A New Related Site!
We are delighted to announce the launch of the very first new Related site in 15 years! The new site will be dedicated to the trendy and quickly growing field of Machine Learning and will be called - drum roll please - MLRelated.com.
We think MLRelated fits perfectly well within the “Related” family, with:
- the fast growth of TinyML, which is a topic of great interest to the EmbeddedRelated community
- the use of Machine/Deep Learning in Signal Processing applications, which is of...
Five ‘80s Movies that Inspired Me to Become an Engineer
Five ‘80s Movies that Inspired Me to Become an Engineer
Movies and pop culture can incredibly impact society, particularly children. However, we never really know what conversation, demonstration, or movie could inspire someone to become an engineer. Recently in the Beningo house, we ran out of the film to watch for movie night. In desperation, I decided to find great movies from my childhood in the 80s. To my surprise, I realized how influential several of these films inspired me to...
3 Overlooked Embedded Software Elements
Have you ever wondered, while you and your team are busy writing software if the foundation of how embedded software systems are built has changed and left you in the dust? What if while you were busily focusing on getting your product out the door, fighting bugs, and dealing with supply issues, there were techniques and processes that you completely overlooked that could save the day? I’ve found three elements embedded software teams often underutilize that could dramatically improve...
Learning A New Microcontroller
Contents:- Introduction
- The Peripherals
- System Complexity
- Support Software
- Do It Like Phil
- The Programs
- WET And DRY Code
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 in its own right.
(Note: MOS Technology is pronounced with the individual letters M-O-S “em oh ess”,[1] not “moss”, and should not be confused with another semiconductor company,
Supply Chain Games: What Have We Learned From the Great Semiconductor Shortage of 2021? (Part 2)
Welcome back! Today we’re going to zoom around again in some odd directions, and give a roundabout introduction to the semiconductor industry, touching on some of the following questions:
- How do semiconductors get designed and manufactured?
- What is the business of semiconductor manufacturing like?
- What are the different types of semiconductors, and how does that affect the business model of these manufacturers?
- How has the semiconductor industry evolved over...
Patterns of Thinking: Metaphors in Programming
Several years ago, I once attended an “Object-Oriented Analysis and Design” training. As most such courses go, the instructor began with brushing up on the fundamental OO concepts. When explaining inheritance, the instructor spontaneously compared inheriting from a class to passing traits from parents to the offspring in a family. At first, this “family tree” metaphor seemed to make a lot of sense and most attendees nodded approvingly. However, when the instructor discussed...
New Promo Video for the 2022 Embedded Online Conference
Less than a week to go before the conference! Check out our 2022 Embedded Online Conference promo video, featuring (in order of appearance) Helen Leigh, Peter McLaughlin, Jack Ganssle, Tyler Hoffman, Steve Branam, Colin O'Flynn, Miro Samek, Henk Muller, Jacob Beningo, Harrison Donahue, Kate Stewart, Clive (Max) Maxfield, Don Wilcher, Adam Taylor, and Jean Labrosse.
If you haven't registered for the conference yet, please consider doing so today. Make sure to use the...
2022 Embedded Online Conference - Final Push!
With the Embedded Online Conference only a couple of weeks away, we are now doing a final push to ensure that as many engineers as possible who could benefit from the conference are aware of it.
If you'd like to help us spread the word, not only will you make our day, but you'll also earn a chance to win one of TWO Saleae Logic Pro 8.
Prize: TWO Saleae Logic Pro 8Raffle...From Baremetal to RTOS: A review of scheduling techniques
Transitioning from bare-metal embedded software development to a real-time operating system (RTOS) can be a difficult endeavor. Many developers struggle with the question of whether they should use an RTOS or simply use a bare-metal scheduler. One of the goals of this series is to walk developers through the transition and decision making process of abandoning bare-metal thinking and getting up to speed quickly with RTOSes. Before diving into the details of RTOSes, the appropriate first step...
STM32 VS Code Extension Under The Hood
VS Code is becoming the "go to" environment for many developers. Increasingly, toolchain providers are publishing VS Code extensions and ST has recently followed suit. Additionally, CMake is significantly growing in popularity, with many projects adopting it for its ease of use and flexibility. This video shows how the STM32 VS Code extension works under the hood and how to get more out of it.
Specifically, we'll review the CMake files generated by the VS Code extension and how to modify...
Coroutines in one page of C
A coroutine is a function that you can jump back into after returning from it - and it remembers where it was in the code, and all the variables. This is very useful at times.
One use is generating a sequence of values. Here's how you can generate all the x,y pairs in a 2D range in Python:
def iterate(max_x, max_y): for x in range(max_x): for y in range(max_y): yield x,y for x,y in iterate(2,2): print x,yThis prints:
0 0 0 1 1 0 1 1The yield keyword is like...
Ten Little Algorithms, Part 5: Quadratic Extremum Interpolation and Chandrupatla's Method
Today we will be drifting back into the topic of numerical methods, and look at an algorithm that takes in a series of discretely-sampled data points, and estimates the maximum value of the waveform they were sampled from.
The Other Kind of Bypass Capacitor
There’s a type of bypass capacitor I’d like to talk about today.
It’s not the usual power supply bypass capacitor, aka decoupling capacitor, which is used to provide local charge storage to an integrated circuit, so that the high-frequency supply currents to the IC can bypass (hence the name) all the series resistance and inductance from the power supply. This reduces the noise on a DC voltage supply. I’ve...
