Supply Chain Games: What Have We Learned From the Great Semiconductor Shortage of 2021? (Part 5)
In this article we’re going to take a look at cycle time, queues, and inventory. Cycle time is a manufacturing term — for anything, not just semiconductors — meaning how long it takes for an individual product to make its way through a manufacturing process, from start to finish. We’re going to try to understand how long it takes to manufacture semiconductors. In particular, we’re going to try to answer these questions:
- How long does it take...
Three more things you need to know when transitioning from MCUs to FPGAs
Take a look at three more important difference between FPGAs and MCUs: "code reuse" vs templating, metastability and blocking vs. non-blocking operations.
In the beginning, there was no code…
…and it was good.
Why is it that code starts out nice and deteriorates over time?
Getting Started With Zephyr: Devicetree Bindings
This blog post shines some light on how devicetrees are used in The Zephyr Project. Specifically, we understand the mechanisms that enable us to use nodes in the devicetree in the C source files. We use a sample provided in the Zephyr repository itself and work our way through portions of the Zephyr codebase to get insight into the mechanisms that make this possible.
Quaternions and the spatial rotations in motion enabled wearable devices. Exploiting the potential of smart IMUs attitude estimation.
Have you always wondered what a quaternion is? this is your post. Attitude or spatial orientation analysis is a powerful element in wearable devices (and many other systems). Commercially available sensors can provide this information out-of-the-box without requiring complex additional implementation of sensor fusion algorithms. Since these are already on-chip solutions devices can serve as a way to explore and analyze motion in several use cases. Mathematical analysis for processing quaternion is presented along with a brief introduction to them, Although they are not really easy to visualise, a couple fairly simple examples are provided which may allow you to gain some intuition on what's the logic behind them.
From Embedded Software Engineer to Musician
In his first blog post on EmbeddedRelated, Jean Labrosse, the author of the uC/OS series and founder of Micrium, discusses his transition from an embedded software engineer to a musician.
Bit-Banged Async Serial Output And Disciplined Engineering
This post covers implementing asynchronous serial output directly on a GPIO with bit-banging. This can be a valuable debug tool for getting information out of a system. It also covers disciplined engineering, using the bit-banging module as an example and template you can apply to other projects.
Jumping from MCUs to FPGAs - 5 things you need to know
Are you a microcontroller expert beckoned by the siren song of the FPGA? Not long ago, that was me. FPGA-expert friends of mine regularly extolled the virtues of these mysterious components and I wanted in. When I made the leap, I found a world seemingly very familiar, but in reality, vastly different. I found that my years of C programming and microcontroller use often gave pre preconceived interpretations of FPGA resource material which resulted in eye-roll class mistakes in my code. I’ve gleaned five things of vital importance to help you make that transition faster than I did.
Assembly language is best - except when it isn’t
A look at why writing in C often produces more efficient code than hand-written assembly language.
C to C++: 5 Tips for Refactoring C Code into C++
The article titled "Simple Tips to Refactor C Code into C++: Improve Embedded Development" provides essential guidance for embedded developers transitioning from C to C++. The series covers fundamental details necessary for a seamless transition and emphasizes utilizing C++ as a better C rather than diving into complex language features. The article introduces five practical tips for refactoring C code into C++. Replace #define with constexpr and const: Discouraging the use of #define macros, the article advocates for safer alternatives like constexpr and const to improve type safety, debugging, namespaces, and compile-time computation. Use Namespaces: Demonstrating the benefits of organizing code into separate logical groupings through namespaces, the article explains how namespaces help avoid naming conflicts and improve code readability. Replace C-style Pointers with Smart Pointers and References: Emphasizing the significance of avoiding raw pointers, the article suggests replacing them with C++ smart pointers (unique_ptr, shared_ptr, weak_ptr) and using references
In the beginning, there was no code…
…and it was good.
Why is it that code starts out nice and deteriorates over time?
So You Want To Be An Embedded Systems Developer
Contents:- Introduction
- What's An Embedded System?
- Hobbyist vs. Professional Hardware
- The Primary Resources
- Some Advanced Resources
- Some Hardware
- Glossaries
- Other Links
- Final Thought
nRF5 to nRF Connect SDK migration via DFU over BLE
This writeup contains some notes on how I was able to migrate one of my clients projects based on the nRF5 SDK, to nRF Connect SDK (NCS) based firmware, via a DFU to devices in the field over BLE.
The Backstreet Consultant
In the uncharted land between Arduino-wielding kids and qualified electronics engineers emerged an entirely new market for embedded work. In this article, based on my personal experience and observations, I will attempt to outline this young market, the forces operating within it, and the kinds of people involved.
