DOS Gaming PC Gets Necessary Updates

PC-104 is a standard computer form factor that most people outside of industrial settings probably haven’t seen before. It’s essentially an Intel 486 processor with lots of support for standards that have long since disappeared from most computers, but this makes it great for two things: controlling old industrial equipment and running classic DOS games on native hardware. For the latter, we turn once again to [The Rasteri] who is improving on his previous build with an even smaller DOS gaming rig, this time based on a platform even more diminutive than PC-104.

The key of a build like this is that it needs native support for the long-obsolete ISA bus to be able to interface with a SoundBlaster card, a gold standard for video games of the era. This smaller computer still has this functionality in a smaller package, but with some major improvements. First, it has a floating point unit so it can run games like Quake. It’s also much faster than the PC-104 system and uses less power. Finally, it fits in an even smaller case.

The build goes well beyond simply running software on a SoM computer. [The Rasteri] also custom built an interface board for this project, complete with all of the necessary ports and an ISA sound chip, all while keeping size down to a minimum. The new build also lets him give the build a better name than the old one (although he phrases this upgrade slightly differently), and will also let him expand some features in the future as well. Be sure to check out that first build if you’re new to this saga, too.

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Guide To Mastering OpenSCAD Costs Roughly The Same As OpenSCAD

OpenSCAD is a fantastic free tool for 3D modeling, but it’s far less intuitive to use for non-programmers than mouse-driven programs such as Tinkercad. Powerful as it may be, the learning curve is pretty steep. OpenSCAD’s own clickable cheat sheet and manual comes in handy all the time, but those are really more of a reference than anything else. Never fear, because [Jochen Kerdels] had quite the productive lockdown and wrote a free comprehensive guide to mastering OpenSCAD.

[Jochen]’s book opens with a nice introduction to OpenSCAD and it’s user environment and quickly moves into 10 useful projects of increasing complexity that start with simple stuff like wall anchors and shelf brackets and ends with recursive trees.

There are plenty of printing tips along the way to help realize these projects with minimum frustration, and the book wraps up by covering extra functions not expressly used in the projects.

Of course, you could always support [Jochen]’s Herculean effort by buying the print edition and forcing yourself to type everything in instead of copy/pasting, or give it to someone to introduce them to all the program has to offer.

Need help mastering OpenSCAD workflow? We’ve got that. Just want to make some boxes or airfoils? We have those in stock, too.

Main and thumbnail images via [Devlin Thyne]

Pedaling Away Under The Cover Of Your Desk

[Wayne Venables], like many of us, found himself sitting more than usual the past few months.  Armed with a Bluetooth-enabled under desk exercise bike, he quickly found the app to be rather sub-optimal and set about reverse-engineering the protocol of his bike.

Custom GUI for the exercise bike

The first step was to use some apps on his Android phone to reveal the profiles on the bike, which showed his particular machine used a Nordic Bluetooth UART. This meant the only work would be decoding the stream of bytes coming off the wireless serial port. Using Wireshark and Bluetooth logs on his phone, [Wayne] was able to correspond the various commands to points in the video. There were still a few bytes that he wasn’t able to identify, but [Wayne] had enough to whip up a quick .NET app that can start a workout and log it all to a database. The code for his app is on his GitHub.

While [Wayne] doesn’t specifically name the bike he uses in this project, we tracked down the image he shows on his writeup to the Exerpeutic 900e. It appears to be discontinued but the reverse engineering approach should be usable on a range of Bluetooth-connected machines. This isn’t the first bike we’ve seen liberated by reverse engineering here at Hackaday. And we have a feeling it won’t be the last.

Kitchen Bump Bar Plays Doom Between Orders

For as much as we love reverse engineering projects, we have to admit that we almost passed up on this “kitchen bump bar” hack. Having never had the privilege of working in the food-service industry — well, there was that time working at Chuck E. Cheese’s, but that only lasted for one shift — we were unaware of what a bump bar is, and the whys and hows of hacking one to the point where it can play Doom.

We’re glad we stuck with it, though, because [Kiwa]’s hack is pretty cool, and we got to learn a little about the technology of the modern commercial kitchen. Most fast food and family casual restaurants have what’s known as a “kitchen display system”, which relays orders from the wait staff to the kitchen. You’ve probably seen parts of the KDS, like the touch screens used by the wait staff to enter orders, or the screens dangling in the kitchen that display the pending orders. A bump bar is a small terminal used by the kitchen crew to review orders and move them around in the queue, or “bump” them, as needs dictate.

The bump bar [Kiwa] dug into appears to be a model from the early 2000s and very sturdily built, as anything used in a kitchen would need to be. Hooked up to a monitor and a keyboard, [Kiwa] discovered that it booted right into an OS with all the familiar trappings of DOS. After a detour for a teardown and dumping the flash contents, [Kiwa] was able to boot it up and run Doom, albeit somewhat slowly. It also looks like he’s got a couple of different Windows versions running, and even played some Solitaire.

