Checking In On The ISA Wars And Its Impact On CPU Architectures

An Instruction Set Architecture (ISA) defines the software interface through which for example a central processor unit (CPU) is controlled. Unlike early computer systems which didn’t define a standard ISA as such, over time the compatibility and portability benefits of having a standard ISA became obvious. But of course the best part about standards is that there are so many of them, and thus every CPU manufacturer came up with their own.

Throughout the 1980s and 1990s, the number of mainstream ISAs dropped sharply as the computer industry coalesced around a few major ones in each type of application. Intel’s x86 won out on desktop and smaller servers while ARM proclaimed victory in low-power and portable devices, and for Big Iron you always had IBM’s Power ISA. Since we last covered the ISA Wars in 2019, quite a lot of things have changed, including Apple shifting its desktop systems to ARM from x86 with Apple Silicon and finally MIPS experiencing an afterlife in  the form of LoongArch.

Meanwhile, six years after the aforementioned ISA Wars article in which newcomer RISC-V was covered, this ISA seems to have not made the splash some had expected. This raises questions about what we can expect from RISC-V and other ISAs in the future, as well as how relevant having different ISAs is when it comes to aspects like CPU performance and their microarchitecture.

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You Know Pi, But Do You Really Know E?

Pi Day is here! We bet that you know that famous constant to a few decimal points, and you could probably explain what it really means: the ratio of a circle’s circumference to its diameter. But what about the constant e? Sure, you might know it is a transcendental number around 2.72 or so. You probably know it is the base used for natural logarithms. But what does it mean?

The poor number probably needed a better agent. After all, pi is a fun name, easy to remember, with a distinctive Greek letter and lots of pun potential. On the other hand, e is just a letter. Sometimes it is known as Euler’s number, but Leonhard Euler was so prolific that there is also Euler’s constant and a set of Euler numbers, none of which are the same thing. Sometimes, you hear it called Napier’s constant, and it is known that Jacob Bernoulli discovered the number, too. So, even the history of this number is confusing.

But back to math, the number e is the base rate of growth for any continually growing process. That didn’t help? Well, consider that many things grow or decay through growth. For example, a bacteria culture might double every 72 hours. Or a radioactive sample might decay a certain amount per century. Continue reading “You Know Pi, But Do You Really Know E?”

Inexpensive Repairable Laptops, With Apple Style

Despite a general lack of real-world experience, many teenagers are overly confident in their opinions, often to the point of brashness and arrogance. In the late 90s and early 00s I was no different, firmly entrenched in a clichéd belief that Apple computers weren’t worth the silicon they were etched onto—even though I’d never actually used one. Eventually, thanks to a very good friend in college, a bit of Linux knowledge, and Apple’s switch to Intel processors, I finally abandoned this one irrational belief. Now, I maintain an array of Apple laptops for my own personal use that are not only surprisingly repairable and hacker-friendly but also serve as excellent, inexpensive Linux machines.

Of course, I will have ruffled a few feathers suggesting Apple laptops are repairable and inexpensive. This is certainly not true of their phones or their newer computers, but there was a time before 2016 when Apple built some impressively high quality, robust laptops that use standard parts, have removable batteries, and, thanks to Apple dropping support for these older machines in their latest operating systems, can also be found for sale for next to nothing. In a way that’s similar to buying a luxury car that’s only a few years old and letting someone else eat the bulk of the depreciation, a high quality laptop from this era is only one Linux install away from being a usable and relatively powerful machine at an excellent bargain. Continue reading “Inexpensive Repairable Laptops, With Apple Style”

Open Source Hardware, How Open Do You Want It To Be?

In our wider community we are all familiar with the idea of open source software. Many of us run it as our everyday tools, a lot of us release our work under an open source licence, and we have a pretty good idea of the merits of one such document over another. A piece of open source software has all of its code released under a permissive licence that explicitly allows it to be freely reproduced and modified, and though some people with longer beards take it a little too seriously at times and different flavours of open source work under slightly different rules, by and large we’re all happy with that.

When it comes to open hardware though, is it so clear cut?  I’ve had more than one rant from my friends over the years about pieces of hardware which claim to be open-source but aren’t really, that I think this bears some discussion.