Fluxions for Fun and Profit: Euler, Trapezoidal, Verlet, or Runge-Kutta?
Today we're going to take another diversion from embedded systems, and into the world of differential equations, modeling, and computer simulation.
DON'T PANIC!First of all, just pretend I didn't bring up anything complicated. We're exposed to the effects of differential equations every day, whether we realize it or not. Your car speedometer and odometer are related by a differential equation, and whether you like math or not, you probably have some comprehension of what's going on: you...
Elliptic Curve Cryptography - Basic Math
An introduction to the math of elliptic curves for cryptography. Covers the basic equations of points on an elliptic curve and the concept of point addition as well as multiplication.
Using the C language to program the am335x PRU
IntroductionSome weeks ago, I published an article on how we used the PRU to implement a power supply control loop having hard realtime constraints:
//www.embeddedrelated.com/showarticle/586.php
Writing this kind of logic in assembly language is not easy. First the assembly language itself may be difficult to learn depending on your background. Then, fixed and floating point arithmetics require lot of code. While macros help to handle the complexity, they still are error prone as you...
Designing Communication Protocols, Practical Aspects
For most embedded developers always comes the time when they have to make their embedded MCU talk to another system. That other system will be a PC or a different embedded system or a smartphone etc. For the purpose of this article I am assuming that we are in the control of the protocol between the two ends and we don’t have to follow something that is already in place on one side.
So let’s say that we have our embedded MCU, we have implemented and configured the USB stack (or just...
Using a RTLSDR dongle to validate NRF905 configuration
I am currently working on a system to monitor the garage door status from my flat. Both places are 7 floors apart, and I need to send the data wirelessly. I chose to operate on the 433MHz carrier, and I ordered 2 PTR8000 modules: http://www.electrodragon.com/w/NRF905_Transceiver_433MHz-Wireless_ModuleThe PTR8000 is based on the dual band sub 1GHz NRF905 chipset from NORDICSEMI: http://www.nordicsemi.com/eng/Products/Sub-1-GHz-RF/nRF905I...Signal Processing Contest in Python (PREVIEW): The Worst Encoder in the World
When I posted an article on estimating velocity from a position encoder, I got a number of responses. A few of them were of the form "Well, it's an interesting article, but at slow speeds why can't you just take the time between the encoder edges, and then...." My point was that there are lots of people out there which take this approach, and don't take into account that the time between encoder edges varies due to manufacturing errors in the encoder. For some reason this is a hard concept...
Coding - Step 0: Setting Up a Development Environment
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
You can easily find a million articles out there discussing compiler nuances, weighing the pros and cons of various data structures or discussing the optimization of databases. Those sorts of articles are fascinating reads for advanced programmers but...
Introduction to Microcontrollers - Adding Some Real-World Hardware
When 2 LEDs Just Don't Cut It AnymoreSo far, we've done everything in this series using two LEDs and one button. I'm guessing that the thrill of blinking an LED has worn off by now, hard as that is to imagine. What's more, we've just about reached the limits of what we can learn with such limited I/O. We have come to the point where we need to add some hardware to our setup to continue with additional concepts and microcontroller...
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...
Digital PLL's -- Part 2
In Part 1, we found the time response of a 2nd order PLL with a proportional + integral (lead-lag) loop filter. Now let’s look at this PLL in the Z-domain [1, 2]. We will find that the response is characterized by a loop natural frequency ωn and damping coefficient ζ.
Having a Z-domain model of the DPLL will allow us to do three things:
Compute the values of loop filter proportional gain KL and integrator gain KI that give the desired loop natural...Bad Hash Functions and Other Stories: Trapped in a Cage of Irresponsibility and Garden Rakes
I was recently using the publish() function in MATLAB to develop some documentation, and I ran into a problem caused by a bad hash function.
In a resource-limited embedded system, you aren't likely to run into hash functions. They have three major applications: cryptography, data integrity, and data structures. In all these cases, hash functions are used to take some type of data, and deterministically boil it down to a fixed-size "fingerprint" or "hash" of the original data, such that...
StrangeCPU #2. Sliding Window Token Machines
Summary:An in-depth exploration of Sliding Window Token Machines; ARM notes.
Table of Contents:- Part 1: A new CPU - technology review, re-examination of the premises; StrangeCPU concepts; x86 notes.
- Part 2: Sliding-Window Token Machines, an in-depth exploration of this curious technology; ARM notes.
- Part 3. Instruction Slides - The Strangest CPU Yet! Decoding instructions with a Sliding Window...
Using XML to describe embedded devices (and speak to them)
This article discusses one of the typical development cycles in embedded device and communication design and presents a possible, light weight solution using the free DClib/netpp framework.
The challengeAssume we're faced with the design of an embedded device, be it a simple SoC unit or a more complex, uC controlled engine with various attached peripherals. From first prototype to the market, the following development cycle is typically walked through:
10 More (Obscure) Circuit Components You Should Know
The interest in my previous article on obscure but useful electronics parts, "10 Circuit Components You Should Know" was encouraging enough that I thought I would write a followup. So here are another 10:
1. "Ideal Diode" controllers
Load-sharing circuits use diodes tied together at their cathode terminal to take the most positive voltage among the sources and connect it to a load. Works great: you have a DC/DC power supply, a battery, and a solar cell, and it will use whichever output is...