Next Newsletter: Embedded Boards

Coming to your inbox tomorrow: Circuit Cellar’s Embedded Boards newsletter. Tomorrow’s newsletter content focuses on both standard and non-standard embedded computer boards that ease prototyping efforts and let you smoothly scale up to production volumes.

Bonus: We’ve added Drawings for Free Stuff to our weekly newsletters. Make sure you’ve subscribed to the newsletter so you can participate.

Already a Circuit Cellar Newsletter subscriber? Great!
You’ll get your
Embedded Boards newsletter issue tomorrow.

Not a Circuit Cellar Newsletter subscriber?
Don’t be left out! Sign up now:

Our weekly Circuit Cellar Newsletter will switch its theme each week, so look for these in upcoming weeks:

Analog & Power. (7/2) This newsletter content zeros in on the latest developments in analog and power technologies including DC-DC converters, AC-DC converters, power supplies, op amps, batteries and more.

Microcontroller Watch (7/9) This newsletter keeps you up-to-date on latest microcontroller news. In this section, we examine the microcontrollers along with their associated tools and support products.

IoT Technology Focus. (7/16) Covers what’s happening with Internet-of-Things (IoT) technology–-from devices to gateway networks to cloud architectures. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

Tuesday’s Newsletter: IoT Tech Focus

Coming to your inbox tomorrow: Circuit Cellar’s IoT Technology Focus newsletter. Tomorrow’s newsletter covers what’s happening with Internet-of-Things (IoT) technology–-from devices to gateway networks to cloud architectures. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

Bonus: We’ve added Drawings for Free Stuff to our weekly newsletters. Make sure you’ve subscribed to the newsletter so you can participate.

Already a Circuit Cellar Newsletter subscriber? Great!
You’ll get your IoT Technology Focus newsletter issue tomorrow.

Not a Circuit Cellar Newsletter subscriber?
Don’t be left out! Sign up now:

Our weekly Circuit Cellar Newsletter will switch its theme each week, so look for these in upcoming weeks:

Embedded Boards.(6/25) The focus here is on both standard and non-standard embedded computer boards that ease prototyping efforts and let you smoothly scale up to production volumes.

Analog & Power. (7/2) This newsletter content zeros in on the latest developments in analog and power technologies including DC-DC converters, AD-DC converters, power supplies, op amps, batteries and more.

Microcontroller Watch (7/9) This newsletter keeps you up-to-date on latest microcontroller news. In this section, we examine the microcontrollers along with their associated tools and support products.

July Circuit Cellar: Sneak Preview

The July issue of Circuit Cellar magazine is out next week! This 84-page publication will make a satisfying thud sound when it lands on your desk and it’s crammed full of excellent embedded electronics articles prepared for you.

Not a Circuit Cellar subscriber?  Don’t be left out! Sign up today:

 

Here’s a sneak preview of July 2019 Circuit Cellar:

CONNECTED SYSTEMS IN ACTION

Embedded Computing
in Railway Systems
Railway systems keep getting more advanced. On both the control side and passenger entertainment side, embedded computers and power supplies play critical roles. Railway systems need sophisticated networking, data collection and real-time control, all while meeting safety standards. Circuit Cellar Chief Editor Jeff Child looks at the latest technology trends and products relevant to railway applications.

Product Focus:
IoT Interface Modules
The fast growing IoT phenomenon is driving demand for highly integrated modules designed for the IoT edge. Feeding those needs, a new crop of IoT modules have emerged that offer pre-certified solutions that are ready to use. This Product Focus section updates readers on this technology trend and provides a product album of representative IoT modules.

TECHNOLOGIES AND TECHNIQUES FOR ENGINEERS

FPGA Signal Processing
Offering the dual benefits of powerful signal processing and system-level integration, FPGAs have become a key technology for embedded system developers. Makers of chip and board-level FPGA products are providing complete solutions to enable developers to meet their application needs. Circuit Cellar Chief Editor Jeff Child explores the latest technology trends and product developments in FPGA signal processing.

Macros for AVR Assembler Programming
The AVR microcontroller instruction set provides a simplicity that makes it good for learning the root principles of machine programming. There’s also a rich set of macros available for the AVR that ease assembler-level programming. In this article, Wolfgang Matthes steps you through these principles, with the goal of helping programmers “think low-level, write high-level” when they approach embedded systems software development.

Inrush Current Limiters in Action
At the moment a high-power system is switched on, high loads can result in serious damage—even when the extra load is only for short time. Inrush current limiters (ICLs) can help prevent these issues. In this article, TDK Electronics’ Matt Reynolds examines ICLs based on NTC and PTC thermistors, discussing the underlying technology and the device options.

