Why Should Unit Tests Feel Like Simulations?
Unit tests are designed to test units of software, but what exactly is a unit of software? It can be a function or a method, a class, or even an entire module.
If you're just starting with unit testing, chances are you're testing the implementation of a function or a method. Consequently, if the implementation changes, you must update your tests as well, which can render the entire process pointless. This is often the case with small pieces of code, particularly in embedded development,...
Getting Started With Zephyr: Devicetrees
This blog post provides an introduction to the "Devicetree", another unique concept in The Zephyr Project. We learn about the basic syntax of a device tree and how its structure and hierarchy mirror hardware, from the SoC to the final board. We also see how hardware described in a devicetree can be referenced and controlled in the source code of a Zephyr-based application.
NULL pointer protection with ARM Cortex-M MPU
This post explains how you can set up the ARM Cortex-M MPU (Memory Protection Unit) to protect thy code from dragons, demons, core dumps, and numberless other foul creatures awaiting thee after thou dereference the NULL pointer.
Call for Bloggers!
Are you passionate about embedded systems? Do you have valuable insights, tips, or stories to share with the embedded community? Do you want to reach a large and engaged audience of embedded enthusiasts and professionals? We are currently looking at adding a few more inspired writers to our team of bloggers.
Bellegram, a wireless DIY doorbell that sends you a Telegram message
A wireless button that uses the M5 STAMP PICO and Mongoose to send a Telegram message when pressed. The code is written in C
Getting Started with (Apache) NuttX RTOS Part 2 - Looking Inside and Creating Your Customized Image
In the previous article (https://www.embeddedrelated.com/showarticle/1524.p...) we saw how to run NuttX RTOS using the SIMulator. Today we will see how NuttX's directory tree is organized and how to use the menuconfig to enable some applications, including some tricks to search and solve dependencies.
NuttX Directories organization:
If you have previously compiled the Linux kernel or the U-Boot bootloader you will see that the NuttX source tree organization is very...
Moulding the Embedded Systems Engineers of Tomorrow: Adapting to a Constantly Transforming Technological Terrain
Embedded systems engineers, previously focused on device architecture, are now steering the digital era, encompassing firmware, software, complex silicon, and cloud computing. To keep pace, mastery in new areas like cybersecurity, artificial intelligence (AI), machine learning (ML), and cloud technologies is critical. In today's highly connected world, security is foundational to design, necessitating knowledge in encryption, secure coding, and data protection laws. Additionally, expertise in AI and ML is essential for managing vast global data, requiring understanding of ethical implications and effective system design for data analysis. The advent of cloud technology mandates learning about cloud architectures and data security. In this fast-paced field, continuous learning and adapting these new skills is the key to staying relevant and spearheading future advancements.
Getting Started With Zephyr: Kconfig
In this blog post, we briefly look at Kconfig, one of the core pieces of the Zephyr infrastructure. Kconfig allows embedded software developers to turn specific subsystems on or off within Zephyr efficiently and control their behavior. We also learn how we can practically use Kconfig to control the features of our application using the two most common mechanisms.
An Iterative Approach to USART HAL Design using ChatGPT
Discover how to leverage ChatGPT and an iterative process to design and generate a USART Hardware Abstraction Layer (HAL) for embedded systems, enhancing code reusability and scalability. Learn the step-by-step journey, improvements made, and the potential for generating HALs for other peripherals.
Modern C++ in Embedded Development: (Don't Fear) The ++
While C is still the language of choice for embedded development, the adoption of C++ has grown steadily. Yet, reservations about dynamic memory allocation and fears of unnecessary code bloat have kept many in the C camp. This discourse aims to explore the intricacies of employing C++ in embedded systems, negotiating the issues of dynamic memory allocation, and exploiting the benefits of C++ offerings like std::array and constexpr. Moreover, it ventures into the details of the zero-overhead principle and the nuanced distinctions between C and C++. The takeaway? Armed with the right knowledge and a careful approach, C++ can indeed serve as a powerful, safer, and more efficient tool for embedded development.
Back from Embedded World 2019 - Funny Stories and Live-Streaming Woes
When the idea of live-streaming parts of Embedded World came to me, I got so excited that I knew I had to make it happen. I perceived the opportunity as a win-win-win-win.
- win #1 - Engineers who could not make it to Embedded World would be able to sample the huge event,
- win #2 - The organisation behind EW would benefit from the extra exposure
- win #3 - Lecturers and vendors who would be live-streamed would reach a (much) larger audience
- win #4 - I would get...
