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Showing posts from March, 2024

3D Printing Computer Space

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The first computer game available as a commercial arcade cabinet is unsurprisingly, a rare sight here in 2024. Nolan Bushnel and Ted Dabney’s 1971 Computer Space was a flowing fiberglass cabinet containing a version of the minicomputer game Spacewar! running on dedicated game hardware. The pair would of course go on to found the wildly successful Atari, leaving their first outing with its meager 1500 units almost a footnote in their history. Unsurprisingly with so relatively few produced, few made it out of the United States, so in the UK there are none to be found. [Arcade Archive] report on a fresh build of a Computer Space cabinet , this time not in fiberglass but via 3D printed plastic. The build itself is the work of [Richard Horne], and in the video he takes us through the design process before printing the parts and then sticking them all together to make the cabinet. Without a real machine to scan or measure he’s working from photographs of real machines, working out dime...

Exploit the Stressed-out Package Maintainer, Exploit the Software Package

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A recent security vulnerability — a potential ssh backdoor via the liblzma library in the xz package — is having a lot of analysis done on how the vulnerability was introduced, and [Rob Mensching] felt that it was important to highlight what he saw as step number zero of the whole process: exploit the fact that a stressed package maintainer has burned out . Apply pressure from multiple sources while the attacker is the only one stepping forward to help, then inherit the trust built up by the original maintainer. Sadly, [Rob] sees in these interactions a microcosm of what happens far too frequently in open source. Maintaining open source projects can be a high stress activity. The pressure and expectations to continually provide timely interaction, support, and updates can easily end up being unhealthy. As [Rob] points out (and other developers have observed in different ways ), this kind of behavior just seems more or less normal for some projects. The xz/liblzma vulnerability itsel...

Hackaday Links: March 31, 2024

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Battlelines are being drawn in Canada over the lowly Flipper Zero, a device seen by some as an existential threat to motor vehicle owners across the Great White North. The story started a month or so ago , when someone in the government floated the idea of banning devices that could be “used to steal vehicles by copying the wireless signals for remote keyless entry.” The Flipper Zero was singled out as an example of such a nefarious device, even though relatively few vehicles on the road today can be boosted using the simple replay attack that a Flipper is capable of, and the ones that are vulnerable to this attack aren’t all that desirable — apologies to the 1993 Camry , of course. With that threat hanging in the air, the folks over at Flipper Devices started a Change.org petition to educate people about the misperceptions surrounding the Flipper Zero’s capabilities , and to urge the Canadian government to reconsider their position on devices intended to explore the RF spectrum. Tha...

Give Your Pi Pico Captouch Inputs For All Your Music Needs

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Unlike many modern microcontrollers, RP2040 doesn’t come with a native capacitive touch peripheral. This doesn’t mean you can’t do it – the usual software-driven way works wonderfully, and only requires an external pullup resistor! In case you wanted a demonstration or you have a capacitive touch project in mind, this lighthearted video by [Jeremy Cook] is a must watch, and he’s got a healthy amount of resources for you in store, too! In this video, [Jeremy] presents you with a KiCad schematic and an PCB design you can use to quickly add whole 23 capacitive touch sensing inputs to a Pi Pico! The board is flexible mechanically, easy to assemble as [Jeremy] demonstrates, and all the pins involved can still be used as regular GPIOs if you’d like. Plus, it’s fully open-source, can easily be assembled on your own, and available on Tindie too! Of course, such a board doesn’t get created for no reason – [Jeremy] has a healthy amount of musical creations and nifty ideas to show off. We qui...

Playing Chess Against Your Printer, with PostScript

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Can you play chess against your printer? The answer will soon be yes, and it’s thanks to [Nicolas Seriot]’s PSChess . It’s a chess engine implemented in PostScript, of all things. It’s entirely working except for one last hurdle, but more on that in a moment. What’s it like to play PSChess? Currently, one uses a PostScript interpreter (such as GhostScript) to run it, much like one would use the Python interpreter to run Python code. The user inputs moves by typing in commands like d2d4 (representing a piece’s source coordinate and a destination coordinate on the 2D board). Then the program makes a move, and outputs an updated board state to both the console and a PDF document. Then it’s the user’s turn again, and so on until somebody loses. The chess parts are all working, but there’s one last feature in progress. The final step of the project is to enable PSChess to be run directly on a printer instead of using GhostScript as the interpreter. Intrigued? You can find the code at th...

