Fork And Run: The Definitive Guide To Getting Started With Multiprocessing

Since the early 2000s, the CPU industry has shifted from raw clock speed to core counts. Pat Gelsinger famously took the stage in 2002 and gave the talk the industry needed, stating processors needed specialty silicon or multiple cores to reduce power requirements and spread heat. A few years later, the Core series was introduced with two or four-core configurations to compete with the AMD Athlon 64 x2.

Nowadays, we’re seeing heterogeneous chip designs with big and little cores, chiplets, and other crazy fabrication techniques that are fundamentally the same concept: spread the thermal load across multiple pieces of silicon. This writer is willing to put good money into betting that you’ll see consumer desktop machines with 32 physical cores in less than five years. It might be hard to believe, but a 2013 Intel Haswell i7 came with just four cores compared to the twenty you’ll get in an i7 today. Even an ESP32 has two cores with support in FreeRTOS for pinning tasks to different cores. With so many cores, how to even write software for that? What’s the difference between processes and threads? How does this all work in straight vanilla C98?

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This Simple Light-Controlled Synth Has A Surprisingly Rich Sound

Audio synthesizers can range from vast racks of equipment with modules stitched together by a web of patch cords to a couple of 555s wired together in an Atari punk arrangement. This light-controlled synth comes in closer to the lower extreme of that range, but packs a sonic punch that belies its simplicity.

The project is the latest version of [lonesoulsurfer]’s “Moog Light Synthesizer,” which shares a lot of the circuitry found in his first version a couple of years ago. This one has a lot of bells and whistles, but it all starts with a PWM oscillator that contributes to the mean, growling quality of its sound. There’s also a low-pass filter that’s controlled by a couple of light-dependent resistors, which can be played by blocking them off with a fingertip. A couple of inverters form a drone oscillator that can be switched into the circuit, as well as a 555-based arpeggiator to chop things up a bit.

All those circuits, as well as support for a thirteen-key keyboard, live on one custom PCB. There’s also an off-the-shelf echo/reverb module that’s been significantly hacked to add to the richness of the sound. The custom wood and acrylic case make the whole thing look as good as it sounds.

We noted that [lonesoulsurfer]’s previous “Box of Beezz” drone synth seemed to evoke parts of the “THX Deep Note” at times; similarly, some of the sounds of this synth sound like they’d come from the soundtrack of a [Christopher Nolan] film  — check it out in the video below.

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Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Hexagonal Keyboard

Well, I didn’t mean to take the whole summer off from Keebin’, it just kind of happened that way. You’d think it would have been #13 that tripped me up, but we ain’t even there yet — this is only the twelfth edition. I kept thinking I should write one and it just wasn’t happening, until I got a tip from [s.ol bekic] about their stunning hexagonal keycaps and the journey toward making an open-source 12-key macropad featuring same.

But let’s back up a bit. Originally, [s.ol] designed a totally sick hybrid MIDI-and-typing keyboard from scratch, which you can see in this short video. It glows, it splits in half, and it snaps back together again quite satisfyingly. And you probably noticed the hexagonal keycaps that look like they might be printed or milled, or perhaps even printed and then milled.

In actuality, [s.ol] threw all the processes at this keycap project — milling, molding and casting, and 3D printing. None of them worked well enough to get much past the prototype stage, but in the end, [s.ol] joined forces with fkcaps.com to create and offer an injection-molded version that I’d really, really like to rock my fingertips around in. Good thing I can pick some up for cheap.

Of course, the real process was all the learning [s.ol] did along the way — both in the early days of making the hybrid keyboard, and after teaming up with fkcaps to make the keycaps and the accompanying macropad into real products. And that was after all the design work it took to get this newfangled honeycomb configuration right.

In case you’re wondering, these are meant for only Kailh chocs, but no matter the switch, the spacing is really important because of all the possible points of friction introduced by the design. Be sure to check out the keycap docs page, macropad docs page, and this gallery of keycaps and macropads.

