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Showing posts from November, 2025

A Deep Dive into Using PIO and DMA on the RP2350

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Here’s a fun rabbit hole to run down if you don’t already have the RP2040/RP2350 PIO feather in your cap: how to serve data without CPU intervention using PIO and DMA on the RP2350 . If you don’t know much about the RP2040 or RP2350 here’s the basic run down: the original Raspberry Pi Pico was released in 2021 with the RP2040 at its heart, with the RP2350 making its debut in 2024 with the Pico 2 . Both microcontrollers include a feature known as Programmed I/O (PIO), which lets you configure tiny state machines and other facilities (shift registers, scratch registers, FIFO buffers, etc) to process simple I/O logic, freeing up the CPU to do other tasks. The bottom line is that you can write very simple programs to do very fast and efficient I/O and these programs can run separately to the other code running on your micro. In the video below, [piers] explains how it works and how he’s used it in his One ROM project. This is the latest installment from [piers rocks] whose One ROM pro...

Retrotechtacular: The $550K Video Conferencing System Used to Make Bee Movie

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The modern office environment has shifted in recent years. Employees are routinely asked to collaborate with co-workers half way around the globe and be camera ready, or whatever passes for webcam ready, in order to telecommute when they are out of office. Every office laptop, tablet, or cell phone these days comes equipped with some sort of camera sensor capable of recording at HD resolution. Twenty years ago, that was not the case. Though tech conglomerates like HP had a different idea of teleconferencing to sell back in 2005 dubbed the Halo Collaboration Studio . The Halo Studio was a collaboration between HP and Dreamworks that was used during the production of Bee Movie. Studio heads at Dreamworks thought it necessary to install the HP teleconferencing solution inside the New York office of Jerry Seinfeld, the writer of the film, as to allow him to avoid long trips to Dreamworks production offices in Los Angeles. According to the HP Halo Collaboration Studio brochure , “Halo ac...

Raise Bikes to the Heavens with Humble Garage Door Opener

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Biking can be an incredibly rewarding hobby, but what do you do with all of your expensive pieces of metal and composite when you aren’t hitting the trails? They take up space that you could use for more bikes! [Chaz] figured there had to be a better way and discovered the unlikely solution of the humble garage opener . Garage doors are made to lift high with moderate weight, exactly what one would expect from a bike lift. If you have high ceilings in your garage or wherever else you store your bikes there can’t be much easier than pushing a button to get your bike out of the way. To assemble the unusual bike rack, [Chaz] mounted the motor to the wall with a few scraps of wood, and built a wooden platform that rides along the rail. This additional board allows you to use a traditional bike wheel rack to gently raise the bike. While initially [Chaz] had some questionable results, this was quickly resolved with removing the rotational elements of the mount and allowing a slight slant ...

Has Steampunk Delivered the Hoverboard?

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The hoverboard, one of the teen crazes of the last decade, is both a marvel of technology and a source of hacker parts that have appeared in so many projects on these pages. It contains an accelerometer or similar, along with a microcontroller and a pair of motor controllers to drive its in-wheel motors. That recipe is open to interpretation of course and we’ve seen a few in our time, but perhaps not quite like this steampunk design from [Skrubis]. It claims a hoverboard design with no modern electronics, only relays, mercury switches, and neon bulbs. The idea is that it’s a hoverboard from 1884 using parts available in that era, hence there’s talk of telegraph relays and galvanomic piles. The write-up is presented in steampunk-style language which if we’re honest makes our brain hurt, but the premise is intriguing enough to persevere. As far as we can see it uses a pair of relays and a transformer to make an oscillator, from which can be derived the drive for a 3-phase motor. This ...

DIY Light Panels Work With Home Assistant

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There are a few major companies out there building colorful LED panels you can stick on your wall for aesthetic purposes. Most commercial options are pretty expensive, and come with certain limitations in how they can be controlled. [Smart Solutions For Home] has whipped up a flexible DIY design for decorating your walls with light that is altogether more customizable. In this case, the DIY light panels ape the hexagonal design made popular by brands like Nanoleaf. In this case, each hexagon panel runs an ESP32 microcontroller, which controls a series of WS2812 addressable LEDs. This allows each panel to glow whatever color you like, and they’re arranged in an XY grid to enable you to light individual panels with a range of different geometric effects. The benefit of having a full microcontroller on each panel is that they can act quite independently—each one able to be used as a smart light, an notification display, or even as a physical button, all integrated with Home Assistant. ...

