MEMS Teardown And Macroscopic Models

March 6, 2023 by 18 Comments

There is a bit of a paradox when it comes to miniaturization. When electronics replaced mechanical devices, it was often the case that the electronic version was smaller. When transistors and, later, ICs, came around, things got smaller still. However, as things shrink to microscopic scales, transistors don’t work well, and you often find — full circle — mechanical devices. [Breaking Taps] has an investigation of a MEMS chip. MEMS is short for Micro Electromechanical Systems, which operate in a decidedly mechanical way. You can see the video, which has some gorgeous electron microscopy, below. The best part, though, is the 3D-printed macroscale mechanisms that let you see how the pieces work.

Decapsulating the MPU-6050 was challenging. We usually mill a cavity on the top of an IC and use fuming nitric on a hot plate (under a fume hood) to remove the remaining epoxy. However, the construction of these chips has two pieces of silicon sandwiched together, so you need to fully expose the die to split them apart, so our usual method might not work so well. Splitting them open, though, damaged parts of the chip, so the video shows a composite of several devices.

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What Does An Electron Look Like?

March 6, 2023 by 23 Comments

In school, you probably learned that an atom was like a little solar system with the nucleus as the sun and electrons as the planets. The problem is, as [The Action Lab] points out, the math tells us that if this simplistic model was accurate, matter would be volatile. According to the video you can see below, the right way to think about it is as a standing wave.

What does that mean? The video shows a very interesting demonstrator that shows how that works. You can actually see the standing waves in a metal ring. This is an analog — still not perfect — for the workings of an atom. An input frequency causes the ring to vibrate, and at specific vibration frequencies, a standing wave develops in the ring.

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What’s Going To Happen To Legacy Broadcast Bands When The Lights Go Out?

March 6, 2023 by 215 Comments

Our smartphones have become our constant companions over the last decade, and it’s often said that they have been such a success because they’ve absorbed the features of so many of the other devices we used to carry. PDA? Check. Pager? Check. Flashlight? Check. Camera? Check. MP3 player? Of course, and the list goes on. But alongside all that portable tech there’s a wider effect on less portable technology, and it’s one that even has a social aspect to it as well. In simple terms, there’s a generational divide that the smartphone has brought into focus, between older people who consume media in ways born in the analogue age, and younger people for whom their media experience is customized and definitely non-linear.

The Kids Just Don’t Listen To The Radio Any More

A 1957 American family watching TV
We’re guessing this is no longer a scene played out in many homes. Evert F. Baumgardner, Public domain.

The effect of this has been to see a slow erosion of the once-mighty reach of radio and TV broadcasters, and with that loss of listenership has come less of a need for the older technologies they relied on. Which leaves a fascinating question here at Hackaday, what is going to happen to all that spectrum? Indeed, there’s a deeper question behind all that, is lower frequency spectrum even that valuable any more?

In the old days, we had analogue TV in several-MHz-wide channels spread across a large part of the UHF bands and some smaller chunks of VHF. Among that we had 20 MHz of FM broadcasting around the 100 MHz mark, and disregarding shortwave, then a MHz of AM down around 1 MHz. Europeans got a bonus band down there too: we’ve got Long Wave, over 100 kHz of AM goodness roughly centered around 200 kHz.

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A yellow computer with a black keyboard and a small monochrome LCD screen

Low Power Challenge: The PotatoP Runs Lisp For Months Without Recharging

March 6, 2023 by 53 Comments

A common complaint among laptop users is that while battery technology has vastly improved over the past decades, a simulltaneous shrink in form factors has meant that a typical laptop today doesn’t last much longer on a battery charge than one from the early 2000s. But it doesn’t have to be that way, as [Andreas Eriksen] demonstrates with his entry for the Low Power Challenge. The PotatoP is a portable computer that should be able to run for about two years on a single battery charge, and can be topped up through an integrated solar panel.

Granted, it doesn’t have the processing power of even the cheapest laptop you can buy today, but it’s perfectly fine for [Andreas]’s use case. He’s a Lisp hacker, and a Sparkfun RedBoard Artemis can run uLisp just fine on its 48 MHz Cortex-M4F processor. The operating environment is very basic though, even requiring [Andreas] to write his own text editor, called Typo, to give him editing luxuries like backspace functionality and a movable cursor.

The Artemis board is very power-efficient by itself – typical power consumption is less than 1 mA. [Andreas] added a simple monochrome black-and-white LCD screen capable of displaying 53 columns of text, plus an SD card reader for data storage, and designed a sleek 3D-printed case to hold everything together. When running a typical piece of code, the entire system uses around 2.5 mA, which translates to about 125 days of continuous run-time on the beefy 12000 mAh lithium battery. Add a bit of solar power, plus a more realistic eight-hour working day, and the two year runtime estimated by [Andreas] appears entirely reasonable.

