Unraveling the Enigma: Object Detection in the World of Pixels
Exploring the realm of embedded systems co-design for object recognition, this blog navigates the convergence of hardware and software in revolutionizing industries. Delving into real-time image analysis and environmental sensing, the discussion highlights advanced object detection and image segmentation techniques. With insights into Convolutional Neural Networks (CNNs) decoding pixel data and autonomously extracting features, the blog emphasizes their pivotal role in modern computer vision. Practical examples, including digit classification using TensorFlow and Keras on the MNIST dataset, underscore the power of CNNs. Through industry insights and visualization aids, the blog unveils a tapestry of innovation, charting a course towards seamless interaction between intelligent embedded systems and the world.
Finite State Machines (FSM) in Embedded Systems (Part 1) - There's a State in This Machine!
An introduction to state machines and their implementation. Working from an intuitive definition of the state machine concept, we will start with a straightforward implementation then we evolve it into a more robust and engineered solution.
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.
++i and i++ : what’s the difference?
Although the ++ and -- operators are well known, there are facets of their operation and implementation that are less familiar to many developers.
Using GPIO in (Apache) NuttX RTOS
In the previous article (https://embeddedrelated.com/showarticle/1610.php) we saw how to compile and run NuttX on three low cost boards (RaspberryPi Pico, ESP32-Devkit and STM32F4Discovery). Today we will see how to use GPIO pins and read and write logic level signals from/to the MCU pins.
Everybody knows that blinking a LED is the "Hello World" program of embedded system engineer. Controlling a GPIO we can do exactly that! Although it is important to know that NuttX...
A Sneak Peek at the 2024 Embedded Online Conference
The embedded systems industry is evolving at a rapid pace. Just a few years ago, most embedded products were disconnected systems that used bare-metal scheduling techniques. Today, the drive to connect devices and add intelligence at the edge is revolutionizing how we build embedded products. The only way to stay current and not get left behind is to learn and network with colleagues and industry experts continuously.
This year, the 2024 Embedded Online Conference is...
The Asimov Protocol
While the Internet is choke-full of explanations of basic data communication protocols, very little is said about the higher levels of packing, formatting, and exchanging information in a useful and practical way. This less-charted land is still fraught with strange problems, whose solutions may be found in strange places – in this example, a very short, 60 years old Science Fiction story.
Ten Little Algorithms, Part 7: Continued Fraction Approximation
In this article we explore the use of continued fractions to approximate any particular real number, with practical applications.
Embedded Developer’s New Year’s Resolution
As we reach the end of another year, while wrapping up this one, we also contemplate the year ahead. Though nothing major might change on the 1st of January, it’s nice to pause during the holidays to reflect on the past and plan for future improvements.
I like to plan my professional improvements, and I always include them in my New Year’s resolution. Here are some ideas that I’d like to share.
Good Software Design PracticesYes, we Embedded developers love...
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...
The DSP Online Conference - Right Around the Corner!
It is Sunday night as I write this blog post with a few days to go before the virtual doors of the very first DSP Online Conference open..
It all started with a post in the DSPRelated forum about three months ago. We had just had a blast running the 2020 Embedded Online Conference and we thought it could be fun to organize a smaller event dedicated to the DSP community. So my goal with the post in the forum was to see if...
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.
Beware of Analog Switch Leakage Current
I’ve written about leakage current of CMOS circuitry several times previously, but it’s always been as a warning tossed aside, something to scare inexperienced youngsters, like the boogeyman or the chupacabra. Today I want to show you a specific example.
Let’s say I want to make a switchable reference that takes a 1.25V reference voltage and either buffers it or multiplies it by a gain of 2. I have three ideas of circuits that will do this:
In all cases, I have a...
How to Analyze a Three-Op-Amp Instrumentation Amplifier
There is a useful circuit called an instrumentation amplifier which has several subtle advantages. Back in 2014 I wrote an article called How to Analyze a Differential Amplifier, which is a circuit that comes up so often that every electrical engineer should just know it.
This gives you a gain of \( K \) from input to output if \( R3/R1 = R4/R2 = K \):
$$V_\text{out} - V_\text{ref} = K\left(V_P - V_N\right)$$
If you don’t get the resistor ratios exactly equal...
Libgpiod - Toggling GPIOs The Right Way In Embedded Linux
OverviewWe 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...
Getting Started With Zephyr: West Manifest Customization
IntroductionThe Zephyr Project RTOS (https://zephyrproject.org/), or simply “Zephyr” as it is known colloquially, is an increasingly popular real-time operating system due to its native support for over 450 boards and countless peripherals. When starting with any embedded software project, the first task is to start from a known baseline. This can include cloning a repository from source control, which can be the case with embedded Linux, or downloading a zip file representing a...