A Look at Cores with TrustZone-M
It’s not so easy to keep up with all the new security features on the latest and greatest embedded processors—especially while you’re busy focusing on the more fundamental and unique aspects of your design. In this article, Colin O’Flynn helps out by examining the new processor cores using TrustZone-M, a feature that helps you secure even low-cost and lower power system designs.

PROJECTS THAT REUSE & RECYCLE

Energy Monitoring Part 2
In Part 1 of this article series, George Novacek began describing an MCU-based system he built to monitor his household energy. Here, he continues that discussion, this time focusing on the electrical power tracking module. As the story shows, he stuck to a design challenge of building the system with as many components he already had in his component bins.

Variable Frequency Drive Part 1
Modern appliances claim to be more efficient, but they’re certainly not designed to last as long as older models. In this project article, Brian Millier describes how he reused subsystems from a defunct modern washing machine to power his bandsaw. The effort provides valuable insights on how to make use of the complete 3-phase Variable Frequency Drive (VFD) borrowed from the washing machine.

FUN PROJECT ARTICLES WITH ALL THE DETAILS

Windless Wind Chimes (Part 2)
In part 1 of this article series, Jeff Bachiochi built a system to simulate breezes randomly playing the sounds of suspended wind chimes. In part 2 the effort evolves into a less random, more orchestrated project. Jeff decided this time to craft a string of chromatically tuned chimes, similar to what an orchestra might use so the project could be used to play music. The project relies on MIDI, an industry standard music technology protocol designed to create and share music and artistic works.

Building a Smart Frying Pan
There’s almost no limit to what an MCU can be used for—-including objects that previously had no electronics at all. In this article, learn how Cornell University graduate Joseph Dwyer build a Microchip PIC32 MCU-based system that wirelessly measures and controls the temperature of a pan on a stove. The system improves both the safety and reliability of cooking on the stove, and has potentially interesting commercial applications.

EOG-Controlled Video Game
There’s much be to learned about how electronics can interact with biological signals—not only to record, but also to see how they can be used as inputs for control applications. With ongoing research in fields such as virtual reality and prosthetics, new systems are being developed to interpret different types of signals for practical applications. Learn how Cornell graduates  Eric Cole, Evan Mok and Alex Huang use electrooculography (EOG) to control a simple video game by measuring eye movement.

Software/Hardware Solution Facilitates IoT System Development

Recon Industrial Controls has announced LabRecon, a software and hardware product that enables users to create rich graphical interfaces for “remote” IoT or “local” measurement and control applications. A drag-and-drop panel builder and graphical programming environment allows one to easily build an interface and create the operating logic for any project. A USB connected “Breadboard Experimentor” circuit board provides the measurement and control link.
The product features a “Measurement Wizard” that lets you choose from a built-in database of over 500 commercially available sensors to automatically configure sensor configurations. The wizard also provides circuits with component values for voltage and current measurements. LabRecon’s “Breadboard Experimentor” incorporates a solder-less breadboard to quickly build interface circuitry to sensors or output devices. The on-board LabRecon chip provides many I/O options including 8 12-bit analog, frequency and digital inputs. Outputs comprise PWM, servo, frequency and stepper motor signals. Pins can also be configured to support 24-bit ADCs, 12 or 16-bit DACs and port expanders. As an alternative to the Breadboard Experimentor, LabRecon chips are available in DIP packages, which provide the same I/O functionality.

The software’s graphical programming feature uses Drag-and-drop functions, which can be wired together, to add analysis and control functionality to a project. Algorithms can be further expanded using the “code link” interface to text-based languages such as Python, Java, C#, Visual Basic and so on. LabRecon also comprises a server to allow access of the created GUI by computers or mobile devices. Furthermore, emails and text messages can be sent periodically or upon events. The server also includes a MQTT broker to allow MQTT clients to share data with the software. Even without Breadboard Experimentor or the LabRecon chip, the software has powerful features that can be used for free. Such features include simulation, the Measurement Wizard and a serial monitor/terminal.

A Kickstarter campaign is underway for the LebRecon product. The Kickstarter link is posted on www.LabRecon.com

Recon Industrial Controls | www.labrecon.com

 

Reference Designs and Analog ICs Target Hybrid and Electric Vehicles

Texas Instruments (TI) has introduced fully tested reference designs for battery management and traction inverter systems, along with new analog circuits with advanced monitoring and protection features to help reduce carbon dioxide emissions and enable hybrid electric vehicles and electric vehicles (HEV/EVs) to drive farther and longer.
Scalable across six to 96-series cell supervision circuits, TI’s new battery management system (BMS) reference design (shown) features the advanced BQ79606A-Q1 precision battery monitor and balancer. Engineers can get their automotive designs to market quickly using the reference design, which implements the battery monitor in a daisy chain configuration to create a highly accurate and reliable system design for three- to 378-series, 12-V up to 1.5 kV lithium-ion battery packs.

