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Welcome to all the devoted readers of Circuit Cellar. Issue #412 of our magazine opens with your humble editor searching for the link that connects all the articles into one unified theme. Connectivity, in all its different communication protocols, capabilities, and performance characteristics, offers the most dominant theme for this month’s issue as we look at protocols like LoraWAN, Bluetooth, Matter, Google Thread, and Amazon Alexa. Some projects here use the ubiquitous Raspberry PI RP2040, while others may not. But you will find deep explorations into wireless protocol configurations. Even if some content does not communicate through radio frequency waves, others build links from the abstract to the tangible. What could a Dungeons and Dragons die roller and a diffusion-limited aggregator teach us about connectivity? I encourage you to explore further and draw inferences.
The first project to feature connectivity is Pedro Bertoleti’s examination of the LoRaWAN protocol. Who needs another way to send signals through the air when we have options as ubiquitous as Bluetooth? LoraWAN is purpose-built for applications that need to send low-bandwidth signals at distances longer than the Bluetooth range. It is adept at preserving battery life because of the limited scope of work it must perform to send collected data to the cloud. Regarding the total cost of ownership of an IoT system, it makes sense to use LoRaWAN to send limited amounts of data over longer distances than it might for Bluetooth. Pedro further examines the protocol’s strengths and technical features and offers examples of Smart Cities applications.
Robert Lacoste picks up the wireless communications theme later in our issue in the fifth installment of his “No Blues with Bluetooth!” series. With cyber-attacks on the rise, he delves into the Bluetooth Low Energy Security Manager. He describes the critical piece of the software stack designed to make mobile devices more secure when sending personal data over the air. Sometimes, BLE safeguards are turned off for convenience, but Robert tells us how to build more protection from snoops and would-be burglars.
Andrew Levido tells us how he built a better connection with his daughter with his Dungeons and Dragons Die Roller project. His daughter is a big fan of the fantasy role-playing game, and his project is impressive, considering that there is a display for every multi-faceted die the game requires. I could imagine a project like this having some potential in the consumer market, but then again, my daughter is also a big fan of D&D and takes pride in bringing her own physical dice to each campaign. Perhaps the commercial appeal may not be as great as I initially thought, but that’s not the point.
A team of students from Cornell University marveled at frost crystals forming on a window during a chilly morning in Ithaca, New York. Rather than complain about the heat leakage, they developed a diffusion-limited aggregator with an RP2040 and an inertial measurement unit. Technology gave them insight into a natural process where random particles combine to form impressive structures.
Many readers may have custom IoT gadgets around the house that might be controlled through a laptop or smartphone. Brian Millier provides the methodology to control his heat pump through voice commands via Amazon Alexa. He provides two examples of how to set them up: one by emulating a store-bought voice-activated product and the other by custom configuration.
Speaking of IoT gadgets around the house, Jeff Bachiochi connects his smart thermostat project to Google Matter in his latest “From the Bench” column. He notes that there have been many attempts to standardize around a home automation protocol, but Matter is one of the more recent and exciting efforts.
This month’s cover story features the latest efforts to turn passenger vehicles into rolling entertainment centers.
Issue Table of Contents can be found here,
as articles are made available online they will be linked.
PUBLISHED IN CIRCUIT CELLAR MAGAZINE • November #412 – Get a PDF of the issue
Tom Murphy has been plying his trade as a technology journalist for more than 25 years, first as an editor/writer/reporter and then as a communications professional. He has earned industry recognition for both journalistic endeavors and technology campaigns. Before joining Circuit Cellar magazine as editor-in-chief (2024), Tom wrote tech briefs, newsletters, blogs, press releases, white papers, and technical articles for numerous clients, primarily in the semiconductor industry. His introduction into the industry came as an editor for “Electronic News” covering microprocessor companies, the fabless semiconductor phenomena, communication chips, and many others. When he’s not tapping away at the keyboard, Tom learns Dungeons and Dragons terminology from his 10-year-old daughter and walks his bulldog (slowly) around the block.
