Obsolescence-Proof Your UI (Part 1)

(Photo 1)
Web Server Strategy

After years of frustration dealing with graphical user interface technologies that go obsolete, Steve decided that web browser technology could help this problem. With that in mind, he built a web server that could perform common operations that he needed on the IEEE-488 bus—and it is basically obsolescence-proof.

By Steve Hendrix

My consulting business is designing custom embedded electronics. Many such systems are size-constrained, but still need some type of user interface. For portable devices, the battery is usually the biggest point of discussion. For wireless designs, it’s the antenna. But for virtually every design, the user interface figures prominently in the concept discussions.

I’ve been involved with one particular design for some 20 years now. When I took it over from the client’s in-house designer, the internal structure was very shaky. Unfortunately, they were not willing to change it due to the re-certification efforts that would be required for a major change. The design’s user interface used a graphic LCD with a touchscreen overlay. I have just completed the latest revision to replace an obsolete part—the latest in a long series of revisions caused by the display panel or the touchscreen going obsolete. This usually happens just about the time the whole product gets through final certification. In this case, we jumped through a lot of hoops to avoid disturbing the core of the product so we wouldn’t require a a big recertification effort. We did so by building a daughterboard that emulates the original touchscreen. A web browser interface would be so much easier!

In a similar vein, I recently purchased a spectrum analyzer to replace a failed unit. The only way to get a screen dump into my PC is via the IEEE-488 bus. That standard is sometimes known as GPIB (General Purpose Interface Bus) or HPIB (Hewlett-Packard Interface Bus). Because this bus has mostly fallen out of favor, instruments that use it are inexpensive. The solutions that purport to interface the IEEE-488 bus to a PC are themselves badly dated. In addition to requiring a cable big enough to flip an instrument off the bench, several other pieces are needed. You need to buy a board that goes inside the PC for four figures, and software to run it for well up into four figures, and hope your PC and operating system are old enough to be compatible. Alternatively, numerous USB interfaces are available. All of those interfaces require a custom driver in your PC, and most of those drivers require older versions of Windows.

Photo 2
(a) A close-up view of the finished unit, which fits comfortably within a standard IEEE-488 connector backshell. This unit is ready for the final application of the label showing its permanently-assigned MAC address. (b) A peek under the hood, showing the microcontroller, the IEEE-488 bus termination resistor packs, and most of the power supply. The mini-USB connector makes no data connection, but only provides power to the unit. Such power supplies have become such ubiquitous commodity products that they are the most cost-effective way to get 5 V power to the unit.Many years ago, I worked for a company who specialized in IEEE-488 interfaces. Although I’d forgotten some of the nuances that make it such a pain to work with directly, I remembered enough to know that the Microchip PIC18F97J60 microcontroller could directly drive the bus lines for a single instrument. The PIC would need buffering to deal with the full 14 instruments that can be on the bus per the specification, but I just wanted to interface a single instrument. Best of all, I already had experience with building a web server in this chip from my solar power controller discussed in the July 2014 and August 2014 issues (Circuit Cellar 288 and Circuit Cellar 289.) The microcontroller and all required electronics could fit inside the backshell of a standard IEEE-488 connector. The lead article photo (Photo 1) shows the very tidy end result—note the MAC addresses printed on each label. Photo 2 shows a close-up view of the exterior and interior.

I’m sure that HTTP and web browsers will someday go the way of buggy whips. However, given their use today in everything from PCs to laptops to tablets to smart phones, I’m thinking web browsers are likely to be around for a while. With that in mind, I chose to build a web server that could perform common operations that I need on the IEEE-488 bus, and ultimately built it into a product available for sale to others with similar needs. By using a web browse the user interface, the device is accessible via anything from a desktop computer to an iPod—and it’s pretty much obsolescence -proof, at least within my lifetime! …

Author′s Note: I offer a special discount on KISS-488 to Circuit Cellar readers. Contact me at SteveHx@HxEngineering.com for details!

Read the full article in the April 333 issue of Circuit Cellar

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NAVIGATING THE INTERNET-OF-THINGS

IoT: From Gateway to Cloud
In this follow on to our March “IoT: Device to Gateway” feature, this time we look at technologies and solutions for the gateway to cloud side of IoT.  Circuit Cellar Chief Editor Jeff Child examines the tools and services available to get a cloud-connected IoT implementation up and running.

Texting and IoT Embedded Devices (Part 2)
In Part 1, Jeff Bachiochi laid the groundwork for describing a project involving texting. He puts that into action this, showing how to create messages on his Espressif System’s ESP8266EX-based device to be sent to an email account and end up with those messages going as texts to a cell phone.

Internet of Things Security (Part 2)
In this next part of his article series on IoT security, Bob Japenga takes a look at side-channel attacks. What are they? How much of a threat are they? And how can we prevent them?

Product Focus: 32-Bit Microcontrollers
As the workhorse of today’s embedded systems, 32-bit microcontrollers serve a wide variety of embedded applications—including the IoT. This Product Focus section updates readers on these trends and provides a product album of representative 32-bit MCU products.

