Git Your PCBs Online

October 6, 2022 by Arya Voronova 16 Comments

Last time, I’ve shown you how to create a local Git repository around your PCB project. That alone provides you with local backups, helping you never lose the changes you make to your files, and always be able to review the history of your project as it developed.

However, an even more significant part of Git’s usefulness is the ability to upload our creations to one of the various online Git repository hosting services, and keep it up to date at all times with a single shell command. I’d like to show you how to upload your project to GitHub and GitLab, in particular!

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Lithium-Ion Batteries Are Easy To Find

October 3, 2022 by Arya Voronova 43 Comments

In the first article, I’ve given you an overview of Lithium-Ion batteries and cells as building blocks for our projects, and described how hackers should treat their Lithium-Ion cells. But what if you don’t have any LiIon cells yet? Where do you get LiIon cells for your project?

Taking laptop batteries apart, whether the regular 18650 or the modern pouch cell-based ones, remains a good avenue – many hackers take this road and the topic is extensively covered by a number of people. However, a 18650 cell might not fit your project size-wise, and thin batteries haven’t quite flooded the market yet. Let’s see what your options are beyond laptops. Continue reading “Lithium-Ion Batteries Are Easy To Find” →

Books You Should Read: The Hardware Hacker’s Handbook

August 5, 2022 by Arya Voronova 37 Comments

Here on Hackaday, we routinely cover wonderful informative writeups on different areas of hardware hacking, and we even have our own university with courses that delve into topics one by one. I’ve had my own fair share of materials I’ve learned theory and practical aspects from over the years I’ve been hacking – as it stands, for over thirteen years. When such materials weren’t available on any particular topic, I’d go through hundreds of forum pages trawling for details on a specific topic, or spend hours fighting with an intricacy that everyone else considered obvious.

Today, I’d like to highlight one of the most complete introductions to hardware hacking I’ve seen so far – from overall principles to technical details, spanning all levels of complexity, uniting theory and practice. This is The Hardware Hacking Handbook, by Jasper van Woudenberg and Colin O’Flynn. Across four hundred pages, you will find as complete of an introduction to subverting hardware as there is. None of the nuances are considered to be self-evident; instead, this book works to fill any gaps you might have, finding words to explain every relevant concept on levels from high to low.

Apart from the overall hardware hacking principles and examples, this book focuses on the areas of fault injection and power analysis – underappreciated areas of hardware security that you’d stand to learn, given that these two practices give you superpowers when it comes to taking control of hardware. It makes sense, since these areas are the focus of [Colin]’s and [Jasper]’s research, and they’re able to provide you something you wouldn’t learn elsewhere. You’d do well with a ChipWhisperer in hand if you wanted to repeat some of the things this book shows, but it’s not a requirement. For a start, the book’s theory of hardware hacking is something you would benefit from either way. Continue reading “Books You Should Read: The Hardware Hacker’s Handbook” →

Natural Language AI In Your Next Project? It’s Easier Than You Think

May 18, 2022 by Donald Papp 25 Comments

Want your next project to trash talk? Dynamically rewrite boring log messages as sci-fi technobabble? Happily (or grudgingly) answer questions? Doing that sort of thing and more can be done with OpenAI’s GPT-3, a natural language prediction model with an API that is probably a lot easier to use than you might think.

In fact, if you have basic Python coding skills, or even just the ability to craft a curl statement, you have just about everything you need to add this ability to your next project. It’s not free in the long run, although initial use is free on signup, but for personal projects the costs will be very small.

Basic Concepts

OpenAI has an API that provides access to GPT-3, a machine learning model with the ability to perform just about any task that involves understanding or generating natural-sounding language.

OpenAI provides some excellent documentation as well as a web tool through which one can experiment interactively. First, however, one must create an account and receive an API key. After that is done, the doors are open.

Creating an account also gives one a number of free credits that can be used to experiment with ideas. Once the free trial is used up or expires, using the API will cost money. How much? Not a lot, frankly. Everything sent to (and received from) the API is broken into tokens, and pricing is from $0.0008 to $0.06 per thousand tokens. A thousand tokens is roughly 750 words, so small projects are really not a big financial commitment. My free trial came with 18 USD of credits, of which I have so far barely managed to spend 5%.

Let’s take a closer look at how it works, and what can be done with it!

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Animate Your Robot In Blender

May 11, 2022 by Anne Ogborn 10 Comments

You’ve built a robot crammed full of servos and now you settle down for the fun part, programming your new dancing animatronic bear! The pain in your life is just beginning. Imagine that you decide the dancing bear should raise it’s arm. If you simply set a servo position, the motor will slew into place as fast as it can. What you need is an animation, and preferably with smooth acceleration.

You could work through all the math yourself. After half an hour of fiddling with the numbers, the bear is gracefully raising it’s arm like a one armed zombie. And then you realize that the bear has 34 more servos.

Fortunately for everybody who’s done the above, there’s Blender. It’s all about creating smooth motion for animations and computer graphics. Making robot motion with Blender is, if not easy, at least tolerable. We made a sample project, a 3-axis robot arm to illustrate. It has a non-moving pedestal, rotating base, upper arm, and lower arm. We’ll be animating it first in Blender and then translating the file over to something we can use to drive the servos with a little script.

Now, Blender is notorious for a difficult user interface. The good news is that, with revision 2.9, it moved to a much more normal interface. It still definitely is a large program, with 23 different editors and literally thousands of controls, but we’ll only be using a small subset to make our robot move. We won’t teach you Blender here, because there are thousands of great Blender tutorials online. You want to focus on animation, and the Humane Rigging series is particularly recommended.

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Arm Pumps Up The Volume With Mbed And A Potentiometer

April 19, 2022 by Al Williams 7 Comments

Last time, I told you how to get started with the “Black Pill” STM32F411 board using the Mbed OS. The example program, admittedly, didn’t use many of the features of the OS, unless you count what the USB serial port driver uses behind the scenes. However, this time, we’ll make a practical toy that lets you adjust your PC’s volume level with a pot.

The Black Pill is a good choice for this application since it has analog inputs and can act as a USB keyboard. In fact, the Mbed OS has drivers for all kinds of USB devices. We’ve seen the serial port, but you can also look like a mass storage device or a mouse, for example. Just for practice, we’ll create two threads of execution. One will read the pot and send a message over to the other thread. That thread will communicate with the PC as a USB keyboard. Any computer that understands media keys on a keyboard should work with the device.

Threads

Creating threads is very simple. For many cases, you just define a void function that takes no arguments and use it with a Thread object:

readknobThread.start(vol_thread);

Of course, the function shouldn’t return unless you want the thread to end. As I mentioned in the last post, you can sleep with the ThisThread::sleep_for call. There is also a yield call if you simply want to give up the time slice without sleeping for a specific amount of time.

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Arming With An OS

April 13, 2022 by Al Williams 28 Comments

We see tons of projects with the infamous “Blue Pill” STM32 boards. They are cheap and plentiful and have a lot of great features, or at least they were before the chip shortage. I recently picked up a “Black Pill”, which is very similar but has an even more powerful processor. For a few bucks, you get an ARM CPU that can run at 100 MHz (but with USB, probably 96 MHz). There’s 512 kB of flash and 128 kB of RAM. There’s a USB type C port, and even a button and an LED onboard. The thing fits on a breadboard and you can program it with a cheap STLink dongle which costs about $10.

Of course, you then have to consider the software. The STM32Cube stuff is a lot to set up and learn but it does let you do just about anything you can imagine. Then there is the STM32Duino plug-in that lets you use it as a beefy Arduino. That works and is easy enough to set up. However, there’s also Mbed. The only problem is that Mbed doesn’t work right out of the box. Turns out, though, it isn’t that hard to set up. I’ll show you how easy it is to get things going and, next time, I’ll show you a practical example of a USB peripheral that uses the mBed RTOS features.

First Steps

Obviously, you are going to need a Black Pill. There are at least two choices but for as cheap as they are there is little reason not to get the STM32F411 version that has more memory. The DIP form factor will fit in whatever breadboard you happen to have and a USB C cable will power the board so unless you are driving a lot of external circuitry, you probably don’t need an external supply.

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