VolksEEG: Rust Development On Adafruit nRF52840 Feather Express
Contents: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 evaluate it.
My conclusion? Do it!
Most of the rest of us participants are primarily C/C++ embedded developers. I had previously been sensitized to Rust for embedded systems by
Six Software Design Tools
Contents: IntroductionHere are six tools to help you with software design. The first two are very simple, almost deceptively trivial, while the last four are more involved. They apply universally, to all types of software, all types of systems, and all languages. This is part of good engineering discipline.
At face value, this is just a bunch of acronyms,...
Introducing The VolksEEG Project
IntroductionThe VolksEEG project is an open-source project with the goal of creating an electroenchephalogram (EEG) machine, fully cleared by the FDA for standard clinical use. All designs will be freely available for others to manufacture.
The project was founded by Alan Cohen, a medical device systems engineer with an electrical engineering/software (EE/SW) background in Boston, USA, and Dr. Bryan Glezerson
Video-Based STEM Embedded Systems Curriculum, Part 2
Contents:- Introduction
- Lesson Plan 1: Introducing Arduino
- Lesson Plan 2: Circuit Drawings With Fritzing
- Lesson Plan 3: Basic Electronics
- Coming Soon
This post continues from part 1. It contains the first three lesson plans.
Lesson Plan 1: Introducing ArduinoThis lesson is first because Arduino is the simplest programming environment, yet allows lots of interaction with hardware. In...
Video-Based STEM Embedded Systems Curriculum, Part 1
Contents:- Introduction
- Adapting To Your Circumstances
- Suggested Policies
- The Video Educators
- Equipment, Books, and Supplies
- Lesson Summary
- Suggested Teaching Method
Review: Prototype to Product
Prototype to Product: A Practical Guide for Getting to Market, by Alan Cohen, is a must-read for anyone involved in product development, whether in a technical, management, or executive role.
I was reminded of it by Cohen's recent episode on Embedded.fm, 388: Brains Generate EMF, which is worth listening to a couple times through, especially if you're interested in medical device development. And in fact his first episode there,
Dumb Embedded System Mistakes: Running The Wrong Code
ContentsSimple Automated Log Processing
Text log data offers a wealth of information from an embedded system. At least during prototyping and development phases, most systems have some kind of serial log output, or use semihosting methods to log to a serial output channel in a debugger. Then you can capture the logs to a file.
The problem is that they tend to accumulate large volumes of data. Logs can be many thousands of lines long, especially when you run long duration tests. Finding information and evaluating trends in the...
C to C++: 3 Proven Techniques for Embedded Systems Transformation
For 50 years, the C programming language has dominated the embedded software industry. Even today, more than 80% of embedded projects are using C; however, over the last few years, many teams have begun transitioning from C to C++. C++ offers embedded developers a robust, modern set of tools that can be used to write flexible, scalable, and reusable applications. As embedded applications become more complex and connected, teams need a more modern language to help them deal with the software...
Donald Knuth Is the Root of All Premature Optimization
This article is about something profound that a brilliant young professor at Stanford wrote nearly 45 years ago, and now we’re all stuck with it.
TL;DRThe idea, basically, is that even though optimization of computer software to execute faster is a noble goal, with tangible benefits, this costs time and effort up front, and therefore the decision to do so should not be made on whims and intuition, but instead should be made after some kind of analysis to show that it has net...
Unit Tests for Embedded Code
I originate from an electrical engineering background and my first industry experience was in a large, staid defense contractor. Both of these experiences contributed to a significant lack of knowledge with regards to software development best practices. Electrical engineers often have a backwards view of software in general; large defense contractors have similar views of software and couple it with a general disdain for any sort of automation or ‘immature’ practices. While there...
Are We Shooting Ourselves in the Foot with Stack Overflow?
Most traditional, beaten-path memory layouts allocate the stack space above the data sections in RAM, even though the stack grows “down” (towards the lower memory addresses) in most embedded processors. This arrangement puts your program data in the path of destruction of a stack overflow. In other words, you violate the first Gun Safety Rule (ALWAYS keep the gun pointed in a safe direction!) and you end up shooting yourself in the foot. This article shows how to locate the stack at the BEGINNING of RAM and thus point it in the "safe" direction.
Best Firmware Architecture Attributes
Architecture of a firmware (FW) in a way defines the life-cycle of your product. Often companies start with a simple-version of a product as a response to the time-to-market caveat of the business, make some cash out of the product with a simple feature set. It takes only less than 2-3 years to reach a point where the company needs to develop multiple products derived from the same code base and multiple teams need to develop...
The CRC Wild Goose Chase: PPP Does What?!?!?!
I got a bad feeling yesterday when I had to include reference information about a 16-bit CRC in a serial protocol document I was writing. And I knew it wasn’t going to end well.
The last time I looked into CRC algorithms was about five years ago. And the time before that… sometime back in 2004 or 2005? It seems like it comes up periodically, like the seventeen-year locust or sunspots or El Niño,...
