Getting Started With Zephyr: DTS vs DTSI vs Overlays
Devicetrees can be daunting for traditional embedded software engineers that are new to Zephyr. In this blog post, I address these fears and show how navigating Devicetrees can be much easier if you understand that they represent the layered structure of the underlying hardware.
Getting Started With Zephyr: Using GDB To Fix a Driver Bug
In this blog post, I show how to use GDB to debug an issue encountered with a TSL2591 light sensor driver in Zephyr. The fix was submitted and successfully incorporated into The Zephyr Project.
C to C++: Using Abstract Interfaces to Create Hardware Abstraction Layers (HAL)
In C to C++, we've been exploring how to transition from a C developer to a C++ developer when working in embedded system. In this post, we will explore how to leverage classes to create hardware abstraction layers (HAL). You'll learn about the various inheritance mechanisms, what an virtual function is, and how to create an abstract class.
The three laws of safe embedded systems
This short article is part of an ongoing series in which I aim to explore some techniques that may be useful for developers and organisations that are beginning their first safety-related embedded project.
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.
Hidden Gems from the Embedded Online Conference Archives - Part 3
Jack Ganssle shows us what we can learn by studying previous failures - and why this is essential for anyone working in embedded systems.
Linear Feedback Shift Registers for the Uninitiated, Part XV: Error Detection and Correction
Lost Secrets of the H-Bridge, Part V: Gate Drives for Dummies
Learn the most important issues in power MOSFET and IGBT gate drives: - Transistor behavior during switching - Calculating turn-on and turn-off times - Passive components used between gate drive IC and transistor - Reverse recovery - Capacitively-coupled spurious turn-on - Factors that influence a good choice of turn-on and turn-off times - Gate drive supply voltage management - Bootstrap gate drives - Design issues impacting reliability
Hidden Gems from the Embedded Online Conference Archives - Part 2
A look back at a deep dive into the Mars Perseverance flight software from one of the technical leads at JPL.
OS influence on power consumption
Power consumption of an embedded system may be influenced in software in general, but selection of an operating system can be key.
On optimizing manual soldering
When faced with manual soldering of thousands of components, speed and efficiency become pivotal. Here are some takeaways from my own experience attempting to optimize such a process.
On hardware state machines: How to write a simple MAC controller using the RP2040 PIOs
Hardware state machines are nice, and the RP2040 has two blocks with up to four machines each. Their instruction set is limited, but powerful, and they can execute an instruction per cycle, pushing and popping from their FIFOs and shifting bytes in and out. The Raspberry Pi Pico does not have an Ethernet connection, but there are many PHY boards available… take a LAN8720 board and connect it to the Pico; you’re done. The firmware ? Introducing Mongoose…
Graphical medicine
Although an appealing user interface is a good option for any device, in medical applications it can be a life saver.
Pay it Forward
A popular car bumper sticker reads, "If you can read this, thank a teacher!" I might say, "If you can read THIS (article on Embedded Related), then you've been blessed with great experiences and/or great educators or volunteers that got you excited about tech and helped you believe that you had a future in this field!" Why not pay it forward by helping other children have those same great experiences? As we enter another season of giving, I hope you consider doing what you can to support the hundreds or thousands of non-profit organizations, educators, and volunteers around the world who are getting kids excited about tech the same way YOU got excited about tech. In this article, I'll share with you a handful of organizations that I know of or donate to that have this mission. How do you like to give back?
Zephyr: West Manifest For Application Development
In this blog post, I show a simpler way to create custom West manifest files. This technique eliminates the need to duplicate the complex West manifest from upstream Zephyr. I also show how we can use the West manifest to include out-of-tree board and SoC definitions, and include our own out-of-tree drivers.
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...
Cortex-M Exception Handling (Part 1)
This article describes how Cortex-M processors handle interrupts and, more generally, exceptions, a concept that plays a central role in the design and implementation of most embedded systems.
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...
Important Programming Concepts (Even on Embedded Systems) Part II: Immutability
Other articles in this series: Part I: Idempotence Part III: Volatility Part IV: Singletons Part V: State Machines Part VI: Abstraction This article will discuss immutability, and some of its variations in the topic of functional...
Development of the MOS Technology 6502: A Historical Perspective
One ubiquitous microprocessor of the late 1970s and 1980s was the MOS Technology MCS 6502. I included a section on the development of the 6502 in Part 2 of Supply Chain Games, and have posted it as an excerpt here, as I believe it is deserving...
Cutting Through the Confusion with ARM Cortex-M Interrupt Priorities
The insanely popular ARM Cortex-M processor offers very versatile interrupt priority management, but unfortunately, the multiple priority numbering conventions used in managing the interrupt priorities are often counter-intuitive, inconsistent,...
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...
Project Log: Pixelblaze Christmas Lights
Festive fun and the hacker spirit combine in my janky attempt to adorn my house with addressable LEDs! In this post, I show you how I used a Pixelblaze and a cheap strip of WS2811 RGB LEDs (and not a little bit of hot glue and paper clips) to make a super cool set of Christmas lights.
Getting Started With Zephyr: Using GDB To Fix a Driver Bug
In this blog post, I show how to use GDB to debug an issue encountered with a TSL2591 light sensor driver in Zephyr. The fix was submitted and successfully incorporated into The Zephyr Project.
Unuglify C++ FSM with DSL
Domain Specific Languages (DSL) are an effective way to avoid boilerplate or repetitive code. Using DSLs lets the programmer focus on the problem domain, rather than the mechanisms used to solve it. Here I show how to design and implement a DSL using the C++ preprocessor, using the FSM library, and the examples I presented in my previous articles.
