Digital Etch-A-Sketch Also Plays Snake

August 13, 2025 by Lewin Day 2 Comments

The Etch-A-Sketch has been a popular toy for decades. It can be fun to draw on, but you have to get things right the first time, because there’s no undo button. [Tekavou] decided to recreate this popular toy in digital form instead to give it more capabilities.

The build relies on an Inkplate e-paper screen as a display, which is probably as close you can get in appearance to the aluminium dust and glass screen used in an Etch-a-Sketch. The display is hooked up to an ESP32 microcontroller, which is charged with reading inputs from a pair of rotary encoders. In standard drawing mode, it emulates the behavior of an Etch-A-Sketch, with the ESP32 drawing to the e-paper display as the user turns the encoders to move the cursor. However, it has a magical “undo” feature, where pressing the encoder undoes the last movement, allowing you to craft complex creations without having to get every move perfect on your first attempt. As a fun aside, [Tekavou] also included a fun Snake game. More specifically, it’s inspired by NIBBLES.BAS, a demo program included with Microsoft QBasic back in the day.

We’ve seen all kinds of Etch-A-Sketch builds around these parts, including this impressive roboticized version. Video after the break.

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Continuous-Path 3D Printed Case Is Clearly Superior

August 12, 2025 by Lewin Day 9 Comments

[porchlogic] had a problem. The desire was to print a crystal-like case for an ESP32 project, reminiscent of so many glorious game consoles and other transparent hardware of the 1990s. However, with 3D printing the only realistic option on offer, it seemed difficult to achieve a nice visual result. The solution? Custom G-code to produce as nice a print as possible, by having the hot end trace a single continuous path.

The first job was to pick a filament. Transparent PLA didn’t look great, and was easily dented—something [porchlogic] didn’t like given the device was intended to be pocketable. PETG promised better results, but stringing was common and tended to reduce the visual appeal. The solution to avoid stringing would be to stop the hot end lifting away from the print and moving to different areas of the part. Thus, [porchlogic] had to find a way to make the hot end move in a single continuous path—something that isn’t exactly a regular feature of common 3D printing slicer utilities.

The enclosure itself was designed from the ground up to enable this method of printing. Rhino and Grasshopper were used to create the enclosure and generate the custom G-code for an all-continuous print. Or, almost—there is a single hop across the USB port opening, which creates a small blob of plastic that is easy to remove once the print is done, along with strings coming off the start and end points of the print.

Designing an enclosure in this way isn’t easy, per se, but it did net [porchLogic] the results desired. We’ve seen some other neat hacks in this vein before, too, like using innovative non-planar infill techniques to improve the strength of prints.

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Building A 7-Segment Shadow Clock

August 10, 2025 by Lewin Day 6 Comments

There are plenty of conventional timepieces out there in the world; we’ve also featured a great many that are aesthetically beautiful while being unreadably esoteric. This neat “shadow clock” from [Smart Solutions for Home] is not conventional, but it’s still a clock you could use every day.

The display is made of four seven-segment digits, which have a subtle appearance. Each segment uses a solenoid to extend it forward out of the display, or to retract it flush with the faceplate. This creates a numerical display in all one color, with the physical protrusion doing the job of making the numbers visible. This is perhaps where the “shadow clock” name comes from, though you notice the protruding segments moreso than the shadows they cast on the faceplate.

Running the show is an ESP32, paired with H-bridges to drive the solenoids that make up the 7-segment displays. The H-bridges are driven via shift registers to reduce the number of GPIO pins needed. Unlike many other ESP32 clock builds, this one uses a DS3231 real-time clock module to keep accurate time, rather than solely relying on Internet-based NTP time servers. Configuring the clock can be done via a web interface. Design files are available online.

If you think you’ve seen this recently, maybe you’re thinkig of this prototype for a very similar display by [indoorgeek]. And that’s not the only way to make shadow clocks either. After all, the term is not enforced or defined by any global horological organization. Maybe that’s a good thing! Video after the break.

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Custom Bedroom Lighting Controlled By Alexa

August 2, 2025 by Lewin Day 3 Comments

[Arkandas] had a problem. They liked reading in bed, but their bedroom lamps weren’t cutting it—either too bright and direct, or too dim and diffuse. The solution was custom lighting, and a new project began.

