It's that festive time of year when goodies arrive from PCBWay, and what a delightful surprise to receive the Partner of the Year award! A huge thanks to PCBWay, my Patreons, and GitHub sponsors for the amazing support. This year has been thrilling, starting with ESP32 projects and diving into nickel plating experiments. I'm particularly excited about the ESP32 Rainbow project, now fully funded and gearing up for a 2025 release. With lots planned for the coming year, here's to a Merry Christmas and an exciting New Year ahead!
To make my ESP32 ZX Spectrum touch keyboard work even better, I needed to ensure every key was independent. The ESP32-S3 only has 14 touch pins, so I’ve been using a matrix approach. While this works well, it struggles with key combinations, critical for the ZX Spectrum. I explored touch detection and experimented with analog multiplexer ICs (4051 series) to expand the touch pins. Initial tests were promising. After prototyping with breadboard-friendly versions and ordering parts, the new keyboard was not only functional but exceeded my expectations. Scanning the keyboard now takes around 20ms, and the solution is ready for...
Hey folks, I revisited my flame lamp project from 2020 and gave it a serious upgrade - we're talking a leap from 300 to a whopping 1024 LEDs thanks to these nifty flexible WS2812 panels. I've kitted it out with a versatile PCB from my Crystal Balls project, tackled power injection challenges and kept things cool with a current-limiting power supply. I had to wrestle with 3D printing and getting the panels to behave inside the lamp's tube, but the end result? A mesmerizing blaze of colors with gorgeous fire effect, all orchestrated by the WLED software. It's like my...
Just upgraded my basic AliExpress crystal balls with some tech wizardry - I've thrown in an ESP32-S3-MINI, a mic, and made them battery powered. Thanks to WLED software, they're now smart and responsive! Shared the KiCAD project for fellow tinkerers. Check out my video to see these balls in action!
Building a USB cable tester turned out to be trickier than anticipated! My first attempt with fully shielded USB sockets was foiled by design flaws and hidden solder issues. The second iteration featured more accessible sockets, yet still posed challenges. The improvement allowed us to distinguish between high-speed cables and average ones. I'm now in the midst of creating Version 3, with all connections broken out for easy testing. Stay tuned for what's next in this unexpectedly complex journey!
In my latest DIY adventure, I explored nickel plating to harden PCBs at home. I was inspired by a slick resistor box design I found through EEVBlog, which had an incredibly cool switching technique but left the PCBs vulnerable to wear from contact scraping. Despite some initial mix-ups and challenges—like dealing with steel instead of pure nickel, using the wrong voltage, and dealing with contamination—my experiments led to some promising results. I even compared the scratch resistance of plated vs. original PCBs in a very informal test. I wrapped up by sharing some handy links for anyone eager to dive...
Disassembling a 16-bit mini handheld video arcade revealed a fairly uncomplex interior with most of the functionality being handled by a blob chip on a single-sided PCB. Despite the simplicity, the impressive design manages to fit 156 games into flash storage on a multi-layered daughter board, which helps simplify the main board's design. While not as hackable as hoped, the teardown provided an interesting glimpse into the device's construction.
In the latest board revision, I've successfully resolved some key issues, including a USB interface conflict between the USB2244 and the ESP32 and a risky battery charging mistake—no more direct USB 5V to the battery! Plus, I managed to wrap this up without any clumsy bodge wiring. I've even introduced a new feature: a microphone is now on board, setting the stage for some exciting future projects. Stay tuned for what's coming!
In this post, I tackle the lack of a DAC on the ESP32-S3 by demonstrating how to use Pulse Density Modulated (PDM) audio with Sigma Delta Modulation to achieve analog audio output. I explore the simplicity of creating a PDM signal and its reconstruction into an audio signal using a low pass filter, even an RC filter, though a more sophisticated active filter is recommended. I guide through using both a timer and the I2S peripheral on the ESP32 for outputting PDM data, noting the quirks and solutions for each method. And I wrap up with how straight PDM signals...
Just received the new PCBs for the ESP32-TV project and they're looking sharp with only a tiny resistor tweak needed. But I discovered a sneaky, undocumented resistor causing a conflict between the ESP32 and USB2244 over the USB connection. Fixed that, but there's a bigger issue lurking in the design - check the schematic in the video and see if you can spot it before I reveal the explosive mistake!
In a thrilling DIY endeavour, I attempted to build the most minimalist ESP32 dev board possible. Diving deep into the schematic of the ESP32 S3 WROOM module, I chopped out the non-essentials and whittled our needs down to bare bones. The experiment saw me juggling USB data lines and voltage regulators, waving goodbye to an array of capacitors and connectors and boldly embracing the simplicity of direct connections. Despite a few hitches, the miniature Frankenboard came alive, proving that sometimes less is more...at least in the world of microcontrollers.
I've been diving deep into the world of PCB (Printed Circuit Board) coils, inspired by Carl Bugeja's incredible PCB motors! After deciding to set up an automated process for creating the coils rather than manually drawing them (can you imagine?), I found our main constraints became track width and spacing, and the number of layers we could use. During the process of creating spirals for our coils, I encountered some interesting problems - spirals are easy, but what about arbitrarily shaped coils? My attempts ultimately lead me to develop more efficient algorithms and KiCad plugins to generate these special coils....