Modular Magnetic LED Matrix

[bitluni] seems rather fond of soldering lots of LEDs, and fortunately for us the result is always interesting eye candy. The latest iteration of this venture features 8 mm WS2812D-F8 addressable LEDs, offering a significant simplification in electronics and the potential for much brighter displays.

The previous version used off-the-shelf 8×8 LED panels but had to be multiplexed, limiting brightness, and required a more complex driver circuit. To control the panel, [bitluni] used the ATtiny running the MegaTinyCore Arduino core. Off-the-shelf four-pin magnetic connectors allow the panels to snap together. They work well but are comically difficult to solder since they keep grabbing the soldering iron. [bitluni] also created a simple battery module and 3D printed neat enclosures for everything.

Having faced the arduous task of fixing individual LEDs on massive LED walls in the past, [bitluni] experimented with staggered holes that allow through-hole LEDs to be plugged in without soldering. Unfortunately, with long leads protruding from the back of the PCB, shorting became an immediate issue. While he ultimately resorted to soldering them for reliability, we’re intrigued by the potential of refining this pluggable design.

The final product snapped together satisfyingly, and [bitluni] programmed a simple animation scheme that automatically updates as panels are added or removed. What would you use these for? Let us know in the comments below. Continue reading “Modular Magnetic LED Matrix”

Is That A Coaster? No, It’s An LED Matrix!

I’m sure you all love to see some colorful blinkenlights every now and then, and we are of course no exception. While these might look like coasters at a distance, do not be deceived! They’re actually [bitluni]’s latest project!

[bitluni]’s high-fidelity LED matrix started life as some 8×8 LED matrices lying on the shelf for 10 years taunting him – admit it, we’re all guilty of this – before he finally decided to make something with them. That idea took the form of a tileable display with the help of some magnets and pogo pins, which is certainly a very satisfying way to connect these oddly futuristic blinky coasters together.

It all starts with some schematics and a PCB. Because the CH32V208 has an annoying package to solder, [bitluni] opted to have the PCB fab do placement for him. Unfortunately, though, and like any good prototype, it needed a bodge! [bitluni] had accidentally mirrored a chip in the schematic, meaning he had to solder one of the SMD chips on upside-down, “dead bug mode”. Fortunately, the rest was seemingly more successful, because with a little 3D-printed case and some fancy programming, the tiny tiles came to life in all of their rainbow-barfing glory. Sure, the pogo pins were less reliable than desired, but [bitluni] has some ideas for a future version we’re very much looking forward to.

Video after the break.
Continue reading “Is That A Coaster? No, It’s An LED Matrix!”

Nice Retro Displays Set This Watch On Edge

A common design language for watches has evolved ever since they first started popping up in the 1500s. Whether worn on the wrist or in a pocket, watches are relatively slim front to back, with the display mounted on the face. That’s understandable given the imperatives of human anatomy. Still, it’s not the only way to arrange things, as this very cool LED matrix watch with an edge-mounted display demonstrates.

True, the unique form factor of this watch wasn’t really the point of the whole project. Rather, [Vitali]’s design was driven by a couple of things. First off were the extremely cool Hewlett Packard HDSP-2000 displays, with four 5×5 5×7 LED matrices shining through the clear cover of a DIP-12 package. Also visible through the cover are the shift registers that drive the matrices, complete with gold bonding wires.

The main attraction for [Vitali], though, was the challenge of working within the limits of the ATtiny85 he chose to run the watch. The MCU’s limited IO made hardware multiplexing necessary, no mean feat given the limited resources and real estate available. He still managed to pack everything in, with the unique edge-mount display coming from the LEDs bridging the space between the two main PCBs. Everything fits into a nice wood veneer case, although we think it looks just fine without it. [Vitali] puts it through its paces in the short video below.

Hats off to [Vitali] for a great-looking project that pushed his limits. We just love these displays, too; of course, it’s not the first time we’ve seen them put to similar use.

Continue reading “Nice Retro Displays Set This Watch On Edge”

An Animated LED Fireplace Powered By The CH32V003

Once you’ve mastered the near-magical ability of turning your ideas into a piece of hardware you can hold in your hand, it’s only natural that you’ll want to spread the joy. The holidays are a perfect time to produce a custom piece of electronics for friends and family, but there’s a catch: going from making one or two of something to making dozens of them can introduce some interesting challenges. Not only will you want to cost optimize your design, but to save yourself some aggravation, you’ll likely want to simplify the assembly process.