A short historyUp until fifteen years ago, give or take, embedded design was done exclusively by trained professionals: not just because of the required technical know-how, but also...
Three more things you need to know when transitioning from MCUs to FPGAs
Take a look at three more important difference between FPGAs and MCUs: "code reuse" vs templating, metastability and blocking vs. non-blocking operations.
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,
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 \( \sqrt{x} \)...
Visual Studio Code Extensions for Embedded Software Development
Visual Studio Code has become one of the most popular IDEs in the world. To date, software developers have downloaded it more than 40 million times! I suspect you’ve at least heard of it, if not already attempting to use it. Visual Studio Code allows developers to easily customize their development environment which can help them accelerate development, minimize bugs, and make developing software overall much better.
One challenge with Visual Studio Code is that embedded software...
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...
Cracking the (embedded) Coding Interview
You never forget the day you land your first job.
The thrill of receiving that call from your recruiter to tell you that you bagged your dream role! The relief when you finally see the offer letter you’ve been working towards for years. The pride in your parents' voices when you call home and say “Hey look Ma, I’ve made it!”
But before that, there’s the grueling screening process to get through. Tech interviews often last up to three months and companies can have five...
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 them.
Well, first we need to get position. Quadrature encoders are incremental encoders, meaning they can only measure relative changes in position. They produce a pair of pulse trains, commonly called A and B, that look like...
My Love-Hate Relationship with Stack Overflow: Arthur S., Arthur T., and the Soup Nazi
Warning: In the interest of maintaining a coherent stream of consciousness, I’m lowering the setting on my profanity filter for this post. Just wanted to let you know ahead of time.
I’ve been a user of Stack Overflow since December of 2008. And I say “user” both in the software sense, and in the drug-addict sense. I’m Jason S, user #44330, and I’m a programming addict. (Hi, Jason S.) The Gravatar, in case you were wondering, is a screen...
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 \( \sqrt{x} \)...
Ten Little Algorithms, Part 2: The Single-Pole Low-Pass Filter
Other articles in this series:
- Part 1: Russian Peasant Multiplication
- Part 3: Welford's Method (And Friends)
- Part 4: Topological Sort
- Part 5: Quadratic Extremum Interpolation and Chandrupatla's Method
- Part 6: Green’s Theorem and Swept-Area Detection
I’m writing this article in a room with a bunch of other people talking, and while sometimes I wish they would just SHUT UP, it would be...
Thermistor signal conditioning: Dos and Don'ts, Tips and Tricks
In an earlier blog entry, I mentioned this circuit for thermistor signal conditioning:
It is worth a little more explanation on thermistor signal conditioning; it's something that's often done poorly, whereas it's among the easiest applications for signal conditioning.
The basic premise here is that there are two resistors in a voltage divider: Rth is the thermistor, and Rref is a reference resistor. Here Rref is either R3 alone, or R3 || R4, depending on the gain...
VHDL tutorial - part 2 - Testbench
In an earlier article I walked through the VHDL coding of a simple design. In this article I will continue the process and create a test bench module to test the earlier design. The Xilinx ISE environment makes it pretty easy to start the testing process. To start the process, select "New Source" from the menu items under "Project". This launches the "New Source Wizard". From within the Wizard select "VHDL Test Bench" and enter the name of the new module (click 'Next' to...
Zebras Hate You For No Reason: Why Amdahl's Law is Misleading in a World of Cats (And Maybe in Ours Too)
I’ve been wasting far too much of my free time lately on this stupid addicting game called the Kittens Game. It starts so innocently. You are a kitten in a catnip forest. Gather catnip.
And you click on Gather catnip and off you go. Soon you’re hunting unicorns and building Huts and studying Mathematics and Theology and so on. AND IT’S JUST A TEXT GAME! HTML and Javascript, that’s it, no pictures. It’s an example of an
Using the Beaglebone PRU to achieve realtime at low cost
Introduction
I work as an engineer in a synchrotron facility. A few weeks ago, I helped the people in charge of the power supply developments to integrate a realtime control algorithm on a prototype platform: a BeagleBone Black (BBB) running Linux. I had already worked with this board in the past, and I found it very interesting given its excellent resources versus price ratio (around 40 euros). This time, I was impressed by its realtime capabilities. I thought it would be a good idea to...
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...
StrangeCPU #1. A new CPU
Summary: In this multi-part series I will share with you a design, implementation notes and code for a slightly different kind of a CPU featuring a novel token machine that resolves an 8-bit token to pretty much any address in a 32-bit or even 64-bit address space, using not much more than an adder.
Table of Contents:- Part 1: A new CPU - technology review, re-examination of the premises; StrangeCPU concepts; x86 notes.
