Driving WS2812Bs With Pure Logic

The WS2812B has become one of the most popular addressable LEDs out there. They’re easy to drive from just about any microcontroller you can think of. But what if you have a microcontroller at all? [Povilas Dumcius] decided to try and drive the LEDs with raw logic only.

The project consists of a small board full of old-school ICs that can be used to drive WS2812Bs in a simplistic manner. A 74HC14 Schmitt trigger oscillator provides the necessary beat for this tune, generating an 800 kHz clock to keep everything in time and provide the longer pulse trains that represent logic one to a WS2812B. A phase-shifted AND gate generates the shorter pulses necessary to indicate logic zero. Meanwhile, a binary counter cycles through 24 bits (8 per R, G, and B) to handle color. Pressing each one of the three pushbuttons allows each color channel to be activated or deactivated as desired. It can make the strip red, green, or blue, or combine the channels if you press multiple buttons at once. That’s all the control you get—it would take a bit more logic to enable variable levels of each channel. Certainly within the realms of possibility, though.

We’ve featured some other nifty tricks for driving WS2812Bs in unconventional ways, like using DMA hardware or even I2S audio outputs. If you’ve got your own tricks, don’t hesitate to notify the tipsline. Video after the break.

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Building The Haxocorder

The Haxophone is an open source MIDI saxophone project that has achieved some popularity. It’s caught the attention of [Shieladixon] not because she is a saxophonist but because she plays the recorder and is dissatisfied with existing MIDI recorder peripherals. She’s set about modifying the device to produce the Haxocorder, a better MIDI recorder.

The video below the break is the third of a series, of which part one and part two deal with the Haxophone and the shortcomings of her existing recorder peripheral. She’s replacing the Pi Zero of the Haxophone with a Pi Pico in a Zero form factor, and simplifying its design significantly to remove unnecessary features. The result is a versatile instrument capable at a touch of becoming the full range of recorders, which she demonstrates with some nifty duet work.

The upstream Haxophone project can be found here if you are interested, and we hope she follows this up with a release of her mods to make the Haxocorder. Meanwhile if you feel you might have seen her work before, she’s the brains behind the MIDISID.

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Bionode Is Hand Truck Transformed Into Mobile Computing Lab

[Steven K. Roberts] is the original digital nomad, having designed and built mobile computing for his own use since the 80s. His latest project is Bionode, a portable computing lab built into a hand truck that can accommodate a wide spectrum of needs for a person on the go.

Far more than just a portable computer with wheels and a handle, Bionode is an integrated collection of systems with power management, a sensor suite, multiple computers, NAS for storage, networking, video production tools, and even the ability to be solar charged. [Steven] also uses a laptop, and Bionode complements it by being everything else.

If one truly wishes to be mobile and modular as well as effective, then size and weight begins to be just as important as usability. Everything in Bionode has a purpose, and it currently contains a PC with GPU for local AI and machine learning work, a NAS with 14 TB of storage, an Ubuntu machine, a Raspberry Pi 5 running Home Assistant, another Raspberry Pi 5 for development work, a Raspberry Pi 3 for running his 3D printer, and a Raspberry Pi 4 for SDR (software-defined radio) work. A smart KVM means a single keyboard, mouse, and display can be shared among machines as needed and additional hardware in a thoughtful layout makes audio and video projects workable. Everything is integrated with sensors and Home Assistant with local AI monitoring, which [Steven] likes to think of as the unit’s nervous system.

Bionode is therefore more than just a collection of computers crammed into a hand truck; it’s a carefully-selected array of hardware that provides whatever [Steven] needs.

Give it a look if you want to see what such a system looks like when it’s been designed and assembled by someone who’s “been there, done that” when it comes to mobile computing. Bionode would complement something like a mobile workshop quite nicely; something [Steven] has also done before.


Thanks [Paul] for the tip!

The Curse Of The Everything Device

In theory having a single device that combines the features of multiple dedicated devices is a great idea, saving a lot of space, time and money. However, in reality it mostly means that these features now conflict with each other, force us to deal with more complex devices that don’t last nearly as long, and become veritable vampires for your precious attention.

Whereas in the olden days a phone was just used for phone calls, now it’s also a video and photo camera, multimedia computer, pager, and more, but at any point an incoming phone call can interrupt what you are doing. There’s also always the temptation of doom scrolling on one of the infinite ‘social media’ apps. Even appliances like televisions and refrigerators are like that now, adding ‘smarts’ that also vie for your attention, whether it’s with advertisements, notifications, or worse.

Meanwhile trying to simply do some writing work on your PC is a battle against easy distractions, leading people to flee to the digital equivalent of typewriters out of sheer desperation. Similarly, we increasingly see ‘dumb’ phones, and other single-task devices making a comeback, both as commercial options and as DIY projects by the community.

Are we seeing the end of the ‘everything device’ and the return to a more simple time?

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Easily Replaceable USB-C Port Spawned By EU Laws

The USB-C port has become a defacto connectivity standard for modern devices, largely supplanting the ugly mess of barrel jacks and micro USB connectors that once cursed us. While their reliability is good, they don’t last forever, and can be a pain to replace in most devices if they do fail. However, a new part from JAE Electronics could change that.

The problem with replacing USB connectors in most hardware is that they’re soldered in place. To swap them out, you have to master both desoldering and soldering leads of a rather fine pitch. It’s all rather messy. In the interest of satisfying the EU’s new Ecodesign for Sustainable Products Regulation (ESPR), JAE Electronics has developed a USB-C connector that’s easier to replace. Rather than being soldered in, the part is simply clamped down on to a printed circuit board with small screws. As the part is torqued down, small gold-plated contacts are compressed into pads on the PCB to make the necessary contact.

The connector is fully compatible with USB 4 version 2.0. (Don’t ask us how they number these things anymore.) It comes in single and dual connector versions, and is capable of USB PD EPR at up to 240 W (5A/48V). The part does have some drawbacks—namely, the footprint of the metal-shelled part is somewhat larger than most soldered USB C connectors. Whether this precludes its use is very much an application-specific matter for product engineers to decide.

In any case, if you find yourself designing hardware with heavily-used USB C ports, you might find this part useful. It’s not widely available yet, but some parts should be landing at Mouser in coming months. We’ve explored some of the ways USB-C connectors can be fouled and damaged before, too. Sound off with your opinions on this new part in the comments.

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The Engineering Of A Jimi Hendrix Performance

The guitarist Jimi Hendrix had a unique sound which has influenced countless musicians over the decades. He achieved it through mastery not only of his instrument, but of the complex feedback relationship between amplifier, environment, and guitar — coupled with a series of effects pedals including some then-unique ones made for him. Musical commentators have pored over his work for decades, but a recent piece in IEEE Spectrum is particularly interesting as it examines things from a technical perspective.

It centers around an electrical simulation of Hendrix’s effects chain, and makes an assertion that’s obvious on consideration but not the usual take on a Hendrix performance; that in his hands it became a wave synthesizer rather than the instrument itself. Certainly for anyone with an interest in analogue audio electronics as they pertain to musical synthesis it helps in placing the influence of the different circuits on the sound, and in hearing the familiar performances in a new light.

This isn’t the first time we’ve seen someone take a modelling approach to a guitar effects chain, indeed it’s obvious something missing from the work above is the guitar itself.


Header image: Gemeente Rotterdam (Stadsarchief) CC-0.