Digital PLL's -- Part 1
1. Introduction Figure 1.1 is a block diagram of a digital PLL (DPLL). The purpose of the DPLL is to lock the phase of a numerically controlled oscillator (NCO) to a reference signal. The loop includes a phase detector to compute ...
Best Firmware Architecture Attributes
●1 commentArchitecture 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...
A few uses for an autonomous vehicle
From the time technology that we have come to know was invented, it has been used to gain an advantage militarily or to make life easier. Military usage seems to be a driving factor, but it is not the only factor. Guerilla tactics played...
Stability or insanity
I've just spent over two weeks getting ready to do my next video. It was a combination of one of those vast underestimations one occasionally makes, combined with falling into a bit of an obsession.I am, at this point, not only wondering if...
Beyond the RTOS: A Better Way to Design Real-Time Embedded Software
An RTOS (Real-Time Operating System) is the most universally accepted way of designing and implementing embedded software. It is the most sought after component of any system that outgrows the venerable "superloop". But it is also the design...
Data Types for Control & DSP
There's a lot of information out there on what data types to use for digital signal processing, but there's also a lot of confusion, so the topic bears repeating.I recently posted an entry on PID control. In that article I glossed over the data...
Embedded Firmware Refactoring, Optimisation and Migration
Legacy products are often based on older hardware platforms which often become under-powered or run out of memory which constrains further product development. Customers are always looking for new features and improved performance but...
Basic Sensors for an Autonomous Vehicle
●1 commentThe following are a few basic sensors that can be used to help an autonomous vehicle navigate its environment.The faster the vehicle is traveling, the faster the sensor must be processed. Moving vehicles could knock something over or...
3 Good News
Good News #1 Last week, I announced a new and ambitious reward program that will be funded by the new Vendors Directory. This week, I am happy to announce that we have our firsts two sponsors! Quantum Leaps & Abelon Systems have...
Cutting Through the Confusion with ARM Cortex-M Interrupt Priorities
●1 commentThe insanely popular ARM Cortex-M processor offers very versatile interrupt priority management, but unfortunately, the multiple priority numbering conventions used in managing the interrupt priorities are often counter-intuitive, inconsistent,...
Best Firmware Architecture Attributes
●1 commentArchitecture 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...
C++ on microcontrollers 1 - introduction, and an output pin class
●11 commentsThis 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...
Adventures in Signal Processing with Python
●1 commentAuthor’s note: This article was originally called Adventures in Signal Processing with Python (MATLAB? We don’t need no stinkin' MATLAB!) — the allusion to The Treasure of the Sierra Madre has been removed, in deference to being...
Cortex-M Exception Handling (Part 2)
●1 commentThe first part of this article described the conditions for an exception request to be accepted by a Cortex-M processor, mainly concerning the relationship of its priority with respect to the current execution priority. This...
Lost Secrets of the H-Bridge, Part IV: DC Link Decoupling and Why Electrolytic Capacitors Are Not Enough
●3 commentsThose of you who read my earlier articles about H-bridges, and followed them closely, have noticed there's some unfinished business. Well, here it is. Just so you know, I've been nervous about writing the fourth (and hopefully final) part of this...
Using the C language to program the am335x PRU
Introduction Some weeks ago, I published an article on how we used the PRU to implement a power supply control loop having hard realtime constraints: http://www.embeddedrelated.com/showarticle/586.php Writing this kind of logic in assembly...
Important Programming Concepts (Even on Embedded Systems) Part V: State Machines
●1 commentOther articles in this series: Part I: Idempotence Part II: Immutability Part III: Volatility Part IV: Singletons Part VI: Abstraction Oh, hell, this article just had to be about state machines, didn’t it? State machines! Those...
Analog-to-Digital Confusion: Pitfalls of Driving an ADC
●2 commentsImagine the following scenario:You're a successful engineer (sounds nice, doesn't it!) working on a project with three or four circuit boards. More than even you can handle, so you give one of them over to your coworker Wayne to design....
Boot sequence for an ARM based embedded system -2
●3 commentsIn the last post, we discussed about the startup execution sequence on an ARM based embedded system in broader terms. In this post, we are going to cover the details of a startup code.These details are also available through various ARM resources...
Introduction to Microcontrollers - Driving WS2812 RGB LEDs
●4 comments[quicklinks] This tutorial chapter is a bit of a detour, but I think an interesting and useful one. It introduces a bit of assembly language programming, and demonstrates bit-banging a tight serial data protocol. And it deals...
