Author: Al Williams

4295 Articles

Slide Rule By Helix

June 4, 2025 by No comments

It is no secret that we like slide rules around the Hackaday bunker, and among our favorites are the cylindrical slide rules. [Chris Staecker] likes them, too, and recently even 3D printed a version. But spurred by comments on his video, he decided to try something that might be unique: a helical slide rule. You can see how it works in the video below.

With a conventional slide rule, the scale is rotated around a cylinder so that it is the same length as a much longer linear scale. However, this new slide rule bends the entire rule around a cylinder and allows the slide to move, just like a conventional slide rule. If you have a 3D printer, you can make your own.

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The 1972 INTERCAL Compiler Revealed

June 2, 2025 by 19 Comments

Have you ever heard of INTERCAL? If you haven’t, don’t feel bad. This relatively obscure language dates back to 1972 with the goal of being difficult to read and write. It is the intellectual parent of systems like brainf**k and other bad languages. Now, you can read the INTERCAL-72 source code thanks to a found printout. It will help if you can read SPITBOL, another obscure language that is a compiled version of SNOBOL (which is like an old-fashioned non-Unix awk program).

How strange it INTERCAL? Well, one of the statements is PLEASE. If you don’t use it enough, you’ll offend the interpreter, who will then ignore your program. But if you use it too much, then you are a suck up and, therefore, your program will be ignored again. If you think GOTO is a bad idea, you’ll just hate COME FROM, although that was from a later version of INTERCAL.

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A Brief History Of Fuel Cells

May 22, 2025 by 13 Comments

If we asked you to think of a device that converts a chemical reaction into electricity, you’d probably say we were thinking of a battery. That’s true, but there is another device that does this that is both very similar and very different from a battery: the fuel cell.

In a very simple way, you can think of a fuel cell as a battery that consumes the chemicals it uses and allows you to replace those chemicals so that, as long as you have fuel, you can have electricity. However, the truth is a little more complicated than that. Batteries are energy storage devices. They run out when the energy stored in the chemicals runs out. In fact, many batteries can take electricity and reverse the chemical reaction, in effect recharging them. Fuel cells react chemicals to produce electricity. No fuel, no electricity.

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The Make-roscope

May 20, 2025 by 10 Comments

Normal people binge-scroll social media. Hackaday writers tend to pore through online tech news and shopping sites incessantly. The problem with the shopping sites is that you wind up buying things, and then you have even more projects you don’t have time to do. That’s how I found the MAKE-roscope, an accessory aimed at kids that turns a cell phone into a microscope. While it was clearly trying to appeal to kids, I’ve had some kids’ microscopes that were actually useful, and for $20, I decided to see what it was about. If nothing else, the name made it appealing.

My goal was to see if it would be worth having for the kinds of things we do. Turns out, I should have read more closely. It isn’t really going to help you with your next PCB or to read that tiny print on an SMD part. But it is interesting, and — depending on your interests — you might enjoy having one. The material claims the scope can magnify from 125x to 400x.

What Is It?

The whole thing is in an unassuming Altoids-like tin. Inside the box are mostly accessories you may or may not need, like a lens cloth, a keychain, plastic pipettes, and the like. There are only three really interesting things: A strip of silicone with a glass ball in it, and a slide container with five glass slides, three of which have something already on them. There’s also a spare glass ball (the lens).

What I didn’t find in my box were cover slips, any way to prepare specimens, and — perhaps most importantly — clear instructions. There are some tiny instructions on the back of the tin and on the lens cloth paper. There is also a QR code, but to really get going, I had to watch a video (embedded below).

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Not A Sewing Machine: A Multimedia Briefcase

May 15, 2025 by 11 Comments

When you think of Singer, you usually think of sewing machines, although if you are a history buff, you might remember they diversified into calculators, flight simulation, and a few other odd businesses for a while. [Techmoan] has an unusual device from Singer that is decidedly not a sewing machine. It is a 1970s-era multimedia briefcase called the Audio Study Mate. This odd beast, as you can see in the video below, was a cassette player that also included a 35mm filmstrip viewer. Multimedia 1970s-style!

The film strip viewer is a bright light and a glass screen with some optics. You have to focus the image, and then a button moves the film one frame. However, that’s for manual mode. However, the tape could encode a signal to automatically advance the frame. That didn’t work right away.

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Remembering More Memory: XMS And A Real Hack

May 15, 2025 by 28 Comments

Last time we talked about how the original PC has a limit of 640 kB for your programs and 1 MB in total. But of course those restrictions chafed. People demanded more memory, and there were workarounds to provide it.

However, the workarounds were made to primarily work with the old 8088 CPU. Expanded memory (EMS) swapped pages of memory into page frames that lived above the 640 kB line (but below 1 MB). The system would work with newer CPUs, but those newer CPUs could already address more memory. That led to new standards, workarounds, and even a classic hack.

XMS

If you had an 80286 or above, you might be better off using extended memory (XMS). This took advantage of the fact that the CPU could address more memory. You didn’t need a special board to load 4MB of RAM into an 80286-based PC. You just couldn’t get to with MSDOS. In particular, the memory above 1 MB was — in theory — inaccessible to real-mode programs like MSDOS.

Well, that’s not strictly true in two cases. One, you’ll see in a minute. The other case is because of the overlapping memory segments on an 8088, or in real mode on later processors. Address FFFF:000F was the top of the 1 MB range.

PCs with more than 20 bits of address space ran into problems since some programs “knew” that memory access above that would wrap around. That is FFFF:0010, on an 8088, is the same as 0000:0000. They would block A20, the 21st address bit, by default. However, you could turn that block off in software, although exactly how that worked varied by the type of motherboard — yet another complication.

XMS allowed MSDOS programs to allocate and free blocks of memory that were above the 1 MB line and map them into that special area above FFFF:0010, the so-called high memory area (HMA). Continue reading “Remembering More Memory: XMS And A Real Hack” →

Welcome Your New AI (LEGO) Overlord

May 15, 2025 by 13 Comments

You’d think a paper from a science team from Carnegie Mellon would be short on fun. But the team behind LegoGPT would prove you wrong. The system allows you to enter prompt text and produce physically stable LEGO models. They’ve done more than just a paper. You can find a GitHub repo and a running demo, too.

The authors note that the automated generation of 3D shapes has been done. However, incorporating real physics constraints and planning the resulting shape in LEGO-sized chunks is the real topic of interest. The actual project is a set of training data that can transform text to shapes. The real work is done using one of the LLaMA models. The training involved converting Lego designs into tokens, just like a chatbot converts words into tokens.

There are a lot of parts involved in the creation of the designs. They convert meshes to LEGO in one step using 1×1, 1×2, 1×4, 1×6, 1×8, 2×2, 2×4, and 2×6 bricks. Then they evaluate the stability of the design. Finally, they render an image and ask GPT-4o to produce captions to go with the image.

The most interesting example is when they feed robot arms the designs and let them make the resulting design. From text to LEGO with no human intervention! Sounds like something from a bad movie.

We wonder if they added the more advanced LEGO sets, if we could ask for our own Turing machine?