The fifty electronic fireplaces designed by built by [Adam Anderson], [Daniel Quach], and [Johan Wheeler] are a perfect example of both concepts, and while we’re coming across it a bit late for this year’s gift exchange, we wouldn’t be surprised if these MIT-licensed beauties end up under a few more trees in 2024.

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BBC Micro:Bit As Handheld Synthesizer

The BBC Micro:bit, while not quite as popular in our community as other microcontroller development boards, has a few quirks that can make it a much more interesting piece of hardware to build a project around than an Arduino. [Turi] took note of these unique features and decided that it was the perfect platform to build a synthesizer on.

The Micro:bit includes two important elements that make this project work: the LED matrix and a gyro sensor. [Turi] built a 5×5 button matrix for inputs and paired each to one of the diodes, which eliminates the problem of false inputs. The gyro sensor is used for detuning, which varies the pitch of any generated sound by a set amount according to the orientation of the device. It also includes a passive low-pass filter to make the sound more pleasant to the ear, especially for younger players of the machine. He’s released the source code on his GitHub page for anyone interested in recreating it.

While this was a one-off project for [Turi], he notes that using MicroPython to program it instead of C led to a lot of unnecessary complications, and the greater control allowed by C would enable some extra features with less hassle. Still, it’s a fun project that really showcases the unique features of this board, much like this tiny Sumo robot we covered over the summer.

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Digital Light Pipes Clock various view of seven-segment display using illuminated light-pipes

LED Clock Has Its Pipes On Display

For most hackers and makers, building a clock is a rite of passage. Few, though, will be as unusual and engaging as this design by [TerraG2].

By combining addressable LEDs, light pipes and 7-segment displays, [TerraG2] has built a timepiece that looks great and will surely be a great conversation starter as well. It’s packed full of features such as automatic brightness control, an accelerometer controlled user interface, and WiFi to make sure it’s always accurate.

partial rear view of the clock showing illuminated light pipes
Partial rear view of the clock showing illuminated light pipes

The decision to leave the light pipes visible behind the main display really makes the project stand out from other clock builds, and the methods [TerraG2] has used to achieve this look will no doubt be transferable to a host of other projects.

The LEDs are courtesy of a standard 8×8 RGB matrix, with a custom 3D-printed shroud to hold the light pipes in place and a clever connector at the other end to illuminate the segments. With two LEDs per segment, seven segments per digit, and four digits, there’s even room for some extra features down the line if you can think of a use for those eight spare LEDs.

The brain of the project is an ESP8266 D1 with an MPU6050 inertial measurement unit (IMU) to detect when it’s flipped over to change the color scheme.

Full documentation is on Github, and a video of the clock in use is after the break.

Light pipes have been used to great effect in some other clock projects we’ve seen, such as this modern Nixie clock and this “clock of clocks”, as well as in this light organ that we showed recently.

Continue reading “LED Clock Has Its Pipes On Display”

A clock displaying a micro QR code

LED Clock Uses Micro QR Codes To Show The Time

As you probably know, we love our clocks here at Hackaday. Odd display technologies are always interesting to see, as are unusual encoding techniques such as binary, ternary or higher-radix number systems. Still, clocks are typically meant to be human-readable, even if their encoding might be a little eccentric.

[Kitchi] however built an LED-based clock that is not human-readable, at least not without quite a bit of training. This is because it displays the time by generating a QR code, which only becomes readable to most humans through the use of a smartphone app. Of course, this negates the need for a clock since your smartphone will already have one anyway — but whoever said a clock needs to be useful?

To be fair, the display could conceivably be read by a determined human, since the QR format used is the tiny Micro QR M2 version that measures only 13×13 pixels. It’s capable of storing ten decimal digits, just enough to hold the date and time in mmddhhmmss format. The fixed part of the QR code is made of paper, while the variable part is formed through a grid of 90 white LEDs. The LEDs are mounted on a piece of prototype board along with a PIC 16F1504 microcontroller, two TM1637 LED drivers and a DS1307 real-time clock with battery backup.

If decoding QR codes is not your thing, or you simply haven’t got your smartphone on you, then the QR clock can also be set to a more human-readable format by adding a jumper. The time will then scroll across the LED screen in ordinary decimal format.

The video in the link is in Japanese, with no automatic translation available, but the build process is clearly shown and should be understandable even if you can’t follow the cheerful robotic narrator. We’ve seen a couple of QR-code based clocks before, some with an LCD screen and some with retro styling, but all of those use the larger standard QR code which definitely no human can decode visually. Or can you? Let us know in the comments!

Thanks for the tip, [J. Peterson]!