Author: Al Williams

4468 Articles

Hobnobbing With The Knob

February 15, 2023 by 23 Comments

The scroll wheel might be the best thing that happened to the computer mouse since, well, the computer mouse. But sometimes you want something a little more tangible. For example, with a software-defined radio setup, it doesn’t feel right to scroll your mouse to change frequencies. That’s where [Wagiminator]’ USB knob would come in handy. Marrying a 3D printed case, some addressable LEDs, a rotary encoder, and a CH552E microcontroller, the knob appears to the host operating system as a normal USB keyboard. That means most programs can use it without any special drivers or software.

There’s honestly not much to the hardware. A custom PCB holds two WS2812’s, the tiny CPU, the encoder, and the USB plug. There are a few random discrete components, too, but not many. Everything you need is on the project page. The PCB layout, the software, the schematics, and the 3D print files. The code that does the main work is extremely simple. The USB code is a bit more complex (look in the include directory) but honestly, it isn’t as bad as most USB examples we’ve seen.

This project is ripe for hacking. The software is simple enough to modify easily. The 3D printed case wouldn’t be hard to spruce up or print in different colors. Following the example, this would make a reasonable core for a custom keyboard peripheral that used exotic keys instead of a rotary encoder.

Knobs can be simple or complex. If you want our take on the odd volume control, we used sonar.

Sol-20 Integrated Computer Teardown

February 14, 2023 by 19 Comments

[Action Retro] came into an antique Sol-20 computer and argues that it was the first totally integrated computer aimed at consumers that didn’t require you to buy or build some kind of terminal. These are fairly rare, so we appreciated the peek inside that you can see in the video below.

Sure, the Sol-20 wasn’t the very first computer out there in the market. It was, however, one of the first ones that didn’t need anything more exotic than a monitor to have a functional system (and the monitor was included). There were alternatives such as a Xerox Alto or a Wang 2200, but those had price tags that didn’t land them in your home. Even Apple, which would become famous for a turnkey system, was only producing the Apple I at that time. As the video points out, it was complete as long as you could build your own power supply and knew how to interface a keyboard — keeping in mind that keyboards were all wildly different in those days.

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Too Cool For 8-bit Retro? Try 1-bit Gaming

February 14, 2023 by 5 Comments

While the world has been racing for higher and higher bit counts for CPUs, there are always those that buck the trend. Consider the venerable Motorola MC14500B, a 1-bit CPU, no kidding. [Usagi Electric] built up a computer based on one of these chips using a breadboard but has since pulled it apart to use the breadboard for other things. So this time, he’s made a permanent version on a PCB and created a simple game to show it off. You can see the result in the video below.

Well, the chip had one bit in the datapath. It did not have any memory, but it did have a way to feed it 4-bit instructions, and, as you might guess, there were 16 possibilities for instructions. The chip was meant to replace industrial controllers where even a PLC might be overkill, and apparently, it did see some use in the real world.

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Citizen Science Finds Prehistoric Burial Mounds

February 14, 2023 by 13 Comments

What do you do when you have a lot of LiDAR data and not enough budget to slog through it? That’s the problem the Heritage Quest project was faced with — they had 600,000 LiDAR maps in the Netherlands and wanted to find burial mounds using the data. By harnessing 6,500 citizen scientists, they were able to analyze the data and locate over 1,000 prehistoric burial mounds, including many that were previously unknown, along with cart tracks, kilns, and other items of archaeological interest.

The project used Zooniverse, a site we’ve mentioned before, to help train volunteers to analyze data. The project had at least 15 volunteers examining each map. The sites date between 2,800 and 500 BC. Archaeologists spent the summer of 2021 verifying many of these digital finds. They took samples from 300 sites and determined that 80 of them were previously unknown. They estimate that the total number of sites found by the volunteers could be as high as 1,250.

This is a great example of how modern technology is changing many fields and the power of citizen science, both topics we always want to hear more about. We’ve seen NASA tapping citizen scientists, and we’ve even seen high school students building research buoys. So if you’ve ever wanted to participate in advancing the world’s scientific knowledge, there’s never been a better time to do it.

3D Printing Support Gets Down To Tacks

February 10, 2023 by 9 Comments

If you use supports for FDM 3D printing, you might find that some designs are more amenable than others to automatically-generated supports. [Slant 3D] , for example, shows a cool-looking eagle with a downward-curved beak that comes to a point. Using traditional supports would allow the print to succeed, but didn’t allow the beak to form correctly. To combat this, he uses something called a “thumbtack” in the design. There are several flavors, as you can see in the video below, and it widens out the small part yet has a tiny contact with the actual part so you can easily remove it.

One of the thumbtacks looks more like a Hersey’s kiss to us. It makes sense. The point can touch the part to support and the fat base gives a nice target for the automatic support feature in your slicer to grab. There’s also a spherical base so you can rotate to odd angles. The final thumbtack looks like an alien spacecraft and provides multiple contact points.

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Modernizing C Arrays For Greater Memory Safety

February 10, 2023 by 75 Comments

Lately, there has been a push for people to stop using programming languages that don’t promote memory safety. But as we still haven’t seen the death of some languages that were born in the early 1960s, we don’t think there will be much success in replacing the tremendous amount of software that uses said “unsafe” languages.

That doesn’t mean it’s a hopeless cause, though. [Kees Cook] recently posted how modern C99 compilers offer features to help create safer arrays, and he outlines how you can take advantage of these features. Turns out, it is generally easy to do, and if you get errors, they probably point out unexpected behavior in your original code, so that’s a plus.

We don’t think there’s anything wrong with C and C++ if you use them as you should. Electrical outlets are useful until you stick a fork in one. So don’t stick a fork in one. We really liked the recent headline we saw from [Sarah Butcher]: “If you can’t write safe C++ code, it’s because you can’t write C++.” [Cook’s] post makes a similar argument.  C has advanced quite a bit and the fact that 30-year-old code doesn’t use these new features isn’t a good excuse to give up on C.

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Understanding AI Chat Bots With Stanford Online

February 8, 2023 by 8 Comments

The news is full of speculation about chatbots like GPT-3, and even if you don’t care, you are probably the kind of person that people will ask about it. The problem is, the popular press has no idea what’s going on with these things. They aren’t sentient or alive, despite some claims to the contrary. So where do you go to learn what’s really going on? How about Stanford? Professor [Christopher Potts] knows a lot about how these things work and he shares some of it in a recent video you can watch below.

One of the interesting things is that he shows some questions that one chatbot will answer reasonably and another one will not. As a demo or a gimmick, that’s not a problem. But if you are using it as, say, your search engine, getting the wrong answer won’t amuse you. Sure, you can do a conventional search and find wrong things, but it will be embedded in a lot of context that might help you decide it is wrong and, hopefully, some other things that are not wrong. You have to decide.
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