Tales From The Global Chip Shortage: Smoothieboard

July 17, 2021 by Stephen Ogier 27 Comments

The semiconductor shortage sparked by the pandemic is showing no signs of slowing down. Although auto manufacturers were some of the first affected, the shortage has now spread and is impacting all sorts of projects, including the Smoothieboard open-source CNC controllers.

[Chris Cecil] walks through the production woes they’ve had over the last few months. It began this spring with a batch of the V1.1 boards. The prices of some of their chips started jumping, and then they were informed that the microcontroller that serves as the brains of the Smoothieboard was only available for five times the old price. In the end, they placed a smaller order, and V1.1 Smoothieboards will likely be scarce until the microcontroller’s price returns to normal.

Getting V2 of the boards into production has been even more difficult. Just weeks before the final prototype, it was discovered that the LPC4330 microcontroller the V2 was built around was also sold out worldwide. With the shortage in mind, a hole was left in the layout of the final version of V2 so that they could finish the design around whatever microcontroller they were able to get. In the end, they were able to lock down a supply of STM32H745 controllers, which are actually substantially more capable than the original device.

If you’re interested in the origins of the chip shortage, this article from January is a good place to start. This isn’t the first time parts shortages have wreaked havoc on the world of electronics—does anyone remember the global resistor shortage of ’18?

Open Source Is Choice

July 17, 2021 by Elliot Williams 79 Comments

If you haven’t been following along with the licensing kerfuffle surrounding the open-source Audacity audio editing software, take a sec to read Tom Nardi’s piece and get up to speed. The short version is that a for-profit company has bought the trademark and the software, has announced plans to introduce telemetry where there was none, made ominous changes to the privacy policy that preclude people under the age of consent from using the software, and requested that all previous developers acquiesce to a change in the open-source license under which it is published. All the while, the company, Muse, says that it will keep the software open, and has walked back and forth on the telemetry issue.

What will happen to “Audacity”? Who knows. But also, who cares? At least one fork of the codebase has been made, with the telemetry removed and the old open licenses in place. The nicest thing about open source is that I don’t care one bit if my software is named Audacity or Tenacity, and this is software I use every week for production of our podcast. But because I haven’t paid any license fees, it costs me absolutely nothing to download the same software, minus some anti-features, under a different name. If the development community moves over to Tenacity, it’ll all be fine.

Tom thinks that the Audacity brand is too big to fail, and that Muse will have a hit on their hands. Especially if they start implementing new, must-have features, they could justify whatever plans they have in store, even if they’re only available as a “freemium” Audacity Pro, with telemetry, under a more restrictive license. When that does happen, I’ll have to make the choice between those features and the costs, but I won’t be left out in the cold as long as the Tenacity fork gets enough eyes on it. So that’s just more choice for the end-user, right? That’s cool.

Compare this with closed source software. There, when the owner makes an unpopular decision, you simply have to take it or make the leap to an entirely different software package. This can be costly if you’ve gotten good at using that software, and between licenses and learning, there’s a lot of disincentive to switching. Not so in this case. If I don’t want to be tracked while editing audio offline, I don’t have to be. Woot.

The elephant in the room is of course the development and debugging community, and it’s way too early to be making predictions there. However, the same rules apply for devs and users: switching between two virtually identical codebases is as easy as git remote add origin or apt get install tenacity. (Unpaid) developers are free to choose among forks because they like the terms and conditions, because one group of people is more pleasant to work with, or because they like the color of one logo more than the other. Users are just as free to choose.

Time will tell if Audacity ends up like the zombie OpenOffice, which is downloaded in spite of the much superior LibreOffice just because of the former’s name recognition. I know this split riles some people up, especially in the LibreOffice development community, and it does seem unfair that the better software somehow enjoys less reputation. But for those of us in the know, it’s just more choice. And that’s good, right?

Soviet Scientific Calculator Gives Up Its Cold War-Era Secrets

July 17, 2021 by Dan Maloney 17 Comments

Say what you want about Soviet technology, but you’ve got to admit there was a certain style to Cold War-era electronics. Things were perhaps not as streamlined and sleek as their Western equivalents, but then again, just look at the Nixie tube craze to see where collectors and enthusiasts stand on that comparison.

One particularly interesting artifact from the later part of that era was the lovely Elektronika MK-52 “microcalculator”. [Paul Hoets] has done a careful but thorough teardown of a fine example of this late-80s machine. The programmable calculator was obviously geared toward scientific and engineering users, but [Paul] relates how later versions of it were also used by the financial community to root out banking fraud and even had built-in cryptographic functions, which made encrypting text easy.