The highly integrated BQ79606A-Q1 accurately monitors temperature and voltage levels and helps maximize battery life and time on the road. Additionally, the BQ79606A-Q1 battery monitor features safe-state communication that helps system designers meet requirements up to Automotive Safety Integrity Level D (ASIL D), which is the highest functional safety goal defined by the ISO 26262 road vehicles standard.

With so many kilowatts of power filtering through an electric vehicle’s traction inverter and batteries, high temperatures could potentially damage expensive and sensitive powertrain elements. Excellent thermal management of the system is crucial to vehicle performance, as well as protecting drivers and passengers.

To protect powertrain systems such as a 48-V starter generator from overheating, TI introduced the TMP235-Q1 precision analog output temperature sensors. This low-power, low-quiescent-current (9-µA) device provides high accuracy (±0.5°C typical and ±2.5°C maximum accuracy across the full operating temperature from -40°C to 150°C) to help traction inverter systems react to temperature surges and apply appropriate thermal management techniques.

The TMP235-Q1 temperature sensing device joins the recently released UCC21710-Q1 and UCC21732-Q1 gate drivers in helping designers create smaller, more efficient traction-inverter designs. These devices are the first isolated gate drivers to integrate sensing features for insulated-gate bipolar transistors (IGBTs) and silicon carbide (SiC) field-effect transistors, enabling greater system reliability in applications operating up to 1.5 kVRMS and with superior isolation surge protection exceeding 12.8 kV with a specified isolation voltage of 5.7 kV. The devices also provide fast detection times to protect against overcurrent events while ensuring safe system shutdown.

To power the new gate drivers directly from a car’s 12-V battery, TI has released a new reference design demonstrating three types of IGBT/SiC bias-supply options for traction inverter power stages. The design consists of reverse-polarity protection, electric-transient clamping and over- and under-voltage protection circuits. The compact design includes the new LM5180-Q1, which is a 65-V primary-side regulation flyback converter with a 100-V, 1.5-A integrated power MOSFET.

Texas Instruments | www.ti.com

 

Semtech LoRa Tech Leveraged for Construction and Mining Gear

Semtech has announced that MachineMax, a provider of smart solutions for fleet management, construction and mining applications, has integrated Semtech’s LoRa devices and wireless radio frequency technology (LoRa Technology) into a new smart construction machine usage tracking solution. With Semtech’s LoRa Technology, MachineMax says they were able to create simple, easy to deploy solutions which effectively monitor machine status from anywhere on a construction or mining site.

Machine idling, where a machine’s engine is running but the machine is not actively in use, accounts for an estimated 37% of the time a construction or mining machine is operating on average. Idling results in an increased amount of fuel waste and machine wear, without creating productive machine output. Previously, monitoring the usage status of a mining or construction fleet was accomplished manually, with site managers continually checking on the use status of machines, an expensive and time consuming task.

MachineMax developed a LoRa-based solution which can be easily deployed onto fleet machines in under a minute. The devices attach magnetically and gather real-time data on machine usage status, such as whether or not a machine is idle. With real-time data on when a machine is in use, site managers can make more efficient use of a machine’s time to prevent idling, reducing the amount of fuel used and prolonging machine life.

Semtech’s LoRa devices and wireless radio frequency technology is a widely adopted long-range, low-power solution for IoT that gives telecom companies, IoT application makers and system integrators the feature set necessary to deploy low-cost, interoperable IoT networks, gateways, sensors, module products and IoT services worldwide. IoT networks based on the LoRaWAN specification have been deployed in 100 countries and Semtech is a founding member of the LoRa Alliance.

Semtech | www.semtech.com

 

Tuesday’s Newsletter: IoT Tech Focus

Coming to your inbox tomorrow: Circuit Cellar’s IoT Technology Focus newsletter. Tomorrow’s newsletter covers what’s happening with Internet-of-Things (IoT) technology–-from devices to gateway networks to cloud architectures. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

Bonus: We’ve added Drawings for Free Stuff to our weekly newsletters. Make sure you’ve subscribed to the newsletter so you can participate.

Already a Circuit Cellar Newsletter subscriber? Great!
You’ll get your IoT Technology Focus newsletter issue tomorrow.

Not a Circuit Cellar Newsletter subscriber?
Don’t be left out! Sign up now:

Our weekly Circuit Cellar Newsletter will switch its theme each week, so look for these in upcoming weeks:

Embedded Boards.(5/28) The focus here is on both standard and non-standard embedded computer boards that ease prototyping efforts and let you smoothly scale up to production volumes.