The concept was simple—build a custom controller for a set of addressable LED lighting strips that would be installed in the bedroom. Specifically, in the headboard of the bed, providing controllable light directly where it was needed. The strips themselves were installed in aluminum channel with plastic diffusers to give a nice smooth light. [Arkandas] then tasked an ESP32 to control the strips, using the FastLED library to work with WS2812B LEDs, and also the Adafruit NeoPixel library for using SK6812 LEDs and their extra white channel. The ESP32 was set up to provide a web interface for direct control over the local network. [Arkandas] also made good use of the FauxmoESP library to enable the device to be controlled via Amazon Alexa, which fit nicely into their existing smarthome setup. Files are on Github for the curious.

The final build works well, creating a soft light in the habitable area of the bed that can also be readily controlled via voice commands or via web. We’ve seen the ESP32 do other great feats in this arena before, too, albeit of the more colorful variety. Meanwhile, if you’re cooking up your own smart lighting solutions, don’t hesitate to tell the tipsline!

DIY MP3 Player Inspired By The IPod

August 1, 2025 by Lewin Day 6 Comments

These days, the personal MP3 player has been largely replaced by the the smartphone. However, [Justinas Petkauskas] still appreciates the iPod for its tactility and portability, and wanted to bring that vibe back. Enter JPL.mp3

The build is based around the ESP32-S3 microcontroller. It’s hooked up with a PCM5102 DAC hooked up over I2S to provide quality audio, along with a micro SD card interface for music storage, and a small IPS LCD. The best feature, though? The mechanical click-wheel which provides a very tactile way to scroll and interact with the user interface. Everything is assembled into a neat 3D printed case, with a custom four-layer PCB lacing all the electronics together.

On the software side, [Justinas] cooked up some custom software for organizing music on the device using a SQLite database. As he primarily listens to classical music, the software features fields for composer/piece and conductor, orchestra, or performer.

[Justinas] calls the final build “chunky, but nevertheless functional” and notes it is “vaguely reminiscent of classic iPods.” We can definitely see the fun in building your own personalized version of a much-enjoyed commercial product, for sure. Meanwhile, if you’re cooking up your own similar hardware, we’d certainly love to hear about it.

Building A Color Teaching Toy For Tots

July 25, 2025 by Lewin Day No comments

Last year, [Deep Tronix] wished to teach colors to his nephew. Thus, he built a toy to help educate a child about colors by pairing them with sounds, and Color Player was born.

The build is based around the TCS34725, an off-the-shelf color sensor. It’s paired with an ESP32, which senses colors and then plays sounds in turn. [Deep Tronix] made this part harder by insisting on creating their own WAV playback system, using the microcontroller, an SD card, and its on-board digital-to-analog hardware.

The toy operates in three primary modes. Color-to-tone, color-to-sound, color-to-voice. Basically, a color is scanned, and then the Color Player creates a tone, plays back a pre-recorded audio sample, or spells out the name of the color that was just scanned.

[Deep Tronix] also included jolly mode, which just color cycles a few RGB LEDs. However, there’s a game inside jolly mode as well, created for an older nephew to play with. Enter the right button combination, and you unlock it. Then, the device suggests a color and you have to run around, find it, and scan it to score.

We love a good color game; somehow this build seems even more compelling than Milton Bradley’s classic Simon toy.

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2025 One-Hertz Challenge: Pokémon Alarm Clock Tells You It’s Time To Build The Very Best

July 22, 2025 by Adam Zeloof 3 Comments

We’ve all felt the frustration of cheap consumer electronics — especially when they aren’t actually cheap. How many of us have said “Who designed this crap? I could do better with an Arduino!” while resisting the urge to drop that new smart doorbell in the garbage disposal?

It’s an all-too familiar thought, and when it passed through [Mathieu]’s head while he was resetting the time and changing the batteries in his son’s power-hungry Pokémon alarm clock for the umpteenth time, he decided to do something about it.

The only real design requirement, imposed by [Mathieu]’s son, was that the clock’s original shell remained. Everything else, including the the controller and “antique” LCD could go. He ripped out the internals and installed an ESP32, allowing the clock to automatically sync to network time in the event of power loss. The old-school LCD was replaced with a modern, full-color TFT LCD which he scored on AliExpress for a couple of Euros.

Rather than just showing the time, the new display sports some beautiful pixel art by Woostarpixels, which [Mathieu] customized to have day and nighttime versions, even including the correct moon phase. He really packed as much into the ESP32 as possible, using 99.6% of its onboard 4 MB of flash. Code is on GitHub for the curious. All in all, the project is a multidisciplinary work of art, and it looks well-built enough to be enjoyed for years to come.

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