C to C++: 5 Tips for Refactoring C Code into C++
The article titled "Simple Tips to Refactor C Code into C++: Improve Embedded Development" provides essential guidance for embedded developers transitioning from C to C++. The series covers fundamental details necessary for a seamless transition and emphasizes utilizing C++ as a better C rather than diving into complex language features. The article introduces five practical tips for refactoring C code into C++. Replace #define with constexpr and const: Discouraging the use of #define macros, the article advocates for safer alternatives like constexpr and const to improve type safety, debugging, namespaces, and compile-time computation. Use Namespaces: Demonstrating the benefits of organizing code into separate logical groupings through namespaces, the article explains how namespaces help avoid naming conflicts and improve code readability. Replace C-style Pointers with Smart Pointers and References: Emphasizing the significance of avoiding raw pointers, the article suggests replacing them with C++ smart pointers (unique_ptr, shared_ptr, weak_ptr) and using references
Getting Started With Zephyr: Devicetree Overlays
In this blog post, I show how the Devicetree overlay is a valuable construct in The Zephyr Project RTOS. Overlays allow embedded software engineers to override the default pin configuration specified in Zephyr for a particular board. In this blog post, I use I2C as an example. Specifically, I showed the default I2C pins used for the nRF52840 development kit in the nominal Zephyr Devicetree. Then, I demonstrated how an overlay can be used to override this pin configuration and the final result.
Introduction to Microcontrollers - Beginnings
Welcome to this Introduction to Microcontroller Programming tutorial series. If you are looking to learn the basics of embedded programming for microcontrollers (and a bit of embedded hardware design as well), I hope these tutorials will help you along that journey. These are my first postings here, and I am writing this tutorial series because over the years I have seen countless newbies asking the same questions and tripping over the same stumbling blocks, and I thought I might be able to...
Quaternions and the spatial rotations in motion enabled wearable devices. Exploiting the potential of smart IMUs attitude estimation.
Have you always wondered what a quaternion is? this is your post. Attitude or spatial orientation analysis is a powerful element in wearable devices (and many other systems). Commercially available sensors can provide this information out-of-the-box without requiring complex additional implementation of sensor fusion algorithms. Since these are already on-chip solutions devices can serve as a way to explore and analyze motion in several use cases. Mathematical analysis for processing quaternion is presented along with a brief introduction to them, Although they are not really easy to visualise, a couple fairly simple examples are provided which may allow you to gain some intuition on what's the logic behind them.
Getting Started With Zephyr: Devicetree Bindings
This blog post shines some light on how devicetrees are used in The Zephyr Project. Specifically, we understand the mechanisms that enable us to use nodes in the devicetree in the C source files. We use a sample provided in the Zephyr repository itself and work our way through portions of the Zephyr codebase to get insight into the mechanisms that make this possible.
How FPGAs work, and why you'll buy one
Today, pretty much everyone has a CPU, a DSP and a GPU, buried somewhere in their PC, phone, car, etc. Most don't know or care that they bought any of these, but they did.
Will everyone, at some future point, also buy an FPGA? The market size of FPGAs today is about 1% of the annual global semiconductor sales (~$3B vs ~$300B). Will FPGA eventually...
Modern C++ in Embedded Development: (Don't Fear) The ++
While C is still the language of choice for embedded development, the adoption of C++ has grown steadily. Yet, reservations about dynamic memory allocation and fears of unnecessary code bloat have kept many in the C camp. This discourse aims to explore the intricacies of employing C++ in embedded systems, negotiating the issues of dynamic memory allocation, and exploiting the benefits of C++ offerings like std::array and constexpr. Moreover, it ventures into the details of the zero-overhead principle and the nuanced distinctions between C and C++. The takeaway? Armed with the right knowledge and a careful approach, C++ can indeed serve as a powerful, safer, and more efficient tool for embedded development.
How to Estimate Encoder Velocity Without Making Stupid Mistakes: Part I
Here's a common problem: you have a quadrature encoder to measure the angular position of a motor, and you want to know both the position and the velocity. How do you do it? Some people do it poorly -- this article is how not to be one of them.
Well, first we need to get position. Quadrature encoders are incremental encoders, meaning they can only measure relative changes in position. They produce a pair of pulse trains, commonly called A and B, that look like...
