Parts

678 Articles

An ASIC For A Secret File

March 24, 2024 by 6 Comments

Some time over a decade ago, the arrival of inexpensive PCB fabrication revolutionised the creation of custom electronics on a budget. It’s now normal for even the smallest projects we feature here to have a professional PCB, which for those of us who started by etching their own with ferric chloride is nothing short of a miracle. When it comes to the ultimate step in custom electronics of doing the same for integrated circuits though, it’s fair to say that this particular art is in its infancy. The TinyTapeout project is a collaborative effort in which multiple designers have the chance to make their own ASIC as a single tile on a chip along others, and [Bitluni] had the chance to participate. His ASIC? A secret file which could be read through his ESP32 to VGA board.

The video below the break then is both the tale of the secret file project, and that of TinyTapeout itself, which is a clever design involving an on-board microcontroller that selects the tile and manages the bus. This revision is Tiny Tapeout 3, which includes 249 tiles of contributor-generated circuitry holding a diverse array of projects.

The secret file itself is a motion GIF, compressed down until the point at which it will just fit on a tile. We’ll preserve the fun by not reveling what it us, but you probably won’t be surprised when you see it in the video.

We’ve featured TinyTapeout more then once, not least when [Matt Venn] gave a talk about it for Supercon 2022.

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Magnetic Power Cable Makes Mobility Scooter Much Better

March 21, 2024 by 10 Comments

Sometimes, you have to wonder what major manufacturers of assistive tech are thinking when they design their products. [Niklas Frost]’s father has MS and uses an electric mobility scooter to get around. It’s a good solution to a terrible problem, except it stops short of the most important part — the charging scheme. Because of the aforementioned mobility issues, [Niklas]’s father can’t plug and unplug it without assistance. So much for independence.

And so [Niklas] gave it some thought and came up with an incredibly easy way that Dad can charge his scooter. It’s even non-intrusive — all it took was a handful of off-the-shelf components and some 3D printed parts to make what’s essentially an extension cord between the charger and the scooter. Really, there’s nothing more to it than three 10 A magnetic connectors, an XLR female port, an XLR male connector, and some very helpful plastic.

Something interesting to note: [Niklas] spent a year or so tinkering with a robot that could drive the plug over to the charger and plug it in. A book on the subject made him destroy that robot, however, when he realized that he was being driven more by cool technologies than solving the problem at hand. Within a few days of changing course, [Niklas]’ dad was charging his own scooter.

Now, if [Niklas] wants to see about making the scooter move a whole lot faster, we have just the thing.

Unusual Port Combines DisplayPort And HDMI

March 12, 2024 by 22 Comments

Everyone knows you can’t plug an HDMI cable into a DisplayPort… port, and yet a recent video from [Jon Bringus] challenges that seemingly obvious assumption. The hardware in question is a variant of the 2013-era Xi3 X7A mini PC, code-named ‘Piston’ and also known as a ‘Steambox’, from back when that was still something that Valve was working on. Although the physical format here is definitely quaint, it might be implementing DisplayPort Dual-Mode (DP++), which was introduced around the same time.

With DP++ the DP port can detect when a DVI or HDMI adapter is connected and then transmit DVI/HDMI TMDS signals rather than DP signals. Since DP and HDMI/DVI use a different signaling scheme, normally an active adapter would be required. One disadvantage of DP++ is that the HDMI signal will be limited to e.g. 1920×1080 @ 120 Hz and 4K only at 30 Hz.

Normally a DP++ port is marked as such, and requires an adapter that works with the DP++ port. What Xi3 did in this case to make regular DP and HDMI connectors work seems to be somewhat of a mystery, with any information on this type of port being rather scarce. [Jon] thinks he may have found the part itself listed on Mouser, but isn’t completely sure.

Feel free to leave your thoughts and any information you have on this oddity in the comments.

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That’s A Lot Of Building Systems

March 8, 2024 by 9 Comments

The only thing makers like more than building things is making systems to build things. [Eric Hunting] has compiled a list of these modular building systems.

You’ve certainly heard of LEGO, grid beam, and 80/20, but what about Troxes or Clickaloo? The 70 page document has a helpful index at the beginning arranged in families of similar systems followed by information about each and some helpful links.

As the well-known XKCD comic likes to point out, the issue with standards is that they tend to proliferate instead of getting adopted, so this might be a good list to check before you start to implement your brilliant spin on modular construction. It’s possible the right system is already waiting for you.

The list certainly isn’t exhaustive, but it’s a good place to start. If you do have the modular building system that will solve all the world’s problems though, by all means, send it to the tipsline!

What’s A Transfluxor?

March 3, 2024 by 11 Comments

In the 1967 movie The Graduate, a wise older man gives some advice to the title character: plastics. Indeed, plastics would become big business. In 1962, though, a computer-savvy character might have offered a different word: transfluxor. What’s a transfluxor? Well, according to computer history sleuth [Ken Shirriff], it was the heart of a 20-pound transistor computer from Arma. Of course, plastics turned out to be a better bet, but in 1962, the transfluxor seemed to be the wave of the future.

In 1962, most computers were room-sized, but the Arma was “micro” taking up just 0.4 cubic feet — less than an Apple II. It would eventually spawn computers used in ships at sea and airplanes ranging from the Concorde to Air Force One.

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Washing Machine Motors Unlocked

February 29, 2024 by 19 Comments

There’s great potential in salvaging a motor from a broken appliance, but so often the part in question is very specific to its application, presenting a puzzle of wires to the experimenter. This was very much the case with older washing machines and other white goods, and while their modern equivalents may have switched to more understandable motors, there are still plenty of the older ones to be had. [Matthias random stuff] sheds a bit of light on how these motors worked, by means of a 1980s Maytag washing machine motor.

Many of us will be used to old-style induction motors, in which two windings were fed out of phase via a large capacitor. This one doesn’t have a capacitor, instead it has a primary winding and a secondary one with a higher resistance. We’re not quite sure the explanation of the resistance contributing to a phase shift holds water, however this winding is connected in for a short time at start-up by a centrifugal switch. Even better, reversing its polarity reverses the direction of the motor.

The result is a mess of wires demystified, and a mains powered motor with a bit of strength for your projects. We’ve let a few of these motors slip through our fingers in the past, perhaps we shouldn’t have been so hasty.

This is a subject that we’ve looked at in the past.

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The Photodiode You Never Knew You Had

February 28, 2024 by 34 Comments

Optoelectronics hold a range of possibilities for the hardware experimenter — indeed who among us hasn’t added LEDs aplenty to our work? What many of us may be unaware of though is that an LED is also a photodiode, and can even be persuaded to generate usable quantities of power. [Voltative] takes a look at this phenomenon with a series of experiments.

Lighting up an LED from a set of other LEDs is pretty cool, as is powering a calculator, or even the calculator powering itself from its on-board LED. But what caught our eye was using two LEDs as a data link, with both of them acting as transmitter and receiver (something on searching we find we’ve seen before). The possibilities there become interesting indeed.

Given that we are now surrounded by LEDs, from OLED screens to LED lighting, we can’t help wondering what the photodiode performance of some other types of part might be. Would the large area of a lighting LED give a better result for example, or would the phosphorescent coating of a white LED make it useless. We feel there’s more scope for experimentation here.

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