up there with "IQ quotient" and "ROI on investment". No editor writes like that either.

kees99on DigitalOcean blocks SMTP ports 465 and 587 since last month

I guess GP meant that online shops, mechanics, government bodies and schools were meant to move along?

Not exactly clear where to, though. We don't have another messaging system with quite as wide reach (a.k.a. high value, in terms of Metcalfe's law) as email.

Texts(SMS), maybe? But those are not without their own problems - see "green text bubble stigma".

kees99on DigitalOcean blocks SMTP ports 465 and 587 since last month

DigitalOcean, or more precisely - some of their customers are the source of quite a few spam tsunamis, at least according to spamtrap data I'm collecting on my mail server. So from that perspective, a big "thank-you" goes out to DO for firewalling off outbound port-25 traffic by default.

That said - reading "Even if SMTP were available" and "recommend using SendGrid", it sounds like there is no opt-out from this. Even for customers who would want to self-host a mail server that never sends in bulk. Now that, is reprehensible, and adds yet another brick in the already tall wall that mail duopoly+ (gmail, outlook, and handful others) enjoy.

kees99on Build an 8-bit computer from scratch (2016)

> just plain wrong -- e.g. floating inputs or missing resistors

TTL logic gates have no problem with floating inputs. Those are interpreted as logic high. [1]

This is fairly self-evident from looking at a typical TTL gate schematics. [2]

Some "TTL-compatible" CMOS parts (including 65C02) have internal pull-ups on inputs, to match this quirk. [3]

Granted, it is a bad habit to develop, given that nearly all "modern" logic (i.e. of past 30+ years) is CMOS with no "TTL compatibility", and floating inputs are a big problem there.

[1] https://electronics.stackexchange.com/questions/683051/outpu...

[2] https://upload.wikimedia.org/wikipedia/commons/thumb/d/d4/TT...

[3] https://wilsonminesco.com/NMOS-CMOSdif/

kees99on Spammers are better at SPF, DKIM, and DMARC than everyone else

For a greylisting that sends 451 before DATA, that is indeed a known problem.

My server sends 451 after DATA, and keeps a copy of greylisted message, as marked-as-read entry in separate folder. Those are deleted after few hours, or moved out after a successful delivery retry.

kees99on Spammers are better at SPF, DKIM, and DMARC than everyone else

I'm using something very similar, except incoming messages from never-seen-before senders are greylisted instead:

https://en.wikipedia.org/wiki/Greylisting_(email)

95% of spammers never retry.

kees99on When you deleted /lib on Linux while still connected via SSH (2022)

You were lucky scp uses a binary that typically lives outside /bin - in /usr/lib/openssh/ or some such.

Many years ago, I've got to recover a remote server where /usr was nuked (and /bin, /sbin, and /lib were all symlinks into now-empty /usr). Ended up writing a one-liner perl to convert /bin/busybox-static from my local machine into a series of:

  echo -ne "\x7f\x45..." >>~/busybox-static

...and copy-pasting that, chunk-by-chunk, into a single surviving ssh/bash connection, and then used that busybox binary to pull in from a backup.

kees99on Netherlands Daft Visa for Americans

https://en.wikipedia.org/wiki/DAFT_(treaty)

kees99on Apple unveils new Mac Studio

Chrome has to run on chromebooks, quite a few of which are still-supported models with 4GB of non-upgradeable RAM.

kees99on Comparing Fuchsia components and Linux containers [video]

Shipping toybox instead of busybox is even more telling of that exact mindset.

kees99on Yes, Claude Code can decompile itself. Here's the source code

Decent optimizing compiler would necessarily loose a fair bit of source information - loop unrolling, function inlining, tail-call optimizations, etc...

There is no good way to reconstruct that, AI/ML or not.

kees99on Frontier AI systems have surpassed the self-replicating red line

Not quite "self-replicating AI". More of a quine. Still cool, though.

https://en.wikipedia.org/wiki/Quine_(computing)

kees99on ReCAPTCHA: 819M hours of wasted human time and billions in Google profits

A while ago, our office switched ISPs, and we got IP from a block that was previously registered in Spain.

Even though RIPE records were correct from day one (we're in the Netherlands), some databases somewhere took a full year to update. All that time, almost all ads were in Spanish.

kees99on The origins of 60-Hz as a power frequency (1997)

5400 is (was?) very common RPM for laptop HDDs.

kees99on Copilot stops working on code that contains hardcoded banned words from GitHub (2023)

> obvious PR implications

That's the right answer. And it's not like this is a potential risk that is only being theorized about. Microsoft already has a very hands-on experience with disasters of this exact nature:

https://en.wikipedia.org/wiki/Tay_(chatbot)