Interactive LED Matrix Is A Great Way To Learn About Motion Controls

January 21, 2025 by Lewin Day 4 Comments

It’s simple enough to wire up an LED matrix and have it display some pre-programmed routines. What can be more fun is when the LEDs are actually interactive in some regard. [Giulio Pons] achieved this with his interactive LED box, which lets you play with the pixels via motion controls.

The build runs of a Wemos D1 mini, which is a devboard based around the ESP8266 microcontroller. [Giulio] hooked this up to a matrix of WS2812B addressable LEDs in two 32×8 panels, creating a total display of 512 RGB LEDs. The LEDs are driven with the aid of an Adafruit graphics library that lets the whole display be addressed via XY coordinates. For interactivity, [Giulio] added a MPU6050 3-axis gyroscope and accelerometer to the build. Meanwhile, power is via 18650 lithium-ion cells, with the classic old 7805 regulator stepping down their output to a safe voltage. Thanks to the motion sensing abilities of the MPU6050, [Giulio] was able to code animations where the LEDs emulate glowing balls rolling around on a plane.

It’s a simple build, but one that taught [Giulio] all kinds of useful skills—from working with microcontrollers to doing the maths for motion controls. There’s a lot you can do with LED matrixes if you put your mind to it, and if you just start experimenting, you’re almost certain to learn something. Video after the break.

Continue reading “Interactive LED Matrix Is A Great Way To Learn About Motion Controls” →

Hydroelectric Generator Gets Power From Siphoning

January 21, 2025 by Bryan Cockfield 42 Comments

Siphons are one of those physics phenomena that, like gyroscopes, non-Newtonian fluids, and electricity, seem almost magical. Thanks to atmospheric pressure, simply filling a tube with liquid and placing the end of the tube below the liquid level of a container allows it to flow against gravity, over a barrier, and down into another container without any extra energy inputs once the siphon is started. They’re not just tricks, though; siphons have practical applications as well, such as in siphon-powered hydroelectric turbine.

This is an iteration of [Beyond the Print]’s efforts to draw useful energy from a local dam with an uneconomic amount of water pressure and/or volume for a typical hydroelectric power station. One of his earlier attempts involved a water wheel but this siphon-based device uses a more efficient impeller design instead, and it also keeps the generator dry as well. Using 3″ PVC piping to channel the siphon, as well as a short length of thinner pipe to attach a shop vac for priming the siphon, water is drawn from the reservoir, up the pipe, and then down through the impeller which spins a small DC generator.

This design is generating about 9 V open-circuit, and we’d assume there’s enough power available to charge a phone or power a small microcontroller device. However, there’s a ton of room for improvement here. The major problem [Beyond the Print] is currently experiencing is getting air into the system and having the siphon broken, which he’s solved temporarily by adding a bucket at the outflow. This slows down the water though, so perhaps with any air leaks mitigated the power generation capabilities will be greatly increased.

Continue reading “Hydroelectric Generator Gets Power From Siphoning” →

Family Bass Is Musical NES Magic

January 21, 2025 by Lewin Day 6 Comments

The Family BASIC keyboard was a peripheral that was built for programming on the Nintendo Family Computer, or Famicom. As [Linus Åkesson] demonstrates, though, it can do so much more. Meet the Family Bass.

The core of the project is a special adapter which [Linus] created to work with the Family BASIC keyboard. Traditionally, the keyboard plugs into the Famicom’s expansion port, but [Linus] wanted to hook it up to the controller port on a Nintendo Entertainment System instead. Getting them to talk was achieved with an ATtiny85 which could cycle through the 72-key matrix in the keyboard and spit out a serial stream of data the controller port could understand.

On the NES end, the console is set up to run custom code from [Linus] that lets him play the internal sound chip’s triangle wave with the keyboard. He demonstrates this ably in a video where he performs a song called Platform Hopping along with some of his other retro computer instruments.

We’ve seen [Linus] build some other great instruments in the past too, which are both creative and nostalgic. Video after the break.

Continue reading “Family Bass Is Musical NES Magic” →

Mining And Refining: The Halogens

January 21, 2025 by Dan Maloney 25 Comments

I was looking at the periodic table of the elements the other day, as one does, when my eye fell upon the right-hand side of the chart. Right next to the noble gases at the extreme edge of the table is a column of elements with similar and interesting properties: the halogens. Almost all of these reactive elements are pretty familiar, especially chlorine, which most of us eat by the gram every day in the form of table salt. As the neighborhoods of the periodic table go, Group 17 is pretty familiar territory.