It’s always fun to see what will run Doom — an NES, an oscilloscope, a thermostat, or even a bag of potatoes.

Thanks to [Fritnando] for the tip.

A HALO Of LEDs For Every Ear

Few things get a Hackaday staffer excited like bunches of tiny LEDs. The smaller and denser the better, any form will do as long as we can get a macro shot or a video of a buttery smooth animation. This time we turn to [Sawaiz Syed] and [Open Kolibri] to deliver the brightly lit goods with the minuscule HALO 90 reactive LED earrings.

The HALO 90’s are designed to work as earrings, though we suspect they’d make equally great brooches, hair accessories, or desk objects. To fit this purpose each one is a minuscule 24 mm in diameter and weighs a featherweight 5.2 grams with the CR2032 battery (2.1 g for the PCBA alone). Functionally their current software includes three animation modes, each selectable via a button on device; audio reactive, halo (fully lit), and sparkle. Check out the documentation for details on expected battery life in each mode, but suffice to say that no matter what these earrings will make it through a few nights out.

In terms of hardware, the HALO 90’s are as straightforward as you’d expect. Each device is driven by an STM8 at its maximum 16MHz which is more than fast enough to keep the 90 charliplexed 0402 LEDs humming along at a 1kHz update rate, even with realtime audio processing. In fact the BOM here is refreshingly simple with just 8 components; the LEDs, microcontroller and microphone, battery holder and passives, and the button. [Sawaiz] even designed an exceptionally slick case to go with each pair of earrings, which holds two HALO 90’s with two CR2032’s and includes a magnetic closure for the most satisfying lid action possible.

As with some of his other work, [Sawaiz] has produced a wealth of exceptional documentation to go with the HALO 90’s. They’re available straight from him fully assembled, but with documentation this good the path to a home build should be well lit and accessible. He’s even chosen parts with an eye towards long availability, low cost, and ease of sourcing so no matter when you decide to get started it should be a snap.

It was difficult to choose just a few images from [Sawaiz]’s mesmerizing collection, so if you need more feast your eyes on the expanded set after the break.

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Junkbox Confidential

Thomas Edison famously quipped “To invent, you need a good imagination and a pile of junk.” Amen, brother. My personal junk pile (ahem, collection of pre-owned electromechanical curiosities) is certainly a source of spare parts, but also a source of surprise and wonder. Sometimes the junk itself spurs the imagination, but sometimes junk is just junk.

There are pieces of used gear that I bought for some particular plan, maybe a decade ago?, and totally forgot. While it’s fun to rediscover them — I bought six used super-soaker pump assemblies, and summer is just around the corner — the sad truth is often that the forgotten pieces were forgotten for a reason. Whatever kooky idea I had at the time has faded, and the parts are all that’s left.

But among these miserable creatures, there are some absolute gems. Parts that continually call out to be used. Bits that would fire even Thomas Edison’s imagination. Unforgetable junk.
Mostly, it’s their physicality that calls out to me. I have a stack of old 5″ hard drive platters, gutted, and converted into essentially a rotary encoder. For years, I used it as a USB scroll wheel on my desk, but most recently it has made reappearances in other goofy projects — a music box for my son that played notes in a row depending on how fast you spun it, and most recently a jog wheel for a one-meter linear motion project that hasn’t really found its full expression yet, but might become a camera slider. Anyway, when I needed a nice physical rotary encoder knob, the hard drive was just sitting there waiting to be used. Continue reading “Junkbox Confidential”

E.T. Video Game Gets Re-Imagined In 10 Lines Of BASIC

Most people would recognize E.T. The Extra-Terrestrial for the Atari 2600 by its reputation as one of the worst video games of all time. We’ll have more to say about that in a moment, but E.T. was nevertheless chosen as the inspiration behind [Martin Fitzpatrick]’s re-imagining of the game in ten lines of BASIC code for a contest that encourages and celebrates games written in ten lines of BASIC, or less.

Ten lines of BASIC is a big limitation, even when getting clever by stacking multiple statements into a single line, so [Martin]’s game has a much narrower scope than the original Atari 2600 version. Still, the core elements are present: E.T. must find and gather all the parts of the phone in order to contact his ship, after which he must meet the ship in time to escape. All the while, FBI agents attempt to interfere. The game was written in SAM BASIC, used by the SAM Coup√©, a British Z80-based home computer from the late 80s with an emulator available for download.

Now, for lovers of “um, actually” topics, do we have a treat for you! Let’s take this opportunity to review a few things about E.T. The Extra-Terrestrial. That it was a commercial flop is no doubt, but the game itself is often badly misunderstood. Way back in 2013 we covered an extraordinary effort to patch improvements into the binary for the 2600 game, and in the process there’s a compelling case made that the game was in many ways far ahead of its time, and actually quite significant in terms of game design. You can jump right in on an analysis of the hate the game receives, and while reading that it’s helpful to keep in mind that In 1982, many of its peers were games like Space Invaders, with self-evident gameplay that simply looped endlessly.