Using Electroadhesion To Reversibly Adhere Metals and Graphite to Hydrogels and Tissues

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The usual way to get biological tissues and materials like gels and metals to stick together is using sutures, adhesives or both. Although this generally works, it’s far from ideal, with adhesives forming a barrier layer between tissues and the hard or impossible to undo nature of these methods. A viable alternative might be electroadhesion using cation and anion pairs, which uses low-voltage DC to firmly attach the two sides, with polarity reversal loosening the connection with no permanent effects. This is what a group of researchers have been investigating for a few years now, with the most recent paper on the topic called Reversibly Sticking Metals and Graphite to Hydrogels and Tissues by [Wenhao Xu] and colleagues published this year in ACS Central Science . This follows on the 2021 study published in Nature Communications by [Leah K. Borden] and colleagues titled Reversible electroadhesion of hydrogels to animal tissues for suture-less repair of cuts or tears . In this stud...

A Single Transistor Solid State Tesla Coil

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Tesla coils are one of those builds that capture the interest of almost anybody passing by. For the naΓ―ve constructor, they look simple enough, but they can be finicky beasts—beasts that can bite if not treated with respect. [Mirko Pavleski] has some experience with them and shares it with us over on Hackaday.io . One of the first big improvements of this build style is the shift from the originally used spark gap commutator to that of a direct AC drive via a MOSFET oscillator. This improves the primary drive power for its size and eliminates that noisy spark gap. That’s one less source of broadband RF noise and the audible racket these produce. You can buy ready-wound secondary coils from the usual CN suppliers The primary side of a Tesla coil is usually a handful of turns of thick wire to handle the current without melting. This build runs at two or three amps, giving a primary power of around 150 Watts. However, this is quite a small unit; with larger ones, the power is muc...

A Practical Guide To Understanding How Radios Work

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How may radios do you own? Forget the AM/FM, GMRS/FRS radios you listen to or communicate with. We’re talking about the multiple  radios and antennae in your phone, your TV, your car, your garage door opener, every computing device you own- you get the idea. It’s doubtful that you can accurately count them even in your own home. But what principles of the electromagnetic spectrum allow radio to work, and how do antenna design, modulation, and mixing affect it? [MichaΕ‚ Zalewski] aka [lcamtuf] aims to inform you with his excellent article Radios, how do they work? A simple illustration compares a capacitor to a dipole antenna. For those of you with a penchant for difficult maths, there’s some good old formulae published in the article that’ll help you understand the physics of radio. For the rest of us, there are a plethora of fantastic illustrations showing some of the less obvious principals, such as why a longer diploe is more directional than a shorter dipole. The article o...

Experiencing Visual Handicaps and Their Impact on Daily Life, With VR

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Researchers presented an interesting project at the 2024 IEEE Conference on Virtual Reality and 3D User Interfaces : it uses VR and eye tracking to simulate visual deficits such as macular degeneration, diabetic retinopathy, and other visual diseases and handicaps. Typical labels and pill bottles can be shockingly inaccessible to a variety of common visual deficits. VR offers a unique method of allowing people to experience the impact of living with such conditions, a point driven home particularly well by having the user see for themselves the effect on simple real-world tasks such as choosing a pill bottle, or picking up a mug. Conditions like macular degeneration (which causes loss of central vision) are more accurately simulated by using eye tracking, a technology much more mature nowadays than it was even just a few years ago. The abstract for the presentation is available here , and if you have some time be sure to check out the main index for all of the VR research demos...

Security Alert: Potential SSH Backdoor Via Liblzma

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In breaking news that dropped just after our weekly security column went live, a backdoor has been discovered in the xz package , that could potentially compromise SSH logins on Linux systems. The most detailed analysis so far seems to be by [Andres Freund] on the oss-security list . The xz release tarballs from 5.6.0 in late February and 5.6.1 on March 9th both contain malicious code. A pair of compressed files in the repository contain the majority of the malicious patch, disguised as test files. In practice, this means that looking at the repository doesn’t reveal anything amiss, but downloading the release tarballs gives you the compromised code. This was discovered because SSH logins on a Debian sid were taking longer, with more CPU cycles than expected. And interestingly, Valgrind was throwing unexpected errors when running on the liblzma library. That last bit was first discovered on February 24th , immediately after the 5.6.0 release. The xz-utils package failed its tests on...

