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,...
Introduction to Microcontrollers - Further Beginnings
●3 commentsEmbedded Programming Basics This tutorial entry will discuss some further embedded programming basics that you will need to understand before proceeding on to the LED blinky and other example programs. We will do this by looking at the...
Introduction to Microcontrollers - Hello World
●3 comments[quicklinks] Embedded Hello World A standard first program on an embedded platform is the blinking LED. Getting an LED to blink demonstrates that you have your toolchain set up correctly, that you are able to download your program...
From Baremetal to RTOS: A review of scheduling techniques
●5 commentsTransitioning 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....
How to Estimate Encoder Velocity Without Making Stupid Mistakes: Part II (Tracking Loops and PLLs)
●1 commentYeeehah! Finally we're ready to tackle some more clever ways to figure out the velocity of a position encoder. In part I, we looked at the basics of velocity estimation. Then in my last article, I talked a little about what's necessary to...
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...
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...
How to Build a Fixed-Point PI Controller That Just Works: Part II
●4 commentsIn Part I we talked about some of the issues around discrete-time proportional-integral (PI) controllers: various forms and whether to use the canonical form for z-transforms (don't do it!) order of operation in the integral term: whether to...
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...
Using the Beaglebone PRU to achieve realtime at low cost
●4 commentsIntroduction 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...
Chebyshev Approximation and How It Can Help You Save Money, Win Friends, and Influence People
●1 commentWell... 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...
