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The purpose of this article is to explain how to make a CPU out of rocks and sand as fast as possible without using too many words. As the world of proprietary hardware and software crushes in around us, we risk losing the ability to make things for ourselves as individuals. It is for this reason that I felt compelled…
This article will discuss the setup steps that are required for recording videos at high frame rates on cheap Raspberry Pi cameras. Frame rates up to 660FPS on the V1 camera and up to 1007 on the V2 camera can be achieved. Filming at these extremely high frame rates on a Raspberry Pi is much more challenging and…
In this article, I will attempt to convince you that Expect is an extremely underappreciated tool for automating terminal applications in Unix.
If you don't you're not alone. Right now, as I'm typing this, 4 of the top 4 Google results for "find command linux" contain at least one example of the pattern illustrated by the command above.
Updated Oct 27, 2016: Fixed sample code comments in coroutine example as per suggestion , edited text to note D's similar behaviour .
Many of my students have been asking questions lately about how to do technical interviews, so I've decided to write about my interviewing experiences. I will start by giving a number of anecdotes because they're interesting to everyone, but the later parts of this post are mainly targeted at prospective students who…
The purpose of this article is to show you step-by-step examples of how to use the Fourier transform algorithm to multiply two numbers. The primary advantage of using fourier transforms to multiply numbers is that you can use the asymptotically much faster 'Fast Fourier Transform algorithm', to achieve better…
I just finished updating my C compiler and minimal CPU specification to include virtual memory. The process of adding virtual memory support to a CPU, a kernel, and a compiler toolchain has made me realize that there is a lack of good explanations for how all of these parts fit together. I also realized that a…
This article will provide the reader with a brief overview for a number of different Linux commands. A special emphasis will be placed on explaining how each command can be used in the context of performing data science tasks. The goal will be to convince the reader that each of these commands can be extremely useful…
Over the last 18 months, I've taken the time to create 108 short YouTube videos that summarize all of the commands that are found in the Coreutils Package . These videos focus mostly on Coreutils v8.3, but also included are a few commands from v9.0 as well. For each of the blog posts, I've adapted and modified the…
In a stuffed apartment filled with hydrofluoric acid, oscilloscopes and a transistor curve tracer, Jeri Ellsworth carefully places a hand-cut silicon wafer into a 1000 degree furnace. The ambient noise of police sirens can be heard in the background: "Ugh, the police are coming... So the instructions for the…
This article is about how to use the 'tail' command. Here is an overview of how you can use the 'head' and 'tail' commands to output different parts of a file:
Last Updated Dec 12, 2019: Fixed an off by one error (awk uses 1-based arrays!).
I recently came home to visit with family, but right now as I write this, it's 1:00am and I'm running memtest86+ by myself in the basement.
If you ask a software developer the question 'What are some example uses of semiconductors?', they'll probably mention 'silicon chips', like the ones found in processors or graphics cards. Indeed, this is probably the answer that I would have given just a couple years ago, but I have since become enlightened as to the…
An interface can be thought of as a contract between the system and the environment. In a computer program, the 'system' is the function or module in question, and the 'environment' is the rest of the project. The interface formally describes what can pass between the system and the environment. An 'implementation'…
This article is dedicated to discussing why it's so hard to detect the 'key up' or 'key release' event in a Linux terminal environment without relying on X server. Several techniques and code examples will be shown that are capable of detecting the keyup event on Linux (with and without an X server), but all…
This article will focus on discussing why the ancient text editor 'ed' works the way it does.
Which is the first answer to the first question if you search for 'sort a list' on Stack Overflow (which was answered by Devin Jeanpierre ).
In my attempts to learn the C programming language well enough to write my own C compiler , I've encountered some very interesting examples of C syntax that you generally don't see every day. All of these examples you'll see here will compile without warnings or errors even with very strict compiler flags in gcc and…
Dec 12, 2019 Update: This piece of software is no longer available as I have turned it off due to lack of interest. The article below used to contain a number of links which I have removed. The content below remains only for archival purposes.
Updated 2018-01-21: Added clarification related to assertion about lack of context free nature of the C preprocessor.