Analog & Power. (6/4) This newsletter content zeros in on the latest developments in analog and power technologies including DC-DC converters, AD-DC converters, power supplies, op amps, batteries and more.

Microcontroller Watch (6/11) This newsletter keeps you up-to-date on latest microcontroller news. In this section, we examine the microcontrollers along with their associated tools and support products.

June Circuit Cellar: Sneak Preview

The June issue of Circuit Cellar magazine is out next week!. We’ve been tending our technology crops to bring you a rich harvest of in-depth embedded electronics articles. We’ll have this 84-page magazine brought to your table very soon..

Not a Circuit Cellar subscriber?  Don’t be left out! Sign up today:

 

Here’s a sneak preview of June 2019 Circuit Cellar:

TOOLS AND CONCEPTS FOR ENGINEERS

Integrated PCB Design Tools
After decades of evolving their PCB design tool software packages, the leading tool vendors have the basics of PCB design nailed down. In recent years, these companies have continued to come up with new enhancements to their tool suites, addressing a myriad of issues related to not just the PCB design itself, but the whole process surrounding it. Circuit Cellar Chief Editor Jeff Child looks at the latest integrated PCB design tool solutions.

dB for Dummies: Decibels Demystified
Understanding decibels—or dB for short—may seem intimidating. Frequent readers of this column know that Robert uses dB terms quite often—particularly when talking about wireless systems or filters. In this article, Robert Lacoste discusses the math underlying decibels using basic concepts. The article also covers how they are used to express values in electronics and even includes a quiz to help you hone your decibel expertise.

Understanding PID
As a means for implementing feedback control systems, PID is an important concept in electronics engineering. In this article, Stuart Ball explains how PID can be applied and explains the concept by focusing on a simple circuit design.

DESIGNING CONNECTED SYSTEMS

Sensor Connectivity Trends
While sensors have always played a key role in embedded systems, the exploding Internet of Things (IoT) phenomenon has pushed sensor technology to the forefront. Any IoT implementation depends on an array of sensors that relay input back to the cloud. Circuit Cellar Chief Editor Jeff Child dives into the latest technology trends and product developments in sensors with an emphasis on their connectivity aspects.

Bluetooth Mesh (Part 3)
In this next part of his article series on Bluetooth mesh, Bob Japenga looks at how to create secure provisioning for a Bluetooth Mesh network without requiring user intervention. He takes a special look at an attack which Bluetooth’s asymmetric key encryption is vulnerable to called Man-in-the-Middle.

PONDERING POWER AND ENERGY

Product Focus: AC-DC Converters
To their peril, embedded system developers often treat their choice of power supply as an afterthought. But choosing the right AC-DC converter is critical to the ensuring your system delivers power efficiently to all parts of your system. This Product Focus section updates readers on these trends and provides a product album of representative AC-DC converter products.

Energy Monitoring (Part 1)
The efficient use of energy is a topic moving ever more front and center these days as climate change and energy costs begin to affect our daily lives. Curious to discover how efficient his own energy consumption was, George Novacek built an MCU-based system to monitor his household energy. And, in order to make sure this new device wasn’t adding more energy use, he chose to make the energy monitoring system solar-powered.

Building a PoE Power Subsystem
Power-over-Ethernet (PoE) allows a single cable to provide both data interconnection and power to devices. In this article, Maxim Integrated’s  and Maxim Integrated’s Thong Huynh and Suhei Dhanani explore the key issues involved in implementing rugged PoE systems. Topics covered include standards compliance, interface controller selection, DC-DC converter choices and more.

Taming Your Wind Turbine
While you can buy off-the-shelf wind power generators these days, they tend to get bad reviews from users. The problem is that harnessing wind energy takes some “taming” of the downstream electronics. In this article, Alexander Pozhitkov discusses his characterization project for a small wind turbine. This provides a guide for designing your own wind energy harvesting system.

MORE PROJECT ARTICLES WITH ALL THE DETAILS

Windless Wind Chimes (Part 1)
Wind chimes make a pleasant sound during the warm months when windows are open. But wouldn’t it be nice to simulate those sounds during the winter months when your windows are shut? In part 1 of this project article, Jeff Bachiochi builds a device that simulates a breeze randomly playing suspended wind chimes. Limited to the standard 5-note pentatonic chimes, this device is based on a Microchip PIC18 low power microcontroller.

GPS Guides Robotic Car
In this project article, Raul Alvarez-Torrico builds a robotic car that navigates to a series of GPS waypoints. Using the Arduino UNO for a controller, the design is aimed at robotics beginners that want to step things up a notch. In the article, Raul discusses the math, programing and electronics hardware choices that went into this project design.