This has to be one of the most power-efficient portables we’ve ever seen, and one running Lisp at that. Despite its age, Lisp keeps popping up in interesting custom computers like the Lisperati1000 cyberdeck and The Lisp Badge.

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The Future Of RISC-V And The VisionFive 2 Single Board Computer

March 6, 2023 by 47 Comments

We’ve been following the open, royalty-free RISC-V ISA for a while. At first we read the specs, and then we saw RISC-V cores in microcontrollers, but now there’s a new board that offers enough processing power at a low enough price point to really be interesting in a single board computer. The VisionFive 2 ran a successful Kickstarter back in September 2022, and I’ve finally received a unit with 8 GB of ram. And it works! The JH7110 won’t outperform a modern desktop, or even a Raspberry Pi 4, but it’s good enough to run a desktop environment, browse the web, and test software.

And that’s sort of a big deal, because the RISC-V architecture is starting to show up in lots of places. The challenge has been getting real hardware that’s powerful enough to run Linux and compile software on, that doesn’t cost an arm and a leg. If ARM is an alternative architecture, then RISC-V is still an experimental one, and that is an issue when trying to use the VF2. That’s a theme we’ll repeat a few times, but the thing to remember here is that getting more devices in the wild is the first step to fixing things. Continue reading “The Future Of RISC-V And The VisionFive 2 Single Board Computer” →

A Pi Pico plugged into a breadboard, with jumpre wires going away from its pins to an SPI flashing clip, that's in turn clipped onto an SPI flash chip on a BeagleBone board

Programming SPI Flash Chips? Use Your Pico!

March 6, 2023 by 10 Comments

At this point, a Pi Pico is equivalent to a bag full of programmers and debugging accessories. For instance, when you want to program an SPI flash chip, do you use one of those wonky CH341 dongles, or perhaps, even a full-on Raspberry Pi with a Linux OS? If so, it might be time to set those two aside – any RP2040 board can do this now. This is thanks to work of [stacksmashing] who implemented serprog protocol for the RP2040, letting us use a Pi Pico with stock flashrom for all our SPI flash chip needs.

After flashing the code to your RP2040 board, all you need to do is to wire your flash chip to the right pins, and then use the serprog programmer type in your flashrom commandline – instructions are available on GitHub along with the code, as you’d expect. Don’t feel like installing flashrom, or perhaps you happen to run Windows and need a flasher in a pinch? [stacksmashing] has a WebSerial-based SPI flasher tool for you, too, and shows it off with a fancy all-the-pinouts board of his own making.

This kind of tool is indispensable – you don’t need to mod one of these CH341 programmers to fix the bonkers 5 V default IO, or keep an entire Linux computer handy when you likely already have one at your fingertips. All in all, yay for one more RP2040 trick up our sleeve – this SPI flashing helper joins an assortment of applets for SWD, JTAG, UART, I2C and CAN, and in a pinch, your Pi Pico will also work as a digital and analog logic analyzer or an FPGA playground.

 

Adversarial IR Hoodie Lets You Own The Night In Anonymity

March 6, 2023 by 75 Comments

If you’re in the market for something to obfuscate your nefarious nocturnal activities, rejoice — this adversarial infrared hoodie may be just what you’re looking for.

Not that we condone illegal activities, of course, and neither does artist [Mac Pierce], who created “The Camera-Shy Hoodie.” His purpose seems to be exploring the nature of the surveillance state, or rather to perplex it in the name of anonymity. The idea is simple — equip a standard hoodie with a ring of super-bright IR LEDs, and control them with an RP2040.

We’ve seen blinding hoodies before, but here the LEDs strobe on and off in one of three different patterns, all of which are timed to confound the autoexposure mechanism in just about any surveillance camera by not giving it time to adjust to the rapidly and drastically changing light level. The result is near-total obfuscation of the wearer’s facial features, at least when the camera is in night-vision mode. Check out the results in the video below.

There are some nice touches to [Mac]’s approach, like aluminum PCBs for the LEDs and the use of soldered-on fabric snaps to attach them to the inside of the hoodie, making them easy to remove for laundering. With the LEDs peeking through holes in the fabric, the hoodie looks pretty run-of-the-mill — until, of course, night falls and the USB battery bank in the hoodie’s pocket powers up the light show.

Granted, this won’t exactly help you avoid detection — the big ball of light around your head will be instantly seen by even the most casual observer. But at least it makes it easier to keep your face to yourself. And it won’t help much in daylight — for that, you might want something a little more like this passive adversarial ugly sweater.

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