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Get eyes in the sky with your Raspberry Pi
Learn how to use your Raspberry Pi and a cheap USB TV tuner stick to start tracking flights overhead - up to 250 miles away from your location.
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The latest blog posts to take off on Hacker News. 264 posts.
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OpenBSD and the modern laptop
Did you think that OpenBSD is suitable only for firewalls and high-security servers? Think again. Here are my steps to transform a modern m...
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24-core CPU and I can’t move my mouse
This story begins, as they so often do, when I noticed that my machine was behaving poorly. My Windows 10 work machine has 24 cores (48 hyper-threads) and they were 50% idle. It has 64 GB of RAM an…
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GPU Performance for Game Artists
Performance is everybody’s responsibility, no matter what your role. When it comes to the GPU, 3D programmers have a lot of control over performance; we can optimize shaders, trade image quality for performance, use smarter rendering techniques… we have plenty of tricks up our sleeves. But there’s one thing we don’t…
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Analog Computers
Analog computers, predominant in high-performance computing until the 1970s, were forgotten when digital computers took over. We need to change that.
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Intel's Management Engine
Recent CPUs from Intel requires a binary called the “Management Engine” (Intel ME, or ME for short). This binary is one of three parts required if a business elects to use Intel’s Active Management Technology (AMT), which Purism avoids. Purism laptops can function with a neutralized and disabled ME, as we have tested…
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Pruning spaces from strings quickly on ARM processors
Suppose that I give you a relatively long string and you want to remove all spaces from it. In ASCII, we can define spaces as the space character (' '), and the line ending characters ('\r' and '\n'). I am mostly interested in algorithmic and performance issues, so we can simplify the problem by removing all ……
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I found a bug in Intel Skylake processors
Instructors of “Introduction to programming” courses know that students are willing to blame the failures of their programs on anything. Sorting routine discards half of the data? “That might be a Windows virus!” Binary search always fails? “The Java compiler is acting funny today!” More experienced programmers know…
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Bitcoin mining on a vintage Xerox Alto: very slow at 1.5 hashes/second
I've been restoring a Xerox Alto minicomputer from the 1970s and figured it would be interesting to see if it could mine bitcoins. I coded u...
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Sorting 2 Tons of Lego, Many Questions, Results
The machine is now capable of running un-attended for hours on end, which is a huge milestone. No more jamming or other nastiness that causes me to interrupt a run. Many little things contributed to this, I’ve looked at all the mechanics and figured out all the little things that went wrong one by one and have come up…
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Improvements to the Xerox Alto Mandelbrot drop runtime from 1 hour to 9 minutes
Last week I wrote a Mandelbrot set program for the Xerox Alto, which took an hour to generate the fractal. The point of this project was to...
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Masahiro Kikuno, Japanese Independent Watchmaker
A Japanese approach to watchmaking, executed by hand.
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One-Hour Mandelbrot: Creating a Fractal on the Vintage Xerox Alto
I wrote a short program to generate the Mandelbrot set on the Xerox Alto, a groundbreaking minicomputer from the 1970s. The program, in...
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Intro to SDR and RF Signal Analysis
A beginner's introduction to Software Defined Radio (SDR) and RF signal analysis, covering theory, tools, and visual signal characteristics.
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Is the x86 Architecture Sustainable?
Robert O'Callahan. Christian. Kiwi. Software guy. All content human-authored unless otherwise noted.
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Another Case of Obscure CPU Nondeterminism
Robert O'Callahan. Christian. Kiwi. Software guy. All content human-authored unless otherwise noted.
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Modifying Microsoft Flight Simulator 4 to run on three immersive monitors
How I modified DOSBox and the original Microsoft Flight Simulator 4 from 1989 to run on my immersive multi-display flight simulator set up.
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Is the keyboard faster than the mouse?
Which is faster, keyboard or mouse? A large number of programmers believe that the keyboard is faster for all (programming-related) tasks. However, there are a few widely cited webpages on AskTog which claim that Apple studies show that using the mouse is faster than using the keyboard for everything and that people…
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The Age of Nvidia
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