GRAPHICS, VISION AND DISPLAYS

Graphics, Video and Displays
Thanks to advances in displays and innovations in graphics ICs, embedded systems can now routinely feature sophisticated graphical user interfaces. Circuit Cellar Chief Editor Jeff Child dives into the latest technology trends and product developments in graphics, video and displays.

Color Recognition and Segmentation in Real-time
Vision systems used to require big, multi-board systems—but not anymore. Learn how two Cornell undergraduates designed a hardware/software system that accelerates vision-based object recognition and tracking using an FPGA SoC. They made a min manufacturing line to demonstrate how their system can accurately track and categorize manufactured candies carried along a conveyor belt.

SPECIFICATIONS, QUALIFICATIONS AND MORE

Component tolerance
We perhaps take for granted sometimes that the tolerances of our electronic components fit the needs of our designs. In this article, Robert Lacoste takes a deep look into the subject of tolerances, using the simple resistor as an example. He goes through the math to help you better understand accuracy and drift along with other factors.

Understanding the Temperature Coefficient of Resistance
Temperature coefficient of resistance (TCR) is the calculation of a relative change of resistance per degree of temperature change. Even though it’s an important spec, different resistor manufacturers use different methods for defining TCR. In this article, Molly Bakewell Chamberlin examines TCR and its “best practice” interpretations using Vishay Precision Group’s vast experience in high-precision resistors.

Designing of Complex Systems
While some commercial software gets away without much qualification during development, the situation is very different when safety in involved. For aircraft, vehicles or any complex system where failure unacceptable, this means adhering to established standards throughout the development life cycle. In this article, George Novacek tackles these issues and examines some of these standards namely ARP4754.

AND MORE IN-DEPTH PROJECT ARTICLES

Build a Marginal Oscillator Proximity Switch
A damped or marginal oscillator will switch off when energy is siphoned from its resonant LC tank circuit. In his article, Dev Gualtieri presents a simple marginal oscillator that detects proximity to a small steel screw or steel plate. It lights an LED, and the LED can be part of an optically-isolated solid-state relay.

Obsolescence-Proof Your UI (Part 1)
After years of frustration dealing with graphical interface technologies that go obsolete, Steve Hendrix decided there must be a better way. Knowing that web browser technology is likely to be with us for a long while, he chose to build a web server that could perform common operations that he needed on the IEEE-488 bus. He then built it as a product available for sale to others—and it is basically obsolescence-proof.

 

 

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TECHNOLOGY FOR THE INTERNET-OF-THINGS

IoT: From Device to Gateway
The Internet of Things (IoT) is one of the most dynamic areas of embedded systems design today. This feature focuses on the technologies and products from edge IoT devices up to IoT gateways. Circuit Cellar Chief Editor Jeff Child examines the wireless technologies, sensors, edge devices and IoT gateway technologies at the center of this phenomenon.

Texting and IoT Embedded Devices
Texting has become a huge part of our daily lives. But can texting be leveraged for use in IoT Wi-Fi devices? Jeff Bachiochi lays the groundwork for describing a project that will involve texting. In this part, he gets into out the details for getting started with a look at Espressif System’s ESP8266EX SoC.

Exploring the ESP32’s Peripheral Blocks
What makes an embedded processor suitable as an IoT or home control device? Wi-Fi support is just part of the picture. Brian Millier has done some Wi-Fi projects using the ESP32, so here he shares his insights about the peripherals on the ESP32 and why they’re so powerful.

MICROCONTROLLERS HERE, THERE & EVERYWHERE

Designing a Home Cleaning Robot (Part 4)
In this final part of his four-part article series about building a home cleaning robot, Nishant Mittal discusses the firmware part of the system and gets into the system’s actual operation. The robot is based on Cypress Semiconductor’s PSoC microcontroller.

Apartment Entry System Uses PIC32
Learn how a Cornell undergraduate built a system that enables an apartment resident to enter when keys are lost or to grant access to a guest when there’s no one home. The system consists of a microphone connected to a Microchip PIC32 MCU that controls a push solenoid to actuate the unlock button.

Posture Corrector Leverages Bluetooth
Learn how these Cornell students built a posture corrector that helps remind you to sit up straight. Using vibration and visual cues, this wearable device is paired with a phone app and makes use of Bluetooth and Microchip PIC32 technology.

INTERACTING WITH THE ANALOG WORLD

Product Focus: ADCs and DACs
Makers of analog ICs are constantly evolving their DAC and ADC chips pushing the barriers of resolution and speeds. This new Product Focus section updates readers on this technology and provides a product album of representative ADC and DAC products.

Stepper Motor Waveforms
Using inexpensive microcontrollers, motor drivers, stepper motors and other hardware, columnist Ed Nisley built himself a Computer Numeric Control (CNC) machines. In this article Ed examines how the CNC’s stepper motors perform, then pushes one well beyond its normal limits.