Electrospinning Artificial Heart Valves

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When you think about additive manufacturing, thoughts naturally turn to that hot-glue squirting CNC machine sitting on your bench and squeezing whatever plastic doodad you need. But 3D printing isn’t the only way to build polymer structures, as [Riley] shows us with this fascinating attempt to create electrospun heart valves . Now, you may never have heard of electrospinning, but we’ll venture a guess that as soon as you see what it entails, you’ll have a “Why didn’t I think of that?” moment. As [Riley] explains, electrospinning uses an electric field to build structures from fine threads of liquid polymer solution — he uses polycaprolactone (PCL), a biodegradable polyester we’ve seen used in other medical applications , which he dissolves in acetone. He loads it into a syringe, attaches the positive terminal of a high-voltage power supply to the hypodermic needle, and the negative terminal to a sheet of aluminum foil. The charge turns the PCL droplets into fine threads that accumula...

Retrotechtacular: The IBM 7070

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If you think of IBM mainframe computers, you most likely are thinking of the iconic S/360 or the slightly newer S/370. But what about the 7070 from 1958? It had transistors! It didn’t, however, use binary. Instead, it was a decimal-architecture machine. You can see a lost video of the machine below. It was originally slated to upgrade the older IBM 650 and 705 computers. However, it wasn’t compatible with either, so IBM had to roll out the IBM7080, which was compatible, at least, with the 705. Both machines could run 650 code via emulation. Hardly a personal computer, this beast weighed over 23,000 pounds and cost a cool $813,000. Most companies leased it, though for a mere $17,400 a month. For that price, you got 5,000 words of core memory that could each hold ten decimal digits and a sign bit. The CPU ran at a stately 27 kHz. Hey, this was 1958, after all. One innovation was that card readers and printers connected to the computer through a “synchronizer” that buffered between t...

Saving a Clock Radio with an LM8562

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Smart phones have taken the place of a lot of different devices especially as they get more and more powerful. GPS, music and video player, email, and of course a phone are all functions tied up in these general-purpose devices. Another casualty of the smart phone revolution is the humble bedside alarm clock as its radio, alarm, and timekeeping functionalities are also provided by modern devices. [zst123] has a sentimental attachment to the one he used in the 00s, though, and set about restoring it to its former glory . Most of the issue with the clock involved drift with the timekeeping circuitry. Since it wasn’t accurately keeping the time anymore, losing around 10 minutes a day, the goal to save it was to use NTP to get the current time and a microcontroller to make the correction automatically. Rather than replace everything in the clock except the display, [zst123] is using the existing circuit board and adding an ESP8266 to grab the time from the Internet. A custom driver board...

Exploring The Sega Saturn’s Wacky Architecture

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Sega Saturn mainboard with main components labelled. More RAM is found on the bottom, as well. (Credit: Rodrigo Copetti) In the annals of game console history, the Sega Saturn is probably the most convoluted system of all time, even giving the Playstation 3 a run for its rings. Also known as the system on which Sega beached itself before its Dreamcast swansong, it featured an incredible four CPUs, two video processors, multiple levels and types of RAM, all pushed onto game studios with virtually no software tools or plan how to use the thing. An introduction to this console’s architecture is provided by [Rodrigo Copetti] , which gives a good idea of the harrowing task of developing for this system. Launched in Japan in 1994 and North America and Europe in 1995, it featured a double-speed CD-ROM drive, Hitachi’s zippy new SH-2 CPU (times two) and some 3D processing grunt that was intended to let it compete with Sony’s Playstation. The video and sound solutions were all proprietary...

Retrogadgets: Butler in a Box

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You walk into your house and issue a voice command to bring up the lights and start a cup of coffee. No big deal, right? Siri, Google, and Alexa can do all that. Did we mention it is 1985? And, apparently, you were one of the people who put out about $1,500 for a Mastervoice “ Butler in a Box ,” the subject of a Popular Science video you can see below. If you think the box is interesting, the inventor’s story is even stranger. [Kevin] got a mint-condition Butler in a Box from eBay. How did it work, given in 1983, there was no AI voice recognition and public Internet? We did note that the “appliance module” was a standard X10 interface. Of course, X10 automation was common enough in those days. But the voice command feature was certainly wrong. You did have to use a cassette tape to train the box to your voice. The whole setup was pretty intense and took about 25 minutes just for a simple single device. In addition to the interesting technology, the story of [Gus Searcy] and his pa...

