Microcontrollers

2244 Articles

Cute Brass Lunar Lander Is A Neat Little Environment Monitor

January 19, 2024 by 8 Comments

Sometimes form can make a project more attractive than its simple function. [Mohit Bhoite]’s free-form builds are great examples of this. His latest effort is a gorgeous little device that displays environmental readings, and it’s shaped like a lunar lander. (Nitter) Just exquisite!

The device is based around a Seeedstudio XIAO nRF52840 dev board. It’s hooked up to a BME280 sensor which delivers temperature, humidity and air pressure readings from the immediate environment. These readings are displayed on a tiny 128×32 OLED display, along with the current time. Power is via a compact 14250 lithium cell.

So far, so simple, but the real magic is in the housing. It’s a wireframe lunar lander lookalike which [Mohit] put together using brass wire and some careful soldering. It adds so much to the build, which wouldn’t be nearly as attractive if just assembled on a PCB. It’s not his first rodeo, either. He previously built a cute device (Nitter) with an animated face in 2019 using similar techniques; it used a CCS811 gas sensor to detect air quality.

Often, we find ourselves falling most in love with devices that please the eye. [Mohit] certainly demonstrates a great skill in building things that fit this brief. Sometimes, it only takes a bit of thought and careful application of the mind to bring a beautiful aesthetic to your projects, and the results can be most rewarding. Try his Hackaday Supercon talk if you want to learn more. Continue reading “Cute Brass Lunar Lander Is A Neat Little Environment Monitor” →

Breaking The Flash Encryption Feature Of Espressif’s Microcontrollers

January 15, 2024 by 16 Comments

Espressif’s ESP32 microcontrollers come with a Flash encryption feature that when enabled ensures that the data and code stored on the (usually external) Flash chip is encrypted with AES-256 (ESP32) or better (ESP32-C3, -C6). For the ESP32 this encryption feature has been shown to be vulnerable to side channel attacks (SCA), leading [courk] to not only replicate this result with a custom ESP Correlation Power Analysis (CPA) board (pictured) that captures power usage of the MCU, but also to try his luck with the ESP32-C3 and ESP32-C6 parts that should be tougher nuts to crack.

Whereas the ESP32 uses a fairly straightforward AES-256 encryption routine that together with the exposed Flash communication lines on the QSPI bus make for a textbook SCA example, the ESP32-C3 ups the encryption to XTS-AES, which uses two 128-bit keys on the -C3 part (XTS-256). This particular MCU is still susceptible to the same SCA attack with CPA, making it somewhat harder to attack than the ESP32, but by no means impossible.

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Saving PIC Microcontrollers With DIY Programmer

January 14, 2024 by 32 Comments

When working on a project, plenty of us will reach for an Atmel microcontroller because of the widespread prevalence of the Arduino platform. A few hackers would opt for a bit more modern part like an ESP32. But these Arduino-compatible platforms are far from the only microcontrollers available. The flash-based PIC family of microcontrollers is another popular choice. Since they aren’t quite as beginner or user-friendly, setting up a programmer for them is not as straightforward. [Tahmid] needed to program some old PIC microcontrollers and found the Pi Pico to be an ideal programmer.

The reason for reaching for the Pico in the first place was that [Tahmid] had rediscovered these decade-old microcontrollers in a parts bin but couldn’t find the original programmer. Thanks to advances in technology in the last ten years, including the advent of micropython, the Pico turned out to be the ideal programmer. Micropython also enables a fairly simple drag-and-drop way of sending the .hex file to the PIC, so the only thing the software has to do is detect the PIC, erase it, and flash the .hex file. The only physical limitation is that the voltages needed for the PIC are much higher than the Pico can offer, but this problem is easily solved with a boost converter (controlled by the Pico) and a level shifter.

[Tahmid] notes that there’s plenty of room for speed and performance optimization, since this project optimized development time instead. He also notes that since the software side is relatively simple, it could be used for other microcontrollers as well. To this end, he made the code available on his GitHub page. Even if you’re more familiar with the Arduino platform, though, there’s more than one way to program a microcontroller like this project which uses the Scratch language to program an ESP32.