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Billet Machining A Special Xbox

The world of console modding has delivered us some amazing projects over the years, usually rendering an original into a completely different form factor. [Modified] has done a special bit of console modding on an Xbox Series X, with the unusual result of keeping exactly the same form factor. What makes it special? His Series X has been given a new case, almost identical to the original, but instead of molded plastic it’s machined entirely from a single billet of aluminium stock.

From one perspective it’s a slightly crazy endeavor — pushing the limits of his mill to remove 90% of the stock. But from another it’s an interesting tale of how to approach such a project, of the challenges in reaching further into a workpiece than the tooling is designed for, and also of the cooling for the Xbox itself. Sure he could have made it from aluminium plate and screwed it together, but in doing so he’d have denied us the chance to follow a machining adventure.

The result is an Xbox that’s nominally the same as when it left the factory, but which looks so much cooler. Oddly the aluminum doesn’t act as a heatsink because the console is air-cooled, but particularly on the bottom there are more holes than were found in the original. On the front is an engraving of Master Chief from Halo 2‘s cover art which really puts the finishing touch on the build — though we wonder whether it might benefit from a little resin to make it stand out a bit.

Hungry for more Series X case mods? They don’t come bigger than this one!

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A hand holds a round disc of noodles wrapped in a translucent film with herb specs embedded in it.

Reimagined Ramen Comes In Edible Package

Hackers and college students alike reach for ramen when they want to fuel up on a budget, but, if you’re concerned about packaging waste, the plastic film and foil packets start to weigh on your conscience. [Holly Grounds] was sick of this compromise and came up with a way to have your packaging and eat it too.

[Holly] first experimented with different bioplastics until she developed a recipe for “an edible, tasteless starch-based bioplastic, that dissolves in contact with boiling water.” With that accomplished, she next integrated flavoring into the bioplastic wrapper so that there’s no foil packet. She found that herbs and spices worked, but larger solids like shrimp couldn’t be incorporated into the film.

For the finishing touch, she fashioned the noodles into a disk so they fit better in a bowl for cooking. To cook the noodles, you remove a puck from the wax paper sleeve holding multiple servings, add boiling water, stir, and enjoy. [Holly] says that her ramen packets are quicker to prepare than existing packets since there are fewer steps and the shape is optimized for cooking. That’s a win-win for the planet and convenience.

If you want to see another pasta packaging marvel, we’ve previously covered Flat Pack Pasta. Have your own project to reduce packaging waste? Submit it to the Save the World Wildcard round of the Hackaday Prize which closes on October 16th!

Making A Tape Echo The Traditional Way

[Juan Nicola] has taken inspiration from the musician hackers of old and re-purposed a reel-to-reel tape recorder into a tape-echo for his guitar with a built-in valve amplifier (video in Spanish).

The principle is to record the sound of the guitar onto a piece of moving magnetic tape, then to read it back again a short time later.  This signal is mixed with the live input and re-recorded back onto the tape further back.  The effect is heard as an echo, and this approach was very popular before digital effects became readily available.

[Juan] installed a new read-head onto his Grundig TK40 and managed to find a suitable mechanical arrangement to keep it all in place.  He has since updated the project by moving to a tape loop, allowing an infinite play-time by re-using the same piece of tape over and over.

Turning tape machines into echo effects is not a new idea, and we’ve shown a few of them over the years, but every one is slightly different!

Both versions are shown after the break.  YouTube closed-caption auto-translate might come in handy here for non-Spanish speakers.

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Robot: Will Draw For Food

Biological systems often figure out the best ways to get what they need to survive. Now a robot created by researchers at Worcester Polytechnic Institute, Imperial College London, and the University of Illinois Urbana Champaign can make the same claim. The robot operates in front of a plate that has electrical terminals on one end and various obstacles between those terminals and the robot.

The robot can pick up and rearrange some of the items on the plate and then draws paths to the terminals using conductive ink. The effect is the robot gets to “eat” if it solves the connection puzzle.

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