On the Benefits of Filling 3D Prints With Spray Foam

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Closed-cell self-expanding foam (spray foam) is an amazing material that sees common use in construction. But one application that we hadn’t heard of before was using it to fill the internal voids of 3D printed objects. As argued by [Alex] in a half-baked-research YouTube video , this foam could be very helpful with making sure that printed boats keep floating and water stays out of sensitive electronic bits. It’s pretty common knowledge by now that 3D printed objects from FDM printers aren’t really watertight. Due to the way that these printers work, there’s plenty of opportunity for small gaps and voids between layers to permit moisture to seep through. This is where the use of this self-expanding foam comes into play, as it’s guaranteed to be watertight. In addition, [Alex] also tests how this affects the strength of the print and using its insulating properties. The test prints are designed with the requisite port through which the spray foam is injected as well as pressure rel...

A Flexible Light Inspired by IKEA

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The IKEA SMÅSNÖRE is a flexible silicone rod with an embedded LED strip, attached at each end to a base. It’s eye-catching enough, and it has the useful property of providing a diffuse light from multiple angles that makes it a promising candidate for a work lamp. That’s enough for [Daniel James] to create his own lamp on a similar vein . The electronics of his lamp are straightforward enough: a 12 volt LED strip whose brightness is controlled by a Pi Pico in response to a potentiometer as a brightness control. It’s not quite stiff enough to form the arch itself, so he’s created a 3D printed chain that forms the structure of the lamp. Similar to a bicycle chain in the way it’s constructed, it has individual links that slot together and pivot. The electronics are in the printed base at one end. We like this lamp a lot, for the light it gives on the bench and for the ingenuity of the printed chain. We might even make one for ourselves. from Blog – Hackaday https://ift.tt/bu4wKpa

3D Printing for the Hospital Setting

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Surgery is hard, there is a reason why school is so long for the profession. Making the job easier and smoother for both patients and surgeons is valuable for all parties, which is why [Mayo Clinic] is now working on including 3D printing into its more regular medicine pipeline . Prepping for surgery often requires examining CT scans of patients to figure out, well, what they’re even going to be doing. Every body is different, and complex surgical procedures require checking to see where certain organs or features are located. This can be made much easier with a physical model of where the bones, organs, or nerves are specifically located in a patient. While this isn’t true in every case of treatment, there are even cancerous cases where custom equipment can be used to decrease side effects, such as mini-beam collimator adapters. What if you could use the same pipeline to print what was lost from certain procedures? In a mastectomy, the breast tissue is removed, which can cause neg...

Live Train Departure Screens Keep You Abreast of Transit Developments

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If you want to know when the train is coming, you could pull up a webpage on your phone, or walk all the way to the station to look at the displays there. Or, like [eastfamilyreddish], you could build a neat little train info display to decorate your desktop instead. The build is based on the work of [gadec-uk] —who developed a train information display some time ago. It’s based around an ESP32 D1 Mini, paired with a 256 x 64 OLED screen to display relevant train information. It accesses a National Rail API for train status information—known as the Darwin LDBWS (Live Departure Board Webservice). Configuration is via a web GUI hosted by the ESP32 itself. [eastfamilyreddish] took the concept further by adapting this hardware into a more pleasing form. The ESP32 and OLED screen are built into a neat little hanging sign setup that apes one you might expect to see at a real railway station. You might expect that 3D printing was involved, but instead, this was achieved with lasercut parts...

Build Your Own Compact Temp Gun

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Sometimes you need to know what temperature something is, but you don’t quite want to touch it. At times like these, you might want a temp gun on hand to get a good reading, like the one [Arnov Sharma] built. The build is a relatively simple one, and is based around an Waveshare ESP32 C6 development module that comes with a small LCD screen out of the box. The microcontroller is set up to read an MLX90614 infrared temperature sensor. This device picks up the infrared energy that is emitted by objects relative to their temperature. The sensor has a great range—from -70 C to 380 C. The readouts from this sensor are then displayed on the screen. Battery power is from a small 600 mAh LiPo cell, which is managed by a IP5306 charge module. It’s worth noting that these infrared temperature sensors aren’t infallible devices. The temperature they perceive is based on certain assumptions about factors like an objects emissivity. Thus, they don’t always give accurate readings on metallic or s...

USB DAC Comes With Graphic EQ

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[shiura] had a problem — they wanted a nice high-quality audio output for their computer, but they didn’t fancy any of the DACs that were readily available on the market. They specifically wanted one that was affordable, capable, and included a graphic equalizer so they could simply hook it up to a regular amplifier and dial in the perfect sound. When they couldn’t find such a device, they decided to build their own. The build is based around a Raspberry Pi Pico, chosen for its feature set that makes it easy to configure as a USB audio device. It’s paired with a Waveshare Pico Audio module, which is based on the PCM5101A stereo DAC and slots neatly on top of the microcontroller board. An SPI-controlled LCD screen was also fitted in order to display the graphic equalizer interface that [shiura] whipped up. The project write-up explains the code required to implement the equalizer in detail. A four-channel equalizer was possible on the original Pi Pico (RP2040), while upgrading to a mo...