Haptic Feedback Electronic Travel Aid
Time-of-flight sensors have become small and affordable in the last couple years. In this article, learn how Cornell graduates Aaheli Chattopadhyay, Naomi Hess and Jun Ko detail creating a travel aid for the visually impaired with a few time-of-flight sensors, coin vibration motors, an Arduino Pro Mini, a Microchip PIC32 MCU, a flashlight and a sock.

Solar Powered BLE Sensor Platform Offers Battery-Less IoT Solution

ON Semiconductor has introduced its RSL10 Multi-Sensor Platform powered only with a solar cell. This complete solution supports the development of IoT sensors using continuous solar energy harvesting to gather and communicate data through Bluetooth Low Energy (BLE), without the need for batteries or other forms of non-renewable energy.

The combination of ultra-low-power wireless communications, small form-factor solar cell and low duty cycle sensing applications makes it possible to develop and deploy totally maintenance-free IoT sensor nodes. The RSL10 Solar Cell Multi-Sensor Platform is enabled by the RSL10 SIP, a complete System-in-Package (SiP) solution featuring the RSL10 radio, integrated antenna and all passive components.

The platform combines the RSL10 SIP with a solar cell and a host of low power sensors from Bosch Sensortec, including the BME280 all-in-one environmental sensor (pressure, temperature, humidity) and the BMA400 ultra-low-power 3-axis accelerometer. Together, they will allow developers and manufacturers to create complete IoT nodes that are entirely powered through renewable energy or energy harvested from the sensor’s surroundings.

There are a growing number of IoT sensor applications where the duty cycle is low enough to support intermittent communications, allowing the energy needed to support operation to be harvested using renewable sources. The energy efficiency of the RSL10 is augmented by the highly efficient power management system and the ultra-low-power sensors implemented in the platform. Applications are expected to include smart home and building automation such as HVAC control, window/door sensors and air quality monitoring. Asset tracking including package open/close detection, shock monitoring, and temperature and humidity data logging are also possible applications.

For easy development, the platform is supplied with all design files (Gerber, schematic and BoM) and customizable source code as part of a CMSIS software package. The RSL10 Solar Cell Multi-Sensor Platform is available now from ON Semiconductor.

ON Semiconductor | www.onsemi.com

 

Next Newsletter: Automotive Electronics

Coming to your inbox tomorrow: Circuit Cellar’s Automotive Electronics newsletter. April has a 5th Tuesday, so we’re bringing you a bonus newsletter:
Automotive Electronics. Automotive dashboard are evolving into so-called infotainment systems at the same time more of the car is being controlled by embedded  computing. That’s driving a need for powerful MCU-based solutions that support these trends. This newsletter looks at the latest technology trends and product developments in automotive electronics.

Bonus: We’ve added Drawings for Free Stuff to our weekly newsletters. Make sure you’ve subscribed to the newsletter so you can participate.

Already a Circuit Cellar Newsletter subscriber? Great!
You’ll get your
Automotive Electronics newsletter issue tomorrow.

Not a Circuit Cellar Newsletter subscriber?
Don’t be left out! Sign up now:

Our weekly Circuit Cellar Newsletter will switch its theme each week, so look for these in upcoming weeks:

Analog & Power. (5/7) This newsletter content zeros in on the latest developments in analog and power technologies including DC-DC converters, AD-DC converters, power supplies, op amps, batteries and more.

Microcontroller Watch (5/14) This newsletter keeps you up-to-date on latest microcontroller news. In this section, we examine the microcontrollers along with their associated tools and support products.

IoT Technology Focus. (5/21) Covers what’s happening with Internet-of-Things (IoT) technology–-from devices to gateway networks to cloud architectures. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

Embedded Boards.(5/28) The focus here is on both standard and non-standard embedded computer boards that ease prototyping efforts and let you smoothly scale up to production volumes.

Next Newsletter: Embedded Boards

Coming to your inbox tomorrow: Circuit Cellar’s Embedded Boards newsletter. Tomorrow’s newsletter content focuses on both standard and non-standard embedded computer boards that ease prototyping efforts and let you smoothly scale up to production volumes.

Bonus: We’ve added Drawings for Free Stuff to our weekly newsletters. Make sure you’ve subscribed to the newsletter so you can participate.

Already a Circuit Cellar Newsletter subscriber? Great!
You’ll get your
Embedded Boards newsletter issue tomorrow.

Not a Circuit Cellar Newsletter subscriber?
Don’t be left out! Sign up now:

Our weekly Circuit Cellar Newsletter will switch its theme each week, so look for these in upcoming weeks:

April has a 5th Tuesday, so we’re bringing you a bonus newsletter:
Automotive Electronics (4/30)  Automotive dashboard are evolving into so-called infotainment systems at the same time more of the car is being controlled by embedded  computing. That’s driving a need for powerful MCU-based solutions that support these trends. This newsletter looks at the latest technology trends and product developments in automotive electronics.