Open Source Hardware As It Should Be Done

To explore this, we’ll need to consider a couple of open source hardware projects, and I’ll start close to home with one of my own. My Single 8 home movie cartridge is a 3D printable film cartridge for a defunct format, and I’ve put everything necessary to create one yourself in a GitHub repository under the CERN OHL. If you download the file and load it into OpenSCAD you can quickly create an STL file for your slicer, or fiddle with the code and make an entirely new object. Open source at its most efficient, and everyone’s happy. I’ve even generated STLs ready to go for each of the supported ISO values. Continue reading “Open Source Hardware, How Open Do You Want It To Be?”

FOSDEM 2025, A Hardware Hacker’s Haven

Have you been to FOSDEM? It’s a yearly two-day megaconference in Brussels, every first weekend of February. Thousands of software and hardware hackers from all across Europe come here each year, make friends, talk software and hardware alike, hold project-specific meetups to drink beer and talk shop, and just have a fun weekend surrounded by like-minded people.

In particular, FOSDEM has free admission – drop by for the weekend, no need to buy entry tickets, just sort out your accomodation, food, travel, and visit for a day or two. I’ve covered FOSDEM quite extensively in 2023, so if you want to know more about how it works, I invite you to check out that article – plenty of stories, cool facts about FOSDEM, showcases, and so on. This year, I’ve also been to FOSDEM, it’s been pretty great, and I’d like to tell you about cool things I’ve seen happen during FOSDEM 2025.

FOSDEM is often described as an open software conference, and you might’ve had been fooled by this if you simply have checked the Wikipedia page. However, let me assure you – there’s always plenty of hardware, large amounts of it! This year, I feel like hardware has taken the spotlight in particular – let me show you at least some of it, so that you know what kinds of cool stuff you can expect and plan for in 2026.

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Tech In Plain Sight: Shopping Cart Locks

The original locking wheel.

Shopping carts are surprisingly expensive. Prices range up to about $300 for a cart, which may seem like a lot, but they have to be pretty rugged and are made to work for decades. Plastic carts are cheaper, but not by much.

And carts have a way of vanishing. We’ve seen estimates that cart theft costs hundreds of millions of dollars worldwide annually. To stem the tide, stores sometimes pay a reward to people to round up carts off the street and return them to the store — it’s cheaper than buying a new one. That led [Elmer Isaacks] to patent a solution to this problem in 1968.

The [Isaacks] system used lots of magnets. A cart leaving the store had a brake that would be armed by running over a magnet. Customers were expected to follow a path surrounded by magnets to prevent the brake from engaging. If you left the track, a rod passing through the wheel locked it.

A third magnet would disarm the brake when you entered the store again. This is clever, but it has several problems. First, you have to insert magnets all over the place. Second, if someone knows how the system works, a simple magnet will hold the brake off no matter what. Continue reading “Tech In Plain Sight: Shopping Cart Locks”

What Game Should Replace Doom As The Meme Port Of Choice?

DOOM. The first-person shooter was an instant hit upon its mrelease at the end of 1993. It was soon ported off the PC platform to a number of consoles with varying success. Fast forward a few years, and it became a meme. People were porting Doom to everything from thermostats to car stereos and even inside Microsoft Word itself.

The problem is that porting Doom has kind of jumped the shark at this point. Just about every modern microcontroller or piece of consumer electronics these days has enough grunt to run a simple faux-3D game engine from 1993. It’s been done very much to death at this point. The time has come for a new meme port!

Good Game

Doom became a popular meme port for multiple reasons. For one, it’s just complex and resource-intensive enough to present a challenge, without being so demanding as to make ports impractical or impossible. It’s also been open-source for decades, and the engine has been hacked to death. It’s probably one of the best understood game engines out there at this point. On top of that, everybody plays Doom at some point, and it was one of the biggest games of the 90s. Put all that together, and you’ve got the perfect meme port.

However, you can always have too much of a good thing. Just as The Simpsons got old after season 10 and Wonderwall is the worst song you could play at a party, Doom ports have been overdone. But what other options are there? Continue reading “What Game Should Replace Doom As The Meme Port Of Choice?”