But for some reason, one member of this group caught my attention: iodine. I realized I had no idea where we get iodine, which led to the realization that apart from chlorine, I really didn’t know where any of the halogens came from. And as usual, that meant I needed to dig in and learn a little bit about the mining and refining of the halogens. At least most of them; as interesting as they may be, we’ll be skipping the naturally occurring but rare and highly radioactive halogen astatine, as well as the synthetic halogen tennessine, which lives just below it in the group.

Continue reading “Mining And Refining: The Halogens” →

Cyber Walkman Does It In Style

January 21, 2025 by Kristina Panos 20 Comments

One of the best things about adulthood is that finally we get to, in most cases, afford ourselves the things that our parents couldn’t (or just didn’t for whatever reason). When [Yakroo108] was a child, Walkmans were expensive gadgets that were out of reach of the family purse. But today, we can approximate these magical music machines ourselves with off-the-shelf hardware.

Besides the cyberpunk aesthetic, the main attraction here is the UNIHIKER Linux board running the show. After that, it’s probably a tie between that giant mystery knob and the super-cool GUI made with Tkinter.

We also like the fact that there are two displays: the smaller one on the SSD1306 OLED handles the less exciting stuff like the volume level and the current time, so that the main UNIHIKER screen can have all the equalizer/cyberpunk fun.

Speaking of, this user-friendly GUI shows play/stop buttons and next buttons, but it looks like there’s no easy way to get to the previous track. To each their own, we suppose. Everything is enclosed in a brick-like 3D-printed enclosure that mimics early Walkmans with orange foam headphones.

If you want an updated Walkman with keyboard switches (who wouldn’t?), check this out.

From Retro To Radiant: 3D Tetris On A LED Matrix

January 21, 2025 by Heidi Ulrich 8 Comments

We love seeing retro games evolve into new, unexpected dimensions. Enter [Markus]’ adaptation of 3D Tetris on a custom-built 3x3x12 RGB LED matrix. Developed as a university project, this open-source setup combines coding, soldering, and 3D printing. It’s powered by an ESP32 microcontroller with gameplay controlled by a neat web interface.

This 3D build makes the classic game so much harder to play, that one could argue whether it’s still a game, or has turned into a form of art. Although it is challenging to rotate and drop blocks on such a small scale, for die-hard Tetris fans (and we know you’re out there), there is always someone up to become best at it. Just look at the FastLED-powered light show, the responsive web-based GUI, and fully modular 3D printed housing, this project is a joy to look at even when nobody is playing it. Heck, a game that turned 40 only a year ago should be so mature to entertain itself, shouldn’t it?

From homemade Pong tables to LED cube displays, hobbyists keep finding ways to give classic games a futuristic twist. Projects like this are about pushing boundaries. Hackaday’s archives are full of similar innovations, but why not craft some new ones?

Continue reading “From Retro To Radiant: 3D Tetris On A LED Matrix” →

A Quarter And A Dime Will Get You A Commodore 64 Softmodem

January 20, 2025 by Lewin Day 43 Comments

Back in the 1980s, a viable modem cost hundreds of dollars. Even in the 1990s, you were looking at spending a a Benjamin or two to get computer squawking down the phone lines. According to [Cameron Kaiser], though, it’s possible to whip up a softmodem using a Commodore 64 for much cheaper than that. How much? Just 35 cents, we’re told!

The inspiration was simple—Rockwell apparently used to build modems using the 6502. The Commodore 64 has a 6502 inside, pretty much, so surely it could be a softmodem, right? Indeed, one [John Iannetta] had done this in a one-way form in the 1980s, using the Commodore 64’s SID audio chip to output data in sound form. In 1998, he espoused the 35-cent modem—basically, the price of buying an RCA jack to hook up a phone line to your Commodore 64.

As [Cameron] found out, the concept still works today, as does [John’s] code, but it’s more like 68 cents in 2025 dollars. With the right bits and pieces, and a little code, you can have your C64 modulating data into sound at rates of 300 baud.

It’s hacky, slow, and there’s no real way to receive—the C64 just doesn’t have the chops to demodulate these kinds of signals on its own. You also shouldn’t use it on a real phone line if you don’t want to damage your C64. Still, it’s a wonderful bit of hackery, and it’s fun to see how well it works. We’ve seen some other great Commodore 64 modem projects before, like the ever-useful RetroModem. Meanwhile, if you’ve got your own communication hacks for the computers of yesteryear, don’t hesitate to let us know!