Analog & Power. (5/7) This newsletter content zeros in on the latest developments in analog and power technologies including DC-DC converters, AD-DC converters, power supplies, op amps, batteries and more.

Microcontroller Watch (5/14) This newsletter keeps you up-to-date on latest microcontroller news. In this section, we examine the microcontrollers along with their associated tools and support products.

IoT Technology Focus. (5/21) Covers what’s happening with Internet-of-Things (IoT) technology–-from devices to gateway networks to cloud architectures. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

May Circuit Cellar: Sneak Preview

The May issue of Circuit Cellar magazine is out next week!. We’ve been hard at work laying the foundation and nailing the beams together with a sturdy selection of  embedded electronics articles just for you. We’ll soon be inviting you inside this 84-page magazine.

Not a Circuit Cellar subscriber?  Don’t be left out! Sign up today:

 

Here’s a sneak preview of May 2019 Circuit Cellar:

EMBEDDED COMPUTING AT WORK

Technologies for Digital Signage
Digital signage ranks among the most dynamic areas of today’s embedded computing space. Makers of digital signage players, board-level products and other technologies continue to roll out new solutions for implementing powerful digital signage systems. Circuit Cellar Chief Editor Jeff Child looks at the latest technology trends and product developments in digital signage.

PC/104 and PC/104 Family Boards
PC/104 has come a long way since its inception over 25 ago. With its roots in ISA-bus PC technology, PC/104 evolved through the era of PCI and PCI Express by spinning off its wider family of follow on versions including PC/104-Plus, PCI-104, PCIe/104 and PCI/104-Express. This Product Focus section updates readers on these technology trends and provides a product gallery of representative PC/104 and PC/104-family boards.

TOOLS & TECHNIQUES FOR EMBEDDED ENGINEERING

Code Analysis Tools
Today it’s not uncommon for embedded devices to have millions of lines of software code. Code analysis tools have kept pace with these demands making it easier for embedded developers to analyze, debug and verify complex embedded software. Circuit Cellar Chief Editor Jeff Child explores the latest technology trends and product developments in code analysis tools.

Transistor Basics
In this day and age of highly integrated ICs, what is the relevance of the lone, discrete transistor? It’s true that most embedded systems can be solved by chip level solutions. But electronic component vendors do still make and sell individual transistors because there’s still a market for them. In this article, Stuart Ball reviews some important basics about transistors and how you can use them in your embedded system design.

Pressure Sensors
Over the years, George Novacek has done articles examining numerous types of sensors that measure various physical aspects of our world. But one measurement type he’s not yet discussed in the past is pressure. Here, George looks at pressure sensors in the context of using them in an electronic monitoring or control system. The story looks at the math, physics and technology associated with pressure sensors.

MICROCONTROLLERS DO IT ALL

Robotic Arm Plays Beer Pong
Simulating human body motion is a key concept in robotics development. With that in mind, learn how these Cornell graduates Daniel Fayad, Justin Choi and Harrison Hyundong Chang accurately simulate the movement of a human arm on a small-sized robotic arm. The Microchip PIC32 MCU-based system enables the motion-controlled, 3-DoF robotic arm to take a user’s throwing motion as a reference to its own throw. In this way, they created a robotic arm that can throw a ping pong ball and thus play beer pong.

Fancy Filtering with the Teensy 3.6
Signal filtering entails some tricky tradeoffs. A fast MCU that provides hardware-based floating-point capability eases some of those tradeoffs. In the past, Brian Millier has used the Arm-based Teensy MCU modules to serve meet those needs. In this article, Brian taps the Teensy 3.6 Arm MCU module to perform real-time audio FFT-convolution filtering.

Real-Time Stock Monitoring Using an MCU
With today’s technology, even very simple microcontroller-based devices can fetch and display data from the Internet. Learn how Cornell graduates David Valley and Saelig Khatta built a system using that can track stock prices in real-time and display them conveniently on an LCD screen. For the design, they used an Espressif Systems ESP8266 Wi-Fi module controlled by a Microchip PIC32 MCU. Our fun little device fetches chosen stock prices in real-time and displays them on a screen.

… AND MORE FROM OUR EXPERT COLUMNISTS

Attacking USB Gear with EMFI
Many products use USB, but have you ever considered there may be a critical security vulnerability lurking in your USB stack? In this article, Colin O’Flynn walks you through on example product that could be broken using electromagnetic fault injection (EMFI) to perform this attack without even removing the device enclosure.

