lcamtuf
@lcamtuf.coredump.cx
📤 3486
📥 243
📝 177
Substack:
http://lcamtuf.substack.com/archive
Homepage:
http://lcamtuf.coredump.cx
OK, after a year, I'm done with Bluesky. I might be using it wrong, but I get very little human interaction here and my feed consists 100% of outrage politics. I'm on Mastodon (
infosec.exchange/@lcamtuf
), Twitter, or can be reached at
[email protected]
. I also write at
lcamtuf.substack.com
.
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lcamtuf :verified: :verified: :verified: (@
[email protected]
)
480 Posts, 305 Following, 11.6K Followers ·
https://infosec.exchange/@lcamtuf
about 1 month ago
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about 2 months ago
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Cursed circuits #4: PLL frequency multiplier
lcamtuf.coredump.cx/blog/pll/
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Cursed circuits #4: PLL frequency multiplier
How do you turn 1 MHz into 100 MHz? With magic, of course.
https://lcamtuf.coredump.cx/blog/pll/
about 2 months ago
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I recently refreshed my article on analog-to-digital and digital-to-analog conversions. Did you know that there are many different ways to convert analog voltages to bits and bytes, and that some of the methods are quite... unhinged? Check it out:
lcamtuf.coredump.cx/blog/convers...
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DACs and ADCs, or there and back again
A look at how digital-to-analog and analog-to-digital converters work - from resistor ladders to delta-sigma modulation.
https://lcamtuf.coredump.cx/blog/conversions/
about 2 months ago
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Cursed circuits 3: true mathematics
lcamtuf.coredump.cx/blog/true/
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Cursed circuits #3: true mathematics
Op-amp arithmetics, explained in a more accessible way
https://lcamtuf.coredump.cx/blog/true/
about 2 months ago
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New mini display
2 months ago
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Cursed circuits #2: switched capacitor lowpass -
lcamtuf.coredump.cx/blog/switched/
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Cursed circuits #2: switched capacitor lowpass
Still using resistors? Get on with the times.
https://lcamtuf.coredump.cx/blog/switched/
2 months ago
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Cursed circuits: voltage halver
lcamtuf.coredump.cx/blog/halver/
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Cursed circuits: charge pump voltage halver
There's plenty of circuits that are hard to understand because they're complicated. And some that are hard to make sense of because they seem too simple.
https://lcamtuf.coredump.cx/blog/halver/
2 months ago
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It's hard to build an oscillator:
lcamtuf.coredump.cx/blog/oscilla...
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It's hard to build an oscillator
Especially if you want it to work.
https://lcamtuf.coredump.cx/blog/oscillator/
3 months ago
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Me: I want to have more friends Tech companies:
3 months ago
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When it comes to writing, LLMs have won -
lcamtuf.coredump.cx/blog/llm-win/
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When it comes to writing, LLMs have won
As a middling author, I find it fairly easy to sniff out LLM-generated articles.
https://lcamtuf.coredump.cx/blog/llm-win/
3 months ago
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What's the deal with Euler's identity?
lcamtuf.coredump.cx/blog/euler/?b
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What's the deal with Euler's identity?
Untangling a cursed formula from 1748.
http://lcamtuf.coredump.cx/blog/euler/?b
3 months ago
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Things you can do with diodes:
lcamtuf.coredump.cx/blog/diodes/?b3
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Things you can do with diodes
Paying homage to the component we usually don't think about.
https://lcamtuf.coredump.cx/blog/diodes/?b3
3 months ago
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You know, life used to be more fun in the 1930s
4 months ago
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Weekend projects: Chicken Squisher -
lcamtuf.coredump.cx/blog/squisher/
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Weekend projects: Chicken Squisher 3000
If it clucks like a duck...
https://lcamtuf.coredump.cx/blog/squisher/
4 months ago
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October is Cybersecurity Awareness Month! Please be aware of cybersecurity. If you encounter cybersecurity, DO NOT APPROACH IT. Back away slowly. Protect children and pets. Make noises to scare it away.
4 months ago
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Today I needed a bit of code, but instead of asking an LLM I tried writing it myself and wow, this could be a new paradigm
4 months ago
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OK, here it is - the latest in captcha technology:
lcamtuf.coredump.cx/captcha/
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One more step
https://lcamtuf.coredump.cx/captcha/
4 months ago
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Zombies:
lcamtuf.coredump.cx/blog/zombies/?n2
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Zombies
Interior of an abandoned, boarded-up convenience store.
https://lcamtuf.coredump.cx/blog/zombies/?n2
5 months ago
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How has mathematics gotten so abstract?
lcamtuf.coredump.cx/blog/abstract/?1
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How has mathematics gotten so abstract?
Georg Cantor's turtles, Giuseppe Peano as a software engineer, and other tales of from the kingdom of the infinite.
https://lcamtuf.coredump.cx/blog/abstract/?1
5 months ago
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My wife asked me some time ago to build an automated door opener / closer for the coop, and needless to say, our design firm takes this very seriously
5 months ago
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The joys of rural living
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5 months ago
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Boss: hey Bob, our users are asking for an API to determine if a video can be played in the browser. Bob: yeah, I get it, but this is really complica -- Boss: go on now, git! You'll figure it out. Bob: [muttering to himself]
5 months ago
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The latest
5 months ago
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Folks, we have the best π:
lcamtuf.substack.com/p/folks-we-h...
