Microcontrollers

2168 Articles

WiFi Status Indicator Keeps Eye On The Network

November 16, 2024 by 19 Comments

These days, most of us take the instant availability of a high-speed link to the Internet for granted. But despite all of the latest technology, things still occasionally go pear-shaped — meaning that blistering fiber optic connection you’ve got to the world’s collected knowledge (not to mention, memes) can still go down when you need it the most.

After suffering some connectivity issues, [Arnov Sharma] decided to put together a little box that could alert everyone in visual range to the status of the local router. It won’t fix the problem, of course, but there’s a certain value to getting timely status updates. Using a 3D printed enclosure and a couple of custom PCBs, the build is fairly comprehensive, and could certainly be pressed into more advanced usage if given the appropriate firmware. If you’ve been thinking of a Internet-connected status indicator, this is certainly a project worth copying studying closely.

Continue reading “WiFi Status Indicator Keeps Eye On The Network” →

RISC-V Pushes 400 Million Forth Words Per Second

November 15, 2024 by 26 Comments

We’ll be honest. Measuring Forth words per second doesn’t seem like a great benchmark since a Forth word could be very simple or quite complex. But we think the real meaning is “up to 400 million words per second.” There was a time when that level of performance would take a huge computer. These days, a simple board that costs a few bucks can do the trick, according to [Peter Forth] in an online presentation.

The key is the use of the Milk V Duo and some similar boards. Some of these look similar to a Raspberry Pi Pico. However, this chip on board has two RISC V cores, an ARM core, and an 8051. There’s also an accelerator coprocessor for vector operations like AI or video applications.

Continue reading “RISC-V Pushes 400 Million Forth Words Per Second” →

Cheap Sensor Changes Personality

November 10, 2024 by 27 Comments

If you want to add humidity and temperature sensors to your home automation sensor, you can — like [Maker’s Fun Duck] did — buy some generic ones for about a buck. For a dollar, you get a little square LCD with sensors and a button. You even get the battery. Can you reprogram the firmware to bend it to your will? As [Duck] shows in the video below, you can.

The device advertises some custom BLE services, but [Duck] didn’t want to use the vendor’s phone app, so he cracked the case open. Inside was a microcontroller with Bluetooth, an LCD driver, a sensor IC, and very little else.

Continue reading “Cheap Sensor Changes Personality” →

DIY Digital Caliper Measures Up

November 8, 2024 by 15 Comments

You might wonder why [Kevin] wanted to build digital calipers when you can buy them for very little these days. But, then again, you are reading Hackaday, so we probably don’t need to explain it.

The motivation, in this case, was to learn to build the same mechanism the commercial ones use for use in precise positioning systems. We were especially happy to see that [Kevin’s] exploration took him to a Hackaday.io project which led to collaboration between him and [Mitko].

Continue reading “DIY Digital Caliper Measures Up” →

Teaching A Pi Pico E-Ink Panel New Tricks

November 8, 2024 by 13 Comments

We’ve noticed that adding electronic paper displays to projects is getting easier. [NerdCave] picked up a 4.2-inch E-ink panel but found its documentation a bit lacking when it came to using the display under MicroPython. Eventually he worked it out, and was kind enough to share with the rest of the class.

These paper-like displays draw little power and can hold static images. There were examples from the vendor of how to draw some simple objects and text, but [NerdCave] wanted to do graphics. There was C code to do it, but it wasn’t clear how to port it to Python.

The key was to use the image2cpp website (we’ve used it before, but you can also use GIMP). Instead of C code, though, you get the raw bytes out and place them in your Python code. Once you know the workflow, it isn’t that hard, and this is an inexpensive way to add a different kind of display to your projects. The same image conversion will help you work with other displays, too.

We aren’t sure what driver chip this particular display uses, but if you have one with the UC8151/IL0373, you can find some amazing MicroPython drivers for those chips.

Continue reading “Teaching A Pi Pico E-Ink Panel New Tricks” →

Hardware-in-the-Loop Continuous Integration

November 6, 2024 by 22 Comments

How can you tell if your software is doing what it’s supposed to? Write some tests and run them every time you change anything. But what if you’re making hardware? [deqing] has your back with the Automatic Hardware Testing rig. And just as you’d expect in the software-only world, you can fire off the system every time you update the firmware in your GitHub.

A Raspberry Pi compiles the firmware in question and flashes the device under test. The cool part is the custom rig that simulates button presses and reads the resulting values out. No actual LEDs are blinked, but the test rig looks for voltages on the appropriate pins, and a test passes when the timing is between 0.95 and 1.05 seconds for the highs and lows. Firing this entire procedure off at every git check-in ensures that all the example code is working.

So far, we can only see how the test rig would work with easily simulated peripherals. If your real application involved speaking to a DAC over I2C, for instance, you’d probably want to integrate that into the test rig, but the principle would be the same.

Are any of you doing this kind of mock-up hardware testing on your projects? Is sounds like it could catch bad mistakes before they got out of the house.

M.2 Makes An Unusual Microcontroller Form Factor

November 3, 2024 by 40 Comments

When we think of an m.2 slot in our laptop or similar, it’s usually in the context of its PCI connectivity for high-speed applications such as solid state disks. It’s a connector that offers much more than that interface though, making it suitable for some unexpected add-ons. As an example [MagicWolfi] has produced an m.2 card which contains the equivalent of a Raspberry Pi Pico.

The board itself has the familiar m.2 edge connector at the bottom, and the RP2040 GPIO lines as postage-stamp indentations round the edges. On the m.2 front is uses the USB interface as well as a UART and the I2C lines, as well as some of the interfaces we’re less familiar with such as ALERT, WAKE, DISABLE1/2, LED 1/2, and VENDOR_DEFINED.

On one level this provides a handy internal microcontroller card with which you can do all the things you’d expect from a Pi Pico, but on another it provides the fascinating possibility of the Pico performing a watchdog or other function for the host device. We would be genuinely interested to hear more about the use of the m.2 slot in this way.

If you’d like to know more about m.2, we’ve taken a look at it in more depth.