Homebrew GPU Tackles Quake

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Have you ever wondered how a GPU works? Even better, have you ever wanted to make one? [Dylan] certainly did, because he made FuryGPU — a fully custom graphics card capable of playing Quake  at over 30 frames per second. As you might have guessed, FuryGPU isn’t in the same league as modern graphics card — those are made of thousands of cores specialized in math, which are then programmed with whatever shaders you want. FuryGPU is a more “traditional” GPU, it has dedicated hardware for all the functions the GPU needs to perform and doesn’t support “shader code” in the same way an AMD or NVIDIA GPU does. According to [Dylan], the hardest part of the whole thing was writing Windows drivers for it. On his blog, [Dylan] tells us all about how he went from the obligatory [Ben Eater] breadboard CPU to playing with FPGAs to even larger FPGAs to bear the weight of this mighty GPU. While this project isn’t exactly revolutionary in the GPU world, it certainly is impressive and we impatien...

Retrotechtacular: TOPS Runs the 1970s British Railroad

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How do you make the trains run on time? British Rail adopted TOPS, a computer system born of IBM’s SAGE defense project, along with work from Standford and Southern Pacific Railroad. Before TOPS, running the railroad took paper. Lots of paper, ranging from a train’s history, assignments, and all the other bits of data required to keep the trains moving. TOPS kept this data in real-time on computer screens all across the system. While British Rail wasn’t the only company to deploy TOPS, they were certainly proud of it and produced the video you can see below about how the system worked. There are a lot of pictures of old big iron and the narrator says it has an “immense storage capacity.”  The actual computers in question were a pair of IBM System/370 mainframes that each had 4 MB of RAM. There were also banks of 3330 disk drives that used removable disk packs of — gasp — between 100 and 200 MB per pack. As primitive and large as those disk drives were, they pioneered many famil...

FLOSS Weekly Episode 776: Dnsmasq, Making the Internet Work Since 1999

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This week Jonathan Bennett and Simon Phipps sit down with Simon Kelley to talk about Dnsmasq! That’s a piece of software that was first built to get a laptop online over LapLink, and now runs on most of the world’s routers and phones. How did we get here, and what does the future of Dnsmasq look like? For now, Dnsmasq has a bus factor of one, which is a bit alarming, given how important it is to keeping all of us online. But the beauty of the project being available under the GPL is that if Simon Kelley walks away, Google, OpenWRT, and other users can fork and continue maintenance as needed. Give the episode a listen to learn more about Dnsmasq, how it’s tied to the Human Genome Project, and more! Did you know you can watch the live recording of the show right in the Hackaday Discord ? Have someone you’d like use to interview? Let us know, or contact the guest and have them contact us! Next week we’re chatting with Joshua Colp about dnsmasq. Direct Download in DRM-free MP3. I...

3D Printing with (Ersatz) Moon Dust

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When the people of Earth set up bases on the moon, you can imagine that 3D printing will be a key enabling technology. Of course, you could ship plastic or other filament at great cost. But what if you could print with something you can already find on the moon? Like moon dust. NASA thinks it is possible and has been doing tests on doing just that. Now [Virtual Foundry] wants to let you have a shot at trying it yourself. It doesn’t really contain moon dust, but their Basalt Moon Dust Filamet has a similar composition. You can see a video about the material below. It isn’t cheap, but it is probably cheaper than going up there to get some yourself. At least for now. The company is known for making PLA with various metal and ceramic materials. Like their other filaments, you print it more or less like PLA, although you need a large hardened nozzle, and they suggest a prewarmer to heat the filament before going to the hot end. They recommend printing at 210C and 135% flow rate. The ma...

2024 Home Sweet Home Automation: [HEX]POD – Climate Tracker and Digital Nose

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[eBender] was travelling India with friends, when one got sick. Unable to find a thermometer anywhere during COVID, they finally ended up in a hospital. After being evacuated back home, [eBender] hatched an idea to create a portable gadget featuring a few travel essentials: the ability to measure body temperature and heart rate, a power bank and an illumination source. The scope evolved quite a lot, with the concept being to create a learning platform for environmental multi-sensor fusion. The current cut-down development kit hosts just the air quality measurement components, but expansion from this base shouldn’t be too hard. ML for Hackers: Fiddle with that Tensor Flow This project’s execution is excellent, with a hexagon-shaped enclosure and PCBs stacked within. As everyone knows, hexagons are the bestagons . The platform currently hosts SCD41 and SGP41 sensors for air quality, a BME688 for gas detection, LTR-308 for ambient light and motion, and many temperature sensors. On ...