Interfacing LINUX with microcontrollers
IntroductionI am increasingly asked to work on small spare time projects where a user needs to control some device over the INTERNET. Recently, a friend needed to control heater relays and measure the temperature of its geographically distant secondary house. Another case relates to the control of a pan tilt home monitoring camera. A last one is the control of an old XY plotter DACs.
In both applications, the user wants to access the system over a web browser using HTTP. From the user...
Open-Source Licenses Made Easy with Buildroot and Yocto for Embedded Linux
In this article I will try to explain what are the copyrights/copyleft, what are the popular opensource software licenses, and how to make sure that your Embedded Linux system complies with them using popular build systems ; Buildroot or YOCTO projec
Important Programming Concepts (Even on Embedded Systems) Part IV: Singletons
Other articles in this series:
- Part I: Idempotence
- Part II: Immutability
- Part III: Volatility
- Part V: State Machines
- Part VI: Abstraction
Today’s topic is the singleton. This article is unique (pun intended) in that unlike the others in this series, I tried to figure out a word to use that would be a positive concept to encourage, as an alternative to singletons, but
Coding Step 3 - High-Level Requirements
Articles in this series:
- Coding Step 0 - Development Environments
- Coding Step 1 - Hello World and Makefiles
- Coding Step 2- Source Control
- Coding Step 3 - High-Level Requirements
- Coding Step 4 - Design
If this series of articles has been light on one thing it's 'coding'. If it's been light on two things the second is 'embedded'. In three articles I haven't gotten past Hello World on a desktop PC. That changes (slowly) with this article. In this article I'll...
Review: Embedded Software Design: A Practical Approach to Architecture, Processes, and Coding Techniques
IntroductionFull disclosure: I was given a copy of this book to review.
Embedded Software Design: A Practical Approach to Architecture, Processes, and Coding Techniques, by Jacob Beningo, is an excellent introduction to strategies for embedded systems design and bringing those designs to fruition. Renowned embedded systems expert Jack Ganssle was the technical reviewer.
This is a practical how-to book on the modern professional practice of embedded systems...
Coding Step 2 - Source Control
Articles in this series:
- Coding Step 0 - Development Environments
- Coding Step 1 - Hello World and Makefiles
- Coding Step 2 - Source Control
- Coding Step 3 - High-Level Requirements
- Coding Step 4 - Design
When I first started out in programming, version control was not an introductory topic. Not in the least because it required a 'server' (ie, a computer which a teenaged me couldn't afford) but because it seemed difficult and only useful to teams rather than...
Interfacing LINUX with microcontrollers
IntroductionI am increasingly asked to work on small spare time projects where a user needs to control some device over the INTERNET. Recently, a friend needed to control heater relays and measure the temperature of its geographically distant secondary house. Another case relates to the control of a pan tilt home monitoring camera. A last one is the control of an old XY plotter DACs.
In both applications, the user wants to access the system over a web browser using HTTP. From the user...
C to C++: Bridging the Gap from C Structures to Classes
In our last post, C to C++: Proven Techniques for Embedded Systems Transformation, we started to discuss the different ways that C++ can be used to write embedded software. You saw that there is no reason to be overwhelmed by trying to adopt complex topics like metaprogramming out of the gate. An important concept to understand is that you can make the transition gradually into C++ while still receiving the many benefits that C++ has to offer.
One of the first concepts that a C...
Introduction to Microcontrollers - Ada - 7 Segments and Catching Errors
7 Segments the Ada WayHere is the Ada version (I should say AN Ada version) of the 7 segment multiplexing code presented in the last installment. The hardware now is the STM32F407 Discover board, which is a Cortex M4F board. There are lots of differences in GPIO and timer setup, but if you understoold the previous code in C you should not have much trouble understanding this code in Ada.
As interesting as the Ada approach to the task is the Ada ability to detect...
How to make a heap profiler
We'll see how to make a heap profiler. Example code for this post makes up heapprof, a working 250-line heap profiler for programs using malloc/free.
It works out of the box on Linux (tested on "real" programs like gdb and python). The main point though is being easy to port and modify to suit your needs. The code, build and test scripts are at github.
Why roll your own heap profiler?
- It's easy! And fun, if you're that sort of person. What, not reasons enough? OK, how...
Jaywalking Around the Compiler
Our team had another code review recently. I looked at one of the files, and bolted upright in horror when I saw a function that looked sort of like this:
void some_function(SOMEDATA_T *psomedata) { asm volatile("push CORCON"); CORCON = 0x00E2; do_some_other_stuff(psomedata); asm volatile("pop CORCON"); }There is a serious bug here — do you see what it is?
A wireless door monitor based on the BANO framework
IntroductionI have been thinking for a while about a system to monitor the states of my flat and my garage doors from a remote place. Functionnaly, I wanted to monitor the state of my doors from a remote place. A typical situation is when I leave for holidays, but it can also be useful from the work office. To do so, I would centralize the information on a server connected on the Internet that I could query using a web browser. The server itself would be located in the appartement, where...