An Itty Bitty Education
There’s no doubt that we’re living in a golden age when it comes to easily available and affordable development kits for fun and education. With that in mind, Jeff Bachiochi shares his experiences programming and playing with the Itty Bitty Buggy from Microduino. Using the product, you can build combine LEGO-compatible building blocks into mobile robots controlled via Bluetooth using your cellphone.

Tuesday’s Newsletter: IoT Tech Focus

Coming to your inbox tomorrow: Circuit Cellar’s IoT Technology Focus newsletter. Tomorrow’s newsletter covers what’s happening with Internet-of-Things (IoT) technology–-from devices to gateway networks to cloud architectures. This newsletter tackles news and trends about the products and technologies needed to build IoT implementations and devices.

Bonus: We’ve added Drawings for Free Stuff to our weekly newsletters. Make sure you’ve subscribed to the newsletter so you can participate.

Already a Circuit Cellar Newsletter subscriber? Great!
You’ll get your IoT Technology Focus newsletter issue tomorrow.

Not a Circuit Cellar Newsletter subscriber?
Don’t be left out! Sign up now:

Our weekly Circuit Cellar Newsletter will switch its theme each week, so look for these in upcoming weeks:

Embedded Boards.(4/23) The focus here is on both standard and non-standard embedded computer boards that ease prototyping efforts and let you smoothly scale up to production volumes.

April has a 5th Tuesday, so we’re bringing you a bonus newsletter:
Automotive Electronics (4/30)  Automotive dashboard are evolving into so-called infotainment systems at the same time more of the car is being controlled by embedded  computing. That’s driving a need for powerful MCU-based solutions that support these trends. This newsletter looks at the latest technology trends and product developments in automotive electronics.

Analog & Power. (5/7) This newsletter content zeros in on the latest developments in analog and power technologies including DC-DC converters, AD-DC converters, power supplies, op amps, batteries and more.

Microcontroller Watch (5/14) This newsletter keeps you up-to-date on latest microcontroller news. In this section, we examine the microcontrollers along with their associated tools and support products.

Rugged IoT Gateways are Based on i.MX6 and Raspberry Pi

Kontron has announced two new industrial computers, the KBox A-330-RPI and KBox A-330-MX6, specifically designed for cost-sensitive control and gateway applications. The KBox A-330-RPI is based on the long-term available Raspberry Pi Compute Module CM3+ and can therefore use the huge software pool of the Raspberry Pi community. Equipped with a Broadcom BCM2837 Quad Core Arm processor, the KBox A-330-RPI is compatible with the established Raspberry Pi standards and has been enhanced with industrial features.

The new KBox A-330-MX6 differs from the KBox A-330-RPI primarily by the Dual Core i.MX6 processor from NXP, which is, like the Raspberry Pi Compute Module CM3+, long term available. In addition, the variant based on the NXP processor optionally offers additional industrial protocol stacks such as EtherCAT, PROFINET, Modbus and CANopen to enable customers to easily integrate control software.

Both KBox A-330 variants operate fanless and are designed for industrial control and gateway tasks in control cabinets due to their slim design and the possibility of DIN rail mounting. Two Fast Ethernet ports, RS232, RS485 or CAN and four I/O ports are available as interfaces. A powerful user interface can be operated during commissioning or in the target application via two USB channels and an HDMI connection.

With the KBox A-330 family Kontron offers an industrial grade platform that enables connection to various communication levels, serves as a gateway for IoT applications and can integrate sensors and actuators. As operating system Kontron offers Yocto Linux for the KBox A-330-MX6 and Raspbian for the KBox A-330-RPI. On a project basis, applications are realizable that include advanced security features such as secure authentication and data encryption that go beyond normal security requirements.

In conjunction with the modular IoT software framework SUSiEtec from Kontron’s sister company S&T Technologies, any applications and cloud solutions on the market—from sensors to edge computers to private or public clouds—can also be connected and supported to develop IoT applications or establish new business models.

Kontron | www.kontron.com

IoT Monitoring System for Commercial Fridges

Using LoRa Technology

IoT implementations can take many shapes and forms. Learn how these four Camosun College students developed a system to monitor all the refrigeration units in a commercial kitchen simultaneously. The system uses Microchip PIC MCU-based monitoring units and wireless communication leveraging the LoRa wireless protocol.

By Tyler Canton, Akio Yasu, Trevor Ford and Luke Vinden

In 2017, the commercial food service industry created an estimated 14.6 million wet tons of food in the United States [1]. The second leading cause of food waste in commercial food service, next to overproduction, is product loss due to defects in product quality and/or equipment failure [2].

While one of our team members was working as the chef of a hotel in Vancouver, more than once he’d arrive at work to find that the hotel’s refrigeration equipment had failed overnight or over the weekend, and that thousands of dollars of food had become unusable due to being stored at unsafe temperatures. He always saw this as an unnecessary loss—especially because the establishment had multiple refrigeration units and ample space to move product around. In this IoT age, this is clearly a preventable problem.