Measuring Acceleration
Sensors are a fundamental part of what make smart machines smart. And accelerometers are one of the most important of these. In this article, George Novacek examines the principles behind accelerometers and how the technology works.

SOFTWARE TOOLS AND PROTOTYPING

Trace and Code Coverage Tools
Today it’s not uncommon for embedded devices to have millions of lines of software code. Trace and code coverage 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 trace and code coverage tools.

Manual Pick-n-Place Assembly Helper
Prototyping embedded systems is an important part of the development cycle. In this article, Colin O’Flynn presents an open-source tool that helps you assemble prototype devices by making the placement process even easier.

Money Sorting Machines (Part 3)

Bill Validation

In this final article of his money sorting machine series, Jeff wraps up his coin sorting project and examines how a bill validator can tell one bill’s denomination from another.

By Jeff Bachiochi

Most of us connect Ben Franklin with kites and lightning. He was also a printer and might be best known for Poor Richard’s Almanack—a yearly publication that he published from 1732 to 1758 under the pseudonym of Richard Saunders. It was a best-seller and thanks to his wit and wisdom, his portrait was added to the cover of The Old Farmer’s Almanac in 1851—appearing opposite the founder Robert B. Thomas. It remains there today.

As a master printer and engraver, in 1730 Franklin began printing all paper money issued by Pennsylvania, New Jersey and Delaware. Paper money was first introduced in the region in 1723, but it remained a hot political issue. That’s because it helped farmers and tradesmen, while merchants and landowners wanted it eliminated or limited in its circulation. Paper money printed from ordinary type was easy to counterfeit, but Ben’s ingenuity solved that problem by printing pictures of leaves on every piece of money. Counterfeiters could not duplicate—or even imitate—the fine lines and irregular patterns. The process by which he made the printing plates was secret, but were probably cast in type metal from molds made by pressing leaves into plaster of Paris. There began the Feds vigilant effort to thwart counterfeiters.

Today every aspect of our paper currency is controlled—from its design to its printing, as well as its monitoring and destruction. The paper (which is not paper) and ink (multiple types and formulas) are fabricated for the express use by the Department of Engraving. That department is the Treasury bureau responsible for paper money—as opposed to the U.S Mint, which is the Treasury bureau responsible for coinage. US currency consists of 25% linen and 75% cotton and contains small randomly disbursed red and blue security fibers embedded throughout the material. Depending on the denomination the material is further enhanced by embedding security threads, ribbons and watermarks. Since 1996, printing with colored and color changing inks make the new currency pop. While older black and green currency is rather drab in comparison, it is still legal tender and remains the target of most counterfeiters.

The previous two parts of this article series (December 329 and January 330) centered around coinage. Before we look at bill validation for paper money, I need to finish up with that project. I had purchased a few Coin Acceptors and showed how they are used to identify coinage, especially but not limited to US coins. The acceptance and dispensing of money is presently used in many ways today, including vending machines and ATMs. The discussion also included National Automatic Merchandising Association (NAMA), the organization that developed the international specification for the Multi-Drop Bus/ Internal Communication Protocol (MDB/CP) released in July 2010. The MDB/ICP enables communication between a master controller and any of the peripheral hardware like Coin Acceptors and bill validators. By adhering to these guidelines, any manufacturer’s equipment is interchangeable.

Turns out the Coin Acceptors I purchased don’t have the MDB interface necessary to communicate with a Vending Machine Controller (VMC). I reviewed the protocol and VMC/Peripheral Communication Specifications required by the Coin Acceptor/Changer peripheral and began work on developing an MDB interface that would bridge my Coin Acceptor with the multi-drop bus. 

Read the full article in the February 331 issue of Circuit Cellar

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                                     IMPROVING EMBEDDED SYSTEM DESIGNS

Special Feature: Powering Commercial Drones
The amount of power a commercial drone can draw on has a direct effect on how long it can stay flying as well as on what tasks it can perform. Circuit Cellar Chief Editor Jeff Child examines solar cells, fuel cells and other technology options for powering commercial drones.

CC 330 CoverFPGA Design: A Fresh Take
Although FPGAs are well established technology, many embedded systems developers—particularly those used the microcontroller realm—have never used them before. In this article, Faiz Rahman takes a fresh look a FPGAs for those new to designing them into their embedded systems.

Product Focus: COM Express boards
COM Express boards provide a complete computing core that can be upgraded when needed, leaving the application-specific I/O on the baseboard. This brand new Product Focus section updates readers on this technology and provides a product album of representative COM Express products.

TESTING, TESTING, 1, 2, 3

LF Resonator Filter
In Ed Nisley’s November column he described how an Arduino-based tester automatically measures a resonator’s frequency response to produce data defining its electrical parameters. This time he examines the resultsand explains a tester modification to measure the resonator’s response with a variable series capacitance.

Technology Spotlight: 5G Technology and Testing
The technologies that are enabling 5G communications are creating new challenges for embedded system developers. Circuit Cellar Chief Editor Jeff Child explores the latest digital and analog ