If you’ve made a robot or played around with electronics before, you might have used a time-of-flight laser distance sensor before. More modern ones detect not just the first reflection, but analyze subsequent reflections, or reflections that come in from different angles, to infer even more about what they’re looking at. These transient sensors usually aren’t the most accurate thing in the world, but four people from the University of Wisconsin managed to get far more out of one using some clever math. (Video, embedded below.)
The transient sensors under investigation here sends out a pulse of light and records what it receives from nine angles in individual histograms. It then analyzes these histograms to make a rough estimate of the distance for each direction. But the sensor won’t tell us how it does so and it also isn’t very accurate. The team shows us how you can easily get a distance measurement that is more accurate and continues by showing how the nine distance estimates can even distinguish the geometry it’s looking, although to a limited extent. But they didn’t stop there: It can even detect the albedo of the material it’s looking at, which can be used to tell materials apart!
USB-C Power Delivery has definitely made the big mess of wires a bit smaller but not all cables are created equal — some of them can handle upwards of 100 W while the cheapest can handle only 10. To accommodate this, USB-C cables need to actively tell both ends what their capabilities are, which turns an otherwise passive device into a hidden chip in a passive looking cable.
[Greg Davill] has decided to unravel the mystery of why your laptop isn’t charging by creating a USB-PD sniffer. Based on Google’s Twinkie sniffer, the FreshTwinkie makes the design more accessible by reducing the number of layers in the PCB and replacing the BGA variant of the STM32 for a more DIY-friendly QFN version. Interestingly, this isn’t the first time we’ve seen somebody try and simplify the Twinkie; back in 2021, the Twonkie from from [dojoe] hit a number of similar notes.
USB-C Power Delivery is just one of many protocols spoken over the CC pins, and the FreshTwinkie might be able to detect when some of those are enabled and why or why not. With future development, it could potentially provide useful information as to why a Thunderbolt 4 or tunneled PCIe device isn’t working correctly.
Sound cards used to be a big part of gaming machines in the 90s and 2000s but have largely gone extinct in the wake of powerful CPUs doing the sound themselves. Sound cards were expensive back then and, because the good ones weren’t very common, are expensive still for the retro gamer. But if you don’t need the real thing, [polpo] has you covered with his RP2040-based ISA sound card.
The PicoGUS, as he calls it, primarily serves to replace the Gravis UltraSound with modern components at a low cost. It uses the RP2040’s PIO to attach to an ISA bus and the RP2040’s dual-core power to synthesize the audio for its primary target, but also the AdLib (OPL2), CMS/Game Blaster and Tandy 3-Voice. [polpo] sells the PicoGUS on his Tindie store, but since it’s open source, you can of course just make your own.
Although “work-in-progress”, the PicoGUS is very useful to the right person and a perfect demonstration of how the RP2040’s PIO can be used to interface with almost any type of protocol.
Some of our readers may know about Zork (and 1, 2, 3), the 1977 text adventure originally written for the PDP-10. The game has been public domain for a while now, but recently, the interpreters for several classic 1980s machines have also appeared on the internet.
What’s the difference? Zork is not a PDP-10 executable, it’s actually a virtual machine executable, which is in turn run by an interpreter written for the PDP-10. For example, Java compiles to Java bytecode, which runs on the Java virtual machine (but not directly on any CPU). In the same way, Zork was compiled to “Z-machine” program files, called ZIP (which was of course used in 1990 by the much more well known PKZIP). To date, the compiler, “Zilch” has not been released, but the language specification and ZIP specifications have, which has led some people to write custom ZIP compilers, though with a different input language.
The world’s smallest hydraulic jack is a tiny hand-machined model made out of tiny pieces of iron, brass and copper. But here’s the kicker: It’s a real hydraulic jack with real hydraulic fluid! At 1/5th scale, it obviously isn’t as strong as a full-size jack, but it can still easily lift an impressive 24 soda cans! Switching between the lathe and mill, [Maker B] shows how all the parts of the jack are made from stock metal in detail, and even explains in simple terms how a hydraulic jack works in this masterpiece of a video.
The Intel 4004 was among the first microprocessors and one of the first to use the MOS silicon-gate technology. In the decades long race to build bigger CPUs, it’s been mostly forgotten. Forgotten that is, until [Klaus Scheffler] supersized it over ten-fold!
The project took about 2 years to complete and re-creates it faithfully – all 2,300 transistors included – enough to run software written for the Intel 4004. But the idea for this project isn’t unique and dates all the way back to 2000, so what gives? Turning a bunch of masks for silicon fabrication into a schematic is actually harder than it seems! [Tim McNerney] originally came up with the idea to make a giant 4004 for its “35th anniversary”. [Tim] managed to convince Intel to give him schematics and other drawings and would in return make an exhibit for Intel’s museum. With the schematic straight from [Federico Faggin], software analysis tools from [Lajos Kintli] and [Klaus Scheffler] to actually build the thing, they did what [Federico] did in one year without CAD, but in two with modern tools.
Necklaces aren’t often very high-tech, mostly because of the abuse they have to go through being worn. This was obviously a problem that needed solving, so [Matt Venn] decided to change that by making a necklace out of ASICs just in time for Supercon.
Although this isn’t the first time [Matt] made such a necklace, he though his previous one was “too hip-hop” and not enough “15 million dollar Nikon Lithography Stepper”. Obviously, this means designing the whole chain, art included, from scratch with the blinkenlights to match. Together with [Pat Deegan] and [Adam Zeloof], the team created a beautiful technopunk necklace with art on every chain link and of course a real silicon wafer with a RISC-V tapeout from 2022 on it.
With [Adam] doing modeling for the chain links, and [Pat] and [Matt] designing the electronics required for the mandatory blinkenlights, and some last-minute soldering and assembling the project was finished just in time for Supercon, where it fit right in with all the other blinkenlights. It even runs on one of the RISC-V cores from the same tapeout as the central wafer!