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Folks, we have the best π
In the past couple of months, I published a number of articles on recreational math.
https://lcamtuf.substack.com/p/folks-we-have-the-best
5 months ago
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Lord give me strength to stay on this platform
5 months ago
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Getting silly with C, part ~(~1<<1)
lcamtuf.coredump.cx/blog/c3/?n
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Getting silly with C, part ~(~1<<1)
In the two previous installments of our introductory series on the C programming language, we talked about types, variables, and control flow.
https://lcamtuf.coredump.cx/blog/c3/?n
5 months ago
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How many dimensions is this?
lcamtuf.coredump.cx/blog/dimensi...
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How many dimensions is this?
With the right incentives, you can convince a PhD to stack boxes in a warehouse.
https://lcamtuf.coredump.cx/blog/dimensions/
5 months ago
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My position on the "doomsday" risk of superhuman AGI is that if IQ offered you a decisive advantage, the world would be run by nerds. I think it's essentially a geek power fantasy. The returns on puzzle-solving skills rapidly diminish past some modest threshold.
6 months ago
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I'm sorry folks, the spec made it clear
6 months ago
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6 months ago
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An update on the chicken coop. Doors and windows by my wife (there's another window on the back, and a chicken door inside).
7 months ago
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Multitudes:
lcamtuf.substack.com/p/multitudes
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Multitudes
A warm, late-summer night in Bruges.
https://lcamtuf.substack.com/p/multitudes
7 months ago
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If you work in software, you know about the halting problem. But you *can* decide if a program halts in a finite number of steps! Except, when you do, it kinda summons the ghost of Kurt Gödel. An accessible essay on the limits of algorithmic knowledge:
lcamtuf.coredump.cx/blog/beavers...
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Gödel's beavers, or the limits of knowledge
Can you examine infinitely many integers in finite time? Are there numbers you're not allowed to know? Can a monkey beat a beaver in a fair fight?
http://lcamtuf.coredump.cx/blog/beavers/?q
7 months ago
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A slightly unhinged calculator fact: in the golden era of electronic calculators, some Japanese shopkeepers were reluctant to trust the newfangled device, so Sharp made a line of combination calculator / abacus devices. Here's a photo, next to some other stuff I own.
8 months ago
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An update on an update on the chicken coop
8 months ago
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I don't know where you folks get your non-orientable manifolds, but the experience of ordering from Cliff Stoll at
kleinbottle.com
is second to none
8 months ago
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What is infinity, and why it's not trivial to show that 0.9999... is equal to 1:
lcamtuf.substack.com/p/09999-1
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0.9999... ≊ 1
What is infinity, and why it's not trivial to show that 0.9999... is equal to 1.
https://lcamtuf.substack.com/p/09999-1
8 months ago
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The proof that π = 4
lcamtuf.coredump.cx/blog/pi/
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π = 4
Trolls do a pretty good job of getting people interested in math.
https://lcamtuf.coredump.cx/blog/pi/
8 months ago
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Self-referential abstractions, or a quick look at the wacky epistemology of analog circuitry.
lcamtuf.coredump.cx/blog/abstrac...
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Self-referential abstractions
A quick look at the wacky epistemology of analog circuitry.
https://lcamtuf.coredump.cx/blog/abstractions/?n
8 months ago
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I finally decided to bite the bullet
8 months ago
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An update on chickens
9 months ago
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A 20-minute intro to complex numbers (featuring cats):
lcamtuf.coredump.cx/blog/complex/
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A 20-minute intro to complex numbers
You might have heard of complex numbers before -- but why exactly did we choose i = √-1?
https://lcamtuf.coredump.cx/blog/complex/
9 months ago
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9 months ago
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Decibels are ridiculous:
lcamtuf.coredump.cx/blog/decibels/
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Decibels are ridiculous
Celebrating a rare dumpster fire in the kingdom of science
https://lcamtuf.coredump.cx/blog/decibels/
9 months ago
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There's this joke primality testing library that claims 95% accuracy in O(1) time:
github.com/mawerty/Is-P...
It does so by always returning false. The density of primes between 1 and n approaches 1/ln(n). For a 32-bit int, 4.6% of values are prime, so the code is right 95.4% of the time. 🡇
9 months ago
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Can you have complex numbers in 3D, and what the heck are quaternions?
lcamtuf.coredump.cx/blog/complex2/
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Complex numbers #2: a world in 3D
Why is there no equivalent of complex numbers for three dimensions? And what's the deal with quaternions?
https://lcamtuf.coredump.cx/blog/complex2/
9 months ago
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I'm old enough to remember when our #1 concern about the veracity of online information was that anyone could edit Wikipedia
9 months ago
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The Mathematics of Love:
lcamtuf.coredump.cx/blog/love/
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The Mathematics of Love
Interior of an upscale restaurant, night.
https://lcamtuf.coredump.cx/blog/love/
9 months ago
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