Second-Order Systems, Part I: Boing!!
I’ve already written about the unexciting (but useful) 1st-order system, and about slew-rate limiting. So now it’s time to cover second-order systems.
The most common second-order systems are RLC circuits and spring-mass-damper systems.
Spring-mass-damper systems are fairly common; you’ve seen these before, whether you realize it or not. One household example of these is the spring doorstop (BOING!!):
(For what it’s worth: the spring...
Levitating Globe Teardown, Part 1
I've been kicking some ideas around for a long time for a simple and inexpensive platform I could use for control systems experimentation for the beginner. I want something that can be controlled easily in a basic fashion, yet that provides some depth: I want to be able to present ever-more challenging goals to the student, that can be attained by fancier control algorithms all on the same device.
I'm currently looking at magnetic levitation. It's fun, it has the potential to be...
New Comments System (please help me test it)
I thought it would take me a day or two to implement, it took almost two weeks...
But here it is, the new comments systems for blogs, heavily inspired by the forum system I developed earlier this year.
Which means that:
- You can easily add images, either by drag and drop or through the 'Insert Image' button
- You can add MathML, TeX and ASCIImath equations and they will be rendered with Mathjax
- You can add code snippets and they will be highlighted with highlights.js
- You can edit...
Slew Rate Limiters: Nonlinear and Proud of It!
I first learned about slew rate limits when I was in college. Usually the subject comes up when talking about the nonideal behavior of op-amps. In order for the op-amp output to swing up and down quickly, it has to charge up an internal capacitor with a transistor circuit that’s limited in its current capability. So the slew rate limit \( \frac{dV}{dt} = \frac{I_{\rm max}}{C} \). And as long as the amplitude and frequency aren’t too high, you won’t notice it. But try to...
Coding Step 1 - Hello World and Makefiles
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
Step 0 discussed how to install GCC and the make utility with the expectation of writing and compiling your first C program. In this article, I discuss how to use those tools we installed last time. Specifically, how to use GCC to compile a C program and...
Tolerance Analysis
Today we’re going to talk about tolerance analysis. This is a topic that I have danced around in several previous articles, but never really touched upon in its own right. The closest I’ve come is Margin Call, where I discussed several different techniques of determining design margin, and ran through some calculations to justify that it was safe to allow a certain amount of current through an IRFP260N MOSFET.
Tolerance analysis...
Oscilloscope Dreams
My coworkers and I recently needed a new oscilloscope. I thought I would share some of the features I look for when purchasing one.
When I was in college in the early 1990's, our oscilloscopes looked like this:
Now the cathode ray tubes have almost all been replaced by digital storage scopes with color LCD screens, and they look like these:
Oscilloscopes are basically just fancy expensive boxes for graphing voltage vs. time. They span a wide range of features and prices:...
Android for Embedded Devices - 5 Reasons why Android is used in Embedded Devices
The embedded purists are going to hate me for this. How can you even think of using Android on an embedded system ? It’s after all a mobile phone operating system/software.
Sigh !! Yes I did not like Android to begin with, as well - for use on an Embedded System. But sometimes I think the market and needs decide what has to be used and what should not be. This is one such thing. Over the past few years, I have learned to love Android as an embedded operating system....
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 programming.
There are a whole series of benefits to using program variables that… well, that aren’t actually variable, but instead are immutable. The impact of...
Finite State Machines (FSM) in Embedded Systems (Part 1) - There's a State in This Machine!
An introduction to state machines and their implementation. Working from an intuitive definition of the state machine concept, we will start with a straightforward implementation then we evolve it into a more robust and engineered solution.
Padé Delay is Okay Today
This article is going to be somewhat different in that I’m not really writing it for the typical embedded systems engineer. Rather it’s kind of a specialized topic, so don’t be surprised if you get bored and move on to something else. That’s fine by me.
Anyway, let’s just jump ahead to the punchline. Here’s a numerical simulation of a step response to a \( p=126, q=130 \) Padé approximation of a time delay:
Impressed? Maybe you should be. This...
++i and i++ : what’s the difference?
Although the ++ and -- operators are well known, there are facets of their operation and implementation that are less familiar to many developers.
Arduino robotics #4 - HC-SR04 ultrasonic sensor
Arduino Robotics
Arduino robotics is a series of article chronicling my first autonomous robot build, Clusterbot. This build is meant to be affordable, relatively easy and instructive. The total cost of the build is around $50.
1. Arduino robotics - motor control2. Arduino robotics - chassis, locomotion and power3. Arduino robotics - wiring, coding and a test run4.