US Patent Changes Promise Severe Consequences

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When someone creates a US patent, they go through a review process to stop the most blatant copies from previous patents or pre-existing work. After this, you may still have bad patents get through, which can be removed through litigation or publicly accessible methods such as Inter Partes Review (IPR). The latter of which is planned to be changed as we know it in the near future. IPR is a method where an individual can claim that an existing patent is invalid due to pre-existing work, such as something the individual should have creative ownership over. While there is always the litigation method of removing blatantly fraudulent patents, a small business or the average person is unlikely to have the funds. New regulations are changing how IPRs can be filed in some substantial ways. Now, if someone files an IPR, they give up the right to future litigation on their rights over a patent. This is obviously not ideal for someone who may have their own products on the line if an IPR is...

Designing PLA to Hold Over a Metric Ton

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There’s never been such a thing as being “too competitive” when it comes to competition. This is something that [Tom Stanton] from Tim Stanton (wait, what now), [Tom]’s 2nd channel, took to heart for Polymaker’s 3D design challenge. The goal was simple: a single 3D printed part to hold as much weight as possible . While seemingly simple, when considering the requirements, including a single print in addition to being able to open up for the mounts, the challenge gets exponentially more complicated. While the simplest and strongest joint would be a simple oval for uniform stress, this isn’t possible when considering the opening requirements. This creates a need for slightly more creativity. [Tom] starts out with two flat C-shaped geometries to test his design. The design includes teeth specially placed to allow the forces to increase their own strength as force is applied. Flat features have the unfortunate quality of being able to slide across each other rather easily, which was the...

Hydrofoil Bikes Are Harder To Build Than You Think

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Hydrofoils are perhaps best known for their application on boring ferries and scary boats that go too fast. However, as [RCLifeOn] demonstrates, you can also use them to build fun and quirky personal watercraft. Like a hydrofoil bike! Only, there are some challenges involved. Hydrofoils work much like airfoils in air. The shape of the foil creates lift, raising the attached vehicle out of the water. This allows the creation of a craft that can travel more quickly because the majority of its body is not subject drag from the water. The key is to design the craft such that the hydrofoils remain at the right angle and depth to keep the craft lifted out of the water while remaining stable. The hydrofoil bike is created out of a combination of plywood, foam, and 3D printed components. It uses a powerful brushless motor for propulsion, and that’s about it. Sadly, despite the simplicity, it wasn’t an instant success. As you might expect, balancing on the bike is quite difficult, particula...

One-Way Data Extraction For Logging On Airgapped Systems

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If you want to protect a system from being hacked, a great way to do that is with an airgap. This term specifically refers to keeping a system off any sort of network or external connection — there is literally air in between it and other systems. Of course, this can be limiting if you want to monitor or export logs from such systems. [Nelop Systems] decided to whip up a simple workaround for this issue, creating a bespoke one-way data extraction method. The concept is demonstrated with a pair of Raspberry Pi computers. One is hooked up to critical industrial control systems, and is airgapped to protect it against outside intruders. It’s fitted with an optocoupler, with a UART hooked up to the LED side of the device. The other side of the optocoupler is hooked up to another Raspberry Pi, which is itself on a network and handles monitoring and logging duties. This method creates a reliable one-way transmission method from the airgapped machine to the outside world, without allowing d...

Benchmarking Chinese CPUs

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When it comes to PCs, Westerners are most most familiar with x86/x64 processors from Intel and AMD, with Apple Silicon taking up a significant market share, too. However, in China, a relatively new CPU architecture is on the rise. A fabless semiconductor company called Loongson has been producing chips with its LoongArch architecture since 2021. These chips remain rare outside China, but some in the West have been benchmarking them. [Daniel Lemire] has recently blogged about the performance of the Loongson 3A6000 , which debuted in late 2023. The chip was put through a range of simple benchmarking tests, involving float processing and string transcoding operations. [Daniel] compared it to the Intel Xeon Gold 6338 from 2021, noting the Intel chip pretty much performed better across the board. No surprise given its extra clock rate. Meanwhile, the gang over at [Chips and Cheese] ran even more exhaustive tests on the same chip last year . The Loongson was put through typical tasks like...

Building a Low-Cost Satellite Tracker

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Looking up at the sky just after sunset or just before sunrise will reveal a fairly staggering amount of satellites orbiting overhead, from tiny cubesats to the International Space Station. Of course these satellites are always around, and even though you’ll need specific conditions to view them with the naked eye, with the right radio antenna and only a few dollars in electronics you can see exactly which ones are flying by at any time . [Josh] aka [Ham Radio Crash Course] is demonstrating this build on his channel and showing every step needed to get something like this working. The first part is finding the correct LoRa module, which will be the bulk of the cost of this project. Unlike those used for most Meshtastic nodes, this one needs to be built for the 433 MHz band. The software running on this module is from TinyGS , which we have featured here before , and which allows a quick and easy setup to listen in to these types of satellites. This build goes much further into detail...

Elli Furedy Brings Cyberpunk Games to Life

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When you’re designing a bounty hunter game for a five-day cyberpunk live-action-role-play out in the middle of the Mojave desert, you’ve got to bring something extra cool. But [Elli]’s Hackaday Supercon talk isn’t just about the hardware ; it’s as much about the design philosophy behind the game – how you bring something immersive and exciting to hundreds of players. Sandbox Systems The game itself is fairly simple: bounty hunters try to find the bounty, and when they do, they have a quick-draw to see who wins. Everyone is issued a color-coded Portable Data Node device, and when a hunter jacks into a bounty’s Node, a countdown begins, and the first to press the button after the display say “Go” wins. But the simplicity of the game is by design, and [Elli] talks about the philosophy that she and her team followed to make it a success. If you’re designing a conference badge or an immersive game for a large group of people, take note. The first principle is to focus on the people fir...

DIY Test Gear from 1981

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We can’t get enough of [Bettina Neumryn’s] videos. If you haven’t seen her, she takes old electronics magazines, finds interesting projects, and builds them. If you remember these old projects, it is nostalgic, and if you don’t remember them, you can learn a lot about basic electronics and construction techniques. This installment (see below) is an Elektor digital voltmeter and frequency counter from late 1981 . As was common in those days, you could find the PCB layouts in the magazine. In this case, there were two boards. The schematic shows that a counter and display driver chip — a 74C928 — does most of the heavy lifting for the display and the counter. It is easy to understand how the frequency counter works. You clip the input with a pair of diodes, amplify it a bit, square it with a Schmitt trigger, and then, possibly, prescale it using a divider. The voltmeter is a little trickier: it uses a voltage divider, an op amp, and a 555 to convert the voltage to a frequency. O...

Build A High Voltage Supply For Vacuum Tube Work

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If you work on simple digital projects, just about any bench supply will offer the voltage and current you’re looking for. However, if you’re working with valves, you’ll often find yourself needing much higher voltages that can be tricky to source. [Chappy Happy] has shared a design for a simple HV power supply that should prove useful to vacuum tube enthusiasts. The build is fairly basic in nature, lacing together some commonly available parts to generate the necessary voltages for working with common vacuum tubes from a 12 volt DC input. Inside the supply is a UC3843A DC boost converter, set up to output high voltage up to around 300 volts DC, with a ripple filter added for good measure. The output can be adjusted with a knob, with a voltmeter on the front panel. There’s also a 12-volt output, and a LM2596 step down converter to produce 6.3 volts for the filament supply. The whole project is built in an old Heathkit project box, and he demonstrates the supply with a simple single-...

The Zen Must Flow From Arrakis Sand Table

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In  Dune , the Fremen people of Arrakis practice an odd future hybrid religion called “zensunni.” This adds an extra layer of meaning to the title of [Mark Rehorst]’s Arrakis 3.0 sand table, given that the inspiration for the robotic sand table seems to be Zen gardens from Japan. The dunes on the tabletop version of Arrakis owe nothing to sand worms, but are instead created a rolling metal ball. With all workings happening below, it looks quite magical to the uninitiated, but of course it’s not magic: it’s magnets. Just beneath the tabletop and its sands, the steel ball is being dragged along by the magnetic field of a powerful neodynium magnet. That magnet is mounted in a CoreXY motion system that owes more than a little bit to modern 3D printers. Aside from the geometry, it’s using the standard G6 belt we see so often, along with a Duet3D mainboard, NEMA 17 steppers, and many 3D printed parts to hold its aluminum extrusions together. Thanks to that printer-inspired motion sys...

Citizen Science by the Skin of Your Teeth

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If you are a schoolkid of the right age, you can’t wait to lose a baby tooth. In many cultures, there is a ritual surrounding it, like the tooth fairy, a mouse who trades your tooth for a gift, or burying the tooth somewhere significant. But in 1958, a husband and wife team of physicians wanted children’s teeth for a far different purpose: quantifying the effects of nuclear weapons testing on the human body. A young citizen scientist (State Historical Society of Missouri) Louise and Eric Reiss, along with some other scientists, worked with Saint Louis University and the Washington School of Dental Medicine to collect and study children’s discarded teeth. They were looking for strontium-90, a nasty byproduct of above-ground nuclear testing. Strontium is similar enough to calcium that consuming it in water and dairy products will leave the material in your bones, including your teeth. The study took place in the St. Louis area, and the results helped convince John F. Kennedy to sig...