For our Electronics & Computer Engineering Technologist Capstone project, we set forth to design a commercial refrigeration monitoring system that would concurrently monitor all the units in an establishment, and alert the chefs or managers when their product was not being stored safely. This system would also allow the chef to check in on his/her product at any time for peace of mind (Figure 1).

Figure 1
This was the first picture we took of our finished project assembled. This SLA printed enclosure houses our 10.1″ LCD screen, a Raspberry Pi Model 3B and custom designed PCB.

We began with some simple range testing using RFM95W LoRa modules from RF Solutions, to see if we could reliably transmit data from inside a steel box (a refrigerator), up several flights of stairs, through concrete walls, with electrical noise and the most disruptive interference: hollering chefs. It is common for commercial kitchens to feel like a cellular blackout zone, so reliable communication would be essential to our system’s success.

System Overview

We designed our main unit to be powered and controlled by a Raspberry Pi 3B (RPi) board. The RPi communicates with an RFM95W LoRa transceiver using Serial Peripheral Interface (SPI). This unit receives temperature data from our satellite units, and displays the temperatures on a 10.1″ LCD screen from Waveshare. A block diagram of the system is shown in Figure 2. We decided to go with Node-RED flow-based programming tool to design our GUI. This main unit is also responsible for logging the data online to a Google Form. We also used Node-RED’s “email” nodes to alert the users when their product is stored at unsafe temperatures. In the future, we plan to design an app that can notify the user via push notifications. This is not the ideal system for the type of user that at any time has 1,000+ emails in their inbox, but for our target user who won’t allow more than 3 or 4 to pile up it has worked fine.

Figure 2
The main unit can receive temperature data from as many satellite units as required. Data are stored locally on the Raspberry Pi 3B, displayed using a GUI designed by Node-RED and logged online via Google Sheets.

We designed an individual prototype (Figure 3) for each satellite monitoring unit, to measure the equipment’s temperature and periodically transmit the data to a centralized main unit through LoRa communication. The units were intended to operate at least a year on a single battery charge. These satellites, controlled by a Microchip Technology PIC24FJ64GA704 microcontroller (MCU), were designed with an internal Maxim Integrated DS18B20 digital sensor (TO-92 package) and an optional external Maxim

Figure 3
This enclosure houses the electronics responsible for monitoring the temperatures and transmitting to the main unit. These were 3D printed on Ultimaker 3 printers.

Integrated DS18B20 (waterproof stainless steel tube package) to measure the temperature using the serial 1-Wire interface.

Hardware

All our boards were designed using Altium Designer 2017 and manufactured by JLCPCB. We highly recommend JLCPCB for PCB manufacturing. On a Tuesday we submitted our order to the website, and the finished PCB’s were manufactured, shipped, and delivered within a week. We were amazed by the turnaround time and the quality of the boards we received for the price ($2 USD / 10 PCB).

Figure 4
The main unit PCB’s role is simply to allow the devices to communicate with each other. This includes the RFM95W LoRa transceivers, RPi, LCD screen and a small fan

Main Unit Hardware: As shown in Figure 4, our main board’s purpose is communicating with the RPi and the LCD. We first had to select an LCD display for the main unit. This was an important decision, as it was the primary human interface device (HID) between the system and its user. We wanted a display that was around 10″—a good compromise between physical size and readability. Shortly after beginning our search, we learned that displays between 7″ and 19″ are not only significantly more difficult to come by, but also significantly more expensive. Thankfully, we managed to source a 10.1″ display that met our budget from robotshop.com. On the back of the display was a set of female header pins designed to interface with the first 26 pins of the RPi’s GPIO pins. The only problem with the display was that we needed access to those same GPIO pins to interface with the rest of our peripherals.

Figure 5
Our main board, labeled Mr. Therm, was designed to attach directly to the LCD screen headers. RPi pins 1-26 share the same connectivity as the main board and the LCD.

We initially planned on fixing this problem by placing our circuit board between the RPi and the display, creating a three-board-stack. Upon delivery and initial inspection of the display, however, we noticed an undocumented footprint that was connected to all the same nets directly beneath the female headers. We quickly decided to abandon the idea of the three-board-stack and decided instead to connect our main board to that unused footprint in the same way the RPi connects to display (Figure 5). This enabled us to interface all three boards, while maintaining a relatively thin profile. The main board connects four separate components to the rest of the circuit. It connects the RFM95W transceiver to the RPi, front panel buttons, power supply and a small fan.

Read the full article in the April 345 issue of Circuit Cellar
(Full article word count: 3378 words; Figure count: 11 Figures.)

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