[Paul] has put together a video of the teardown, detailing the mostly through-hole construction and the interesting use of a daughter-board, which appears to hold the high-voltage section needed to drive the 11-character VFD tube. The calculator appears to be very well cared for, and once reassembled looks like it would be up for another ride on a Soyuz, where once it served as a backup for landing calculations.

We love the look of this machine and appreciate [Paul]’s teardown and analysis. But you say that the Cyrillic keyboard has you stumped and you need a bilingual version of the MK-52? That’s not a problem.

Finding Fractals In The 1930’s

July 17, 2021 by Matthew Carlson 22 Comments

The mesmerizing properties of fractals are surprising as their visual complexity often arises from simple equations. [CodeParade] set out to show how simple a fractal is by creating them using technology from the 1930s. The basic idea is based on projectors and cameras, which were both readily available and widely used in television (CRT projectors were in theaters by 1938, though they weren’t in color until the 1950s).

By projecting two overlapping images on the wall, pointing a camera at the resulting image, and then feeding it back into the projectors, you get some beautiful fractals. [CodeParade] doesn’t have a projector, much less two. So he did what any hacker might do and came up with a clever workaround. He made a simple app that “projects” onto his monitor and all he has to do is point an external webcam at the screen. The resulting analog fractals are quite beautiful and tactile. Rather than tweaking a variable and recompiling, you simply just add a finger or move the camera to introduce new noise that quickly becomes signal.

Better yet, there’s a web version that you can play around with right now. For more fractals implemented in hardware rather than software, there’s this FPGA with a VHDL Mandelbrot set we covered.

Continue reading “Finding Fractals In The 1930’s” →

Fixing Joy-Con Drift With Recycle Bin Parts

July 16, 2021 by Kristina Panos 16 Comments

Have you seen this yet? YouTuber [VK’s Channel] claims to have a permanent fix for Joy-Con drift — the tendency for Nintendo Switch controllers to behave as though they’re being moved around when they’re not even being touched. Like everyone else, [VK’s Channel] tried all the usual suspects: compressed air, isopropyl alcohol, contact cleaner, and even WD-40. But these are only temporary fixes, and the drift always comes back. None of the other fixes so far are permanent, either, like shimming the flat cable that connects the stick to the mobo, adding graphite to the worn pads inside, or trying to fix a possible bad antenna connection.

While calibrating a drifting Joy-Con, [VK’s Channel] noticed that applying pressure near the Y and B buttons corrected the issue immediately, so they got the idea to add a 1mm thick piece of card stock inside. [VK’s Channel] believes the issue is that there is no fastener connecting the plastic part of the joystick to the metal part on the bottom. Over time, using the joystick causes the bottom to sag, which makes the metal contacts inside lose their grip on the graphite pads. It’s been two months now and there is absolutely no drift in either of the Joy-Cons that [VK’s Channel] has shored up this way.

Nintendo is now fixing Joy-Cons for free. The problem is that they are replacing irreparable ones outright, so you have to agree that you will settle for a plain old gray, red, or blue instead of your special edition Zelda controllers or whatever you send them. Hopefully, this really is a permanent fix, and that Nintendo gives [VK’s Channel] a job.

You could forego the joysticks altogether and swap them out for touchpads. Suffering from XBOX drift instead? We have just the thing.

Continue reading “Fixing Joy-Con Drift With Recycle Bin Parts” →

Interpreters In Scala

July 16, 2021 by Al Williams 15 Comments

You might think of interpreters as only good for writing programs. Many people learned programming on some kind of interpreter — like BASIC — because you get immediate feedback and don’t have to deal with the complexities of a compiler. But interpreters can have other uses like parsing configuration files, for example. [Sakib] has a very complete tutorial about writing an interpreter in Scala, but even if you use another language, you might find the tutorial useful.

We were impressed because the tutorial uses formal parsing using a lexer and a parser. This is how you’d be taught to do it in a computer science class, but not how everyone does it.

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A Cheap Dipole Antenna From An Extension Cord

July 16, 2021 by Al Williams 12 Comments

Dipoles are a classic builder’s antenna, after all they are usually little more than two pieces of wire and a feedline. But as [Rob] shows us in the video below, there are a few things to consider.

The first thing is where to get the wire. A damaged extension cord donated the wire. That’s actually an interesting idea because you get multiple wires the same length inside the extension cord. Continue reading “A Cheap Dipole Antenna From An Extension Cord” →