Lightweight C++ Error-Codes Handling
The traditional C++ approach to error handling tends to distinguish the happy path from the unhappy path. This makes handling errors hard (or at least boring) to write and hard to read. In this post, I present a technique based on chaining operations that merges the happy and the unhappy paths. Thanks to C++ template and inlining the proposed technique is lightweight and can be used proficiently for embedded software.
Embedded Systems Roadmaps
What skills should every embedded systems engineer have? What should you study next to improve yourself as an embedded systems engineer? In this article I'll share with you a few lists from well-respected sources that seek to answer these questions, with the hope of helping provide you a path to mastery. Whether you've only just finished your first Arduino project or you've been building embedded systems for decades, I believe there's something in here for everyone to help improve themselves as embedded systems engineers.
Embedded Systems Co-design for Object Recognition: A Synergistic Approach
Embedded systems co-design for object recognition is essential for real-time image analysis and environmental sensing across various sectors. This methodology harmonizes hardware and software to optimize efficiency and performance. It relies on hardware accelerators, customized neural network architectures, memory hierarchy optimization, and power management to achieve benefits like enhanced performance, lower latency, energy efficiency, real-time responsiveness, and resource optimization. While challenges exist, co-designed systems find applications in consumer electronics, smart cameras, industrial automation, healthcare, and autonomous vehicles, revolutionizing these industries. As technology advances, co-design will continue to shape the future of intelligent embedded systems, making the world safer and more efficient.
What is Pulse Width Modulation and How Does It Work?
Pulse Width Modulation (PWM) is a technique used to control the average voltage supplied to a device or component by adjusting the width of a series of pulses. It works by rapidly turning a signal on and off at a specific frequency. The crucial element of PWM is the duty cycle, which represents the percentage of time the signal is “on” (high voltage) compared to the total time of one cycle.
Getting Started With Zephyr: Saving Data To Files
In this blog post, I show how to implement a Zephyr application to mount a microSD card, create a new file on the microSD card, and write data to it. The lessons learned from such an application can be helpful for devices out in the field that need to write data to off-board memory periodically, especially in cases where Internet access may be sporadic.
Elliptic Curve Cryptography - Extension Fields
An introduction to the pairing of points on elliptic curves. Point pairing normally requires curves over an extension field because the structure of an elliptic curve has two independent sets of points if it is large enough. The rules of pairings are described in a general way to show they can be useful for verification purposes.
Software is free and can right any wrong
Software changes are so much easier than hardware modifications, so the temptation is always to take this approach to fixing bugs. This may not always be a good idea.
Creating a Hardware Abstraction Layer (HAL) in C
In my last post, C to C++: Using Abstract Interfaces to Create Hardware Abstraction Layers (HAL), I discussed how vital hardware abstraction layers are and how to use a C++ abstract interface to create them. You may be thinking, that’s great for C++, but I work in C! How do I create a HAL that can easily swap in and out different drivers? In today’s post, I will walk through exactly how to do that while using the I2C bus as an example.
Elliptic Curve Cryptography - Key Exchange and Signatures
Elliptic curve mathematics over finite fields helps solve the problem of exchanging secret keys for encrypted messages as well as proving a specific person signed a particular document. This article goes over simple algorithms for key exchange and digital signature using elliptic curve mathematics. These methods are the essence of elliptic curve cryptography (ECC) used in applications such as SSH, TLS and HTTPS.
Square root in fixed point VHDL
We will design and implement a fixed point square root function in VHDL. The algorithm is based on the recursive inverse square root algorithm based on Newton Raphson and offers parametrizable pipeline depth, word length and the algorithm is built on records and procedures.
Return of the Delta-Sigma Modulators, Part 1: Modulation
About a decade ago, I wrote two articles: Modulation Alternatives for the Software Engineer (November 2011) Isolated Sigma-Delta Modulators, Rah Rah Rah! (April 2013) Each of these are about delta-sigma modulation, but they’re...
Linear Feedback Shift Registers for the Uninitiated, Part I: Ex-Pralite Monks and Finite Fields
Later there will be, I hope, some people who will find it to their advantage to decipher all this mess. — Évariste Galois, May 29, 1832 I was going to call this short series of articles “LFSRs for Dummies”, but...
Learning Rust For Embedded Systems
The Motivational PortionBased on recommendations from Kevin Nause, the VolksEEG project is considering using Rust as the embedded system programming language. So I've been off on a tear skimming books and e-books and watching videos at 2x to...
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...
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...
Thermistor signal conditioning: Dos and Don'ts, Tips and Tricks
In an earlier blog entry, I mentioned this circuit for thermistor signal conditioning: It is worth a little more explanation on thermistor signal conditioning; it's something that's often done poorly, whereas it's among the easiest...
How Embedded Linux is used in Spacecrafts !
This article dives into the application of Linux in spacecraft, examining the challenges it poses and proposing potential solutions. Real-life examples will be discussed, while also addressing the drawbacks of employing Linux in safety-critical missions.
Getting Started With Zephyr: Bluetooth Low Energy
In this blog post, I show how to enable BLE support in a Zephyr application. First, I show the necessary configuration options in Kconfig. Then, I show how to use the Zephyr functions and macros to create a custom service and characteristic for a contrived application.