Building A Loop Station With An RP2040

January 11, 2024 by 9 Comments

Loop stations are neat things, able to replay one or more loops of audio over and over again while you perform over the top of them. Musicians like [Marc Rebillet], [Reinhardt Buhr], and [Dub FX] have made careers out of this style of performance. [Yaqi Gao], [Xiaoyu Liang] and [Alina Wang] decided to build a loop station of their own, using the popular RP2040 chip.

At its simplest, a loop station must take in audio, record it, and then play it back. Generally, it can do this with several tracks and mix them together, while also mixing in the incoming audio as well. The group achieved this by inputting a guitar signal to the chip via an amplifier and the onboard analog-to-digital converter. The audio can be recorded as desired, and then played back via an external digital-to-analog converter. Live audio from the guitar is also passed through to allow performing over the recorded sound. The group also used an external half-megabyte FRAM chip to allow storing additional audio sample data, which can be trucked out over serial and saved.

It’s not the cleanest loop station in the world, with a relatively low sample rate causing some artifacts. Regardless, it definitely works, and taught the group plenty about working with digital audio in the process. For that reason alone, we’d call it a success.

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A Very 21st Century Receiver For A Very 20th Century Band

January 9, 2024 by 24 Comments

The FM broadcast band has been with us since the middle of the 20th century, and despite many tries to unseat it, remains a decent quality way to pick up your local stations. It used to be that building an FM broadcast receiver required a bit of RF know-how, but the arrival of all-in-one receiver chips has made that part a simple enough case of including a part. That’s not to say that building a good quality FM broadcast receiver in 2024 doesn’t involve some kind of challenge though, and it’s one that [Stefan Wagner] has risen to admirably with his little unit.

Doing the RF part is an RDA5807MP single chip radio, but we’d say the center of this is the CH32V003 RISC-V microcontroller and its software. Twiddling the dial is a thing of the past, with a color display and all the computerized features you’d expect. Rounding it off in the 3D printed case is a small speaker and a Li-Po pouch cell with associated circuitry. This really is the equal of any commercially produced portable radio, and better than many.

Even with the all-in-one chips, there’s still fun in experimenting with FM the old way.

A Picture Frame For Your Eyes Only

January 8, 2024 by 2 Comments

We can think of all kinds of reasons you’d want to display a picture that only you and the family can see, and we don’t even have to work blue to do it. Whether as a joke, or as a serious way to hide a special image, this magical picture frame by [Placitech] is just the thing.

You might recognize this as using PDLC switchable “smart” film. Whenever power is applied, the panel goes from frosty opacity to near-crystal clarity in an instant. The trick here is to to image recognition and only allow certain faces to unlock the picture.

The brains of this operation is an ESP32-CAM module, which does all the heavy lifting of getting the image in the first place, handling it, and deciding via code who is eligible to flick the switch. Everything is housed in a nice 3D printed frame that [Placitech] designed.

Be sure to check out the build video after the break, and files are available via [Placitech]’s Discord if you’d like to build this yourself.

There’s a lot you can do with PDLC panels, as evidenced by this amazing dress.

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1D Fireworks Are Nice And Quiet

January 6, 2024 by 17 Comments

Maybe you do it out of respect for the dogs and parents of young children in the neighborhood. Or maybe you do it because they’re harmful to the environment, or just because it’s too darn cold outside. Whatever your reasoning for not setting off fireworks, don’t fret — you can probably put together your own silent one-dimensional “fireworks” display from what you’ve got in the parts bin.

[Daniel Westhof]’s design is simple, requiring little more than a Wemos D1 Mini and a strip of WS2812 LEDs. Once activated, a red rocket shoots up from the ground and detonates, sending lights in both directions on the strip to imitate the bombs bursting in air. It’s controlled with a small push button switch, and there’s a deliciously large red LED indicator that shows the thing is ready for detonation.

You might be surprised to find that there’s a wide array of 1D gaming and animation projects out there, many of which made possible by the ubiquitous addressable RGB LED strip. We’ve seen a dungeon crawler, at least two different versions of the classic PONG, and even the makings of a simplified Wolfenstein.