Data Hiding in C
Strictly speaking, C is not an object-oriented language. Although it provides some features that fit into the object-oriented paradigm it has never had the full object-oriented focus that its successor C++ offers. C++ introduced some very useful concepts and abilities that I miss when I’m developing in ANSI C. One such concept is protected member variables and functions.
When you declare a class in C++ you can also declare member variables and functions as part of that class. Often, these...
Chebyshev Approximation and How It Can Help You Save Money, Win Friends, and Influence People
Well... maybe that's a stretch. I don't think I can recommend anything to help you win friends. Not my forte.
But I am going to try to convince you why you should know about Chebyshev approximation, which is a technique for figuring out how you can come as close as possible to computing the result of a mathematical function, with a minimal amount of design effort and CPU power. Let's explore two use cases:
- Amy has a low-power 8-bit microcontroller and needs to compute \( \sqrt{x} \)...
Welcome to my life!
Hi folks!
As an electronic engineer the most of my work is about making new designs where a microcontroller is present in 99.9 % of the applications. Since 2003 I am self-employed and do consultants work for different companies. I have been traveling to different parts of the world doing work for DeLaval International, a company that makes automation equipment for the dairy industry. A lot of the things I have done for them involves use of different Atmel AVR...
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...
Lightweight hardware abstraction
Some lessons are tougher than others to master. You would think that hard fought battles would be easier to remember, but sometimes it just does not work that way. Recently, I was asked to pick-up a project that had been managed by another employee. The project was yet another cost reduction project. The hardware group was tasked with updating a currently shipping product, to reduce the existing failure rate, while at the same time to remove cost from the...
Embedded Software Creation II - European Normative & Legislation
In this post I will explain the European Normative. I will answer the main questions and I will be open to answer all the doubts any of you could have. Please leave a comment and I will answer if i could.
Why I need to look and accomplish some standards?The main reason is if you want to comercialize the product in the European Union, if exists any European Directive that cover the product, the product must be marked with the CE mark. For USA it work in the same way by the...
C++ on microcontrollers 4 – input pins, and decoding a rotary switch
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.
So far I...
Modulation Alternatives for the Software Engineer
Before I get to talking about modulation, here's a brief diversion.
A long time ago -- 1993, to be precise -- I took my first course on digital electronics and processors. In that class, we had to buy a copy of the TTL Data Book* from Texas Instruments.
If you have any experience in digital logic design you probably know that TTL stands for Transistor-transistor logic (thereby making the phrase "TTL Logic" an example of RAS...
C++ on microcontrollers 3 – a first shot at an hc595 class with 8 output pins
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.
In the first part of...
A true pioneer passes away... A farewell to Ritchie.
We all have our heroes. We all have people who were important to our professional developments. For me, Dennis Ritchie was one of those people. I was an early adopter of the C programming language. Back in the very early 80's a friend and neighbor had excitedly shared with me his copy of "The C Programming Language" by Kernighan and Ritchie. At first I was a non-believer. I had for several years been a happy and productive assembly language...
Coding Step 4 - Design
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
The last article in this series discussed how to write functional high-level requirements: specifications for what your software is supposed to do. Software design is the other side of the coin....
“Smarter” cars, unintended acceleration – and unintended consequences
In this article, I consider some recent press reports relating to embedded software in the automotive sector.
In The Times newspaper (London, 2015-10-16) the imminent arrival of Tesla cars that “use autopilot technology to park themselves and change lane without intervention from the driver” was noted.
By most definitions, the Tesla design incorporates what is sometimes called “Artificial Intelligence” (AI).Others might label it a “Smart” (or at least “Smarter”)...
Favorite Tools: C++11 User-defined literals
In many software domains units of measurement are frequently critical to the software's data processing requirements. Those same units, or rather the use of the wrong units, are often the source of bugs and disastrous mistakes. Although useful for other purposes, user-defined literals are an excellent addition to the C++11 standard and handy when working with units of measurement.
Suppose a device measures velocity. To help prevent errors, the software specification requires...
Tenderfoot: Recommended Reading
Twenty years ago I read Code Complete by Steve McConnell. And then read it again. And again. And again. Of all the books I have read during my career, I believe this was the book that catapulted me from a young electrical engineer to a young and aspiring embedded software engineer. So to all the ‘tenderfoots’ embarking upon an embedded systems and especially embedded software and firmware career, this entry is for you.
First, I would certainly recommend that all engineers read and read...
Is it a Bug or an Error?
Probably you’ve heard the story of how Adm. Grace Hopper attached a moth that was dislodged from a relay in the Harvard Mark II mainframe to an engineering notebook and labeled it the “First actual case of bug being found.”
Designers of electronics, including Thomas Edison, had been using the term bug for decades. But it was mostly after this amusing 1947 event hat the use of words like “bugs” and “debugging” took off in the emerging software realm.