Already 3000+ Attendees Registered for the Upcoming Embedded Online Conference
Chances are you already know, through the newsletter or banners on the Related sites, about the upcoming Embedded Online Conference.
Chances are you also already know that you have until the end of the month of February to register for free.
And chances are that you are one of the more than 3000 pro-active engineers who have already registered.
But If you are like me and have a tendency to do tomorrow what can be done today, maybe you haven't registered yet. You may...
Introduction to Microcontrollers - Driving WS2812 RGB LEDs
This tutorial chapter is a bit of a detour, but I think an interesting and useful one. It introduces a bit of assembly language programming, and demonstrates bit-banging a tight serial data protocol. And it deals with RGB LEDs, which are just very fun in their own right, especially these new parts. So I thought I'd post this to give readers time for some holiday lighting experimenting.
Back To The FutureRemember how we started this...
MSP430 LaunchPad Tutorial - Part 3 - ADC
In this new episode of our journey into MSP430 I will explain the basics of Analog to Digital Conversion on the MSP430G2231.We will write a program that will read an ADC channel and will toggle some leds based on the result of the conversion.
We start as usual with the inclusion of the header file for the MSP430G2231, the leds stuff and with the definition of a variable that will store the result of the conversion. We also declare a function that will initialize the ADC...
So You Want To Be An Embedded Systems Developer
Contents:
- Introduction
- What's An Embedded System?
- Hobbyist vs. Professional Hardware
- The Primary Resources
- Some Advanced Resources
- Some Hardware
- Glossaries
- Other Links
- Final Thought
Boot Sequence for an ARM based embedded system
Hello all,
Allow me to introduce myself. I am Deeksha and I come from plains of North India. My tryst with embedded technologies has been 5 years long and every single day I am amazed with the vastness and learning involved. The thing with embedded technologies is either you are into it, or you aren't. You cannot just hang around half-heartedly (I guess that holds true for every field, for that matter).You have to keep the learning and sharing process going on. And that is the reason I am...
Important Programming Concepts (Even on Embedded Systems) Part I: Idempotence
There are literally hundreds, if not thousands, of subtle concepts that contribute to high quality software design. Many of them are well-known, and can be found in books or the Internet. I’m going to highlight a few of the ones I think are important and often overlooked.
But first let’s start with a short diversion. I’m going to make a bold statement: unless you’re a novice, there’s at least one thing in computer programming about which you’ve picked up...
Introduction to Microcontrollers - Interrupts
It's Too Soon To Talk About Interrupts!That, at least, could be one reaction to this chapter. But over the years I've become convinced that new microcontroller programmers should understand interrupts before being introduced to any complex peripherals such as timers, UARTs, ADCs, and all the other powerful function blocks found on a modern microcontroller. Since these peripherals are commonly used with interrupts, any introduction to them that does not...
C++ on microcontrollers 1 - introduction, and an output pin class
This blog series is about the use of C++ for modern microcontrollers. My plan is to show the gradual development of a basic I/O library. I will introduce the object-oriented C++ features that are used step by step, to provide a gentle yet practical introduction into C++ for C programmers. Reader input is very much appreciated, you might even steer me in the direction you find most interesting.
I am lazy. I am also a programmer. Luckily, being a lazy...
10 Software Tools You Should Know
Unless you're designing small analog electronic circuits, it's pretty hard these days to get things done in embedded systems design without the help of computers. I thought I'd share a list of software tools that help me get my job done. Most of these are free or inexpensive. Most of them are also for working with software. If you never have to design, read, or edit any software, then you're one of a few people that won't benefit from reading this.
Disclaimer: the "best" software...
Using the C language to program the am335x PRU
Introduction
Some weeks ago, I published an article on how we used the PRU to implement a power supply control loop having hard realtime constraints:
//www.embeddedrelated.com/showarticle/586.php
Writing this kind of logic in assembly language is not easy. First the assembly language itself may be difficult to learn depending on your background. Then, fixed and floating point arithmetics require lot of code. While macros help to handle the complexity, they still are error prone as you...
Introduction to Microcontrollers - Hello World
Embedded Hello WorldA standard first program on an embedded platform is the blinking LED. Getting an LED to blink demonstrates that you have your toolchain set up correctly, that you are able to download your program code into the μC, and that the μC and associated circuitry (e.g. the power supply) is all working. It can even give you good evidence as to the clock rate that your microcontroller is running (something that trips up a great many people,...