So why is it that if a...
AI at the Edge - Can I run a neural network in a resource-constrained device?
Hello Related Communities,
This is my first time blogging since joining Stephane in November. He and I were at Embedded World together and he asked me to write about some of the important trends as they relate to all of you. I expect to post others in the near future, but the biggest trend in the embedded space was all of the activity around artificial intelligence (AI) at the edge.
This trend caught me a bit by surprise. I have been doing a lot of reading about AI over the last...
Thumb Rules for Effective Meetings
Meetings are unavoidable at any work place. At most occasions, meetings can be frustrating. We all face meeting-nightmares in our professional life.
I worked on a project, where none of the team-members were ever interested in any kind of group discussion or formal communication. At early stages of the project, no one wanted to be a part of decision making process. During middle-stages of the project, no one wanted to share any status updates or discuss any critical issues. And finally when...
Deeply embedded design example - Logic replacement
I have always believed that some of the low-cost, low-pin count, low-resource microprocessors would make an excellent choice for the replacement of discrete logic components. In these cases the deeply embedded microprocessor would become less of a general purpose computer and more of a logic replacement, providing a prescribed function with no connection to the outside world. In a world of bigger, faster and more expensive, it is a pleasant change of pace...
Embedded Software Creation II - European Normative & Legislation
In this post I will explain the European Normative. I will answer the main questions and I will be open to answer all the doubts any of you could have. Please leave a comment and I will answer if i could.
Why I need to look and accomplish some standards?The main reason is if you want to comercialize the product in the European Union, if exists any European Directive that cover the product, the product must be marked with the CE mark. For USA it work in the same way by the...
Lightweight hardware abstraction
Some lessons are tougher than others to master. You would think that hard fought battles would be easier to remember, but sometimes it just does not work that way. Recently, I was asked to pick-up a project that had been managed by another employee. The project was yet another cost reduction project. The hardware group was tasked with updating a currently shipping product, to reduce the existing failure rate, while at the same time to remove cost from the...
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.
In the last two weeks, I’ve had the opportunity to discuss the contents of my previous article on this site with a group of very smart and enthusiastic engineers in Cairo (Egypt). As part of this discussion, it has become clear that I should add a few more details to explain the work...
Favorite Tools: C++11 User-defined literals
In many software domains units of measurement are frequently critical to the software's data processing requirements. Those same units, or rather the use of the wrong units, are often the source of bugs and disastrous mistakes. Although useful for other purposes, user-defined literals are an excellent addition to the C++11 standard and handy when working with units of measurement.
Suppose a device measures velocity. To help prevent errors, the software specification requires...
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
VolksEEG: Rust Development On Adafruit nRF52840 Feather Express
Contents: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
Embedded Software Creation I - Methodologies
The first knowledge we need it is to know the posibilities or methodologies that exists to create Software. Each methodology is used to develop diferent types of Software. The types usually are defined by the requeriments and the diferent normative that is related to the type of device. In the next post I will explain how to find the normative@ legislation (link), and how does it work.
Let's start with methodologies. There are lot's of methodologies and so many people that develop...
Debugging DSP code.
I am fascinated with neural network processing and have been playing with them since the 80's.
I am a frequent contributor to the Numenta forum. Numenta is the current project of Jeff Hawins, the guy that gave us the Palm Pilot. They are working with the HTM model. This is a system based on studies of the functions of the cortical column and has some very interesting properties: It processes sequential data streams and has very effective one shot learning. The data is arranged in Sparse...
Embedded Software Creation II - European Normative & Legislation
In this post I will explain the European Normative. I will answer the main questions and I will be open to answer all the doubts any of you could have. Please leave a comment and I will answer if i could.
Why I need to look and accomplish some standards?The main reason is if you want to comercialize the product in the European Union, if exists any European Directive that cover the product, the product must be marked with the CE mark. For USA it work in the same way by the...
Libgpiod - Toggling GPIOs The Right Way In Embedded Linux
Overview
We all know that GPIO is one of the core elements of any embedded system. We use GPIOs to control LEDs and use them to monitor switches and button presses. In modern embedded systems, GPIOs can also be used as pins for other peripheral busses, such as SPI and I2C. Similar to the previous article on interacting with peripherals on an SPI bus in userspace via SPIdev (https://www.embeddedrelated.com/showarticle/1485.php), we can also control GPIOs from userspace on an embedded...
A true pioneer passes away... A farewell to Ritchie.
We all have our heroes. We all have people who were important to our professional developments. For me, Dennis Ritchie was one of those people. I was an early adopter of the C programming language. Back in the very early 80's a friend and neighbor had excitedly shared with me his copy of "The C Programming Language" by Kernighan and Ritchie. At first I was a non-believer. I had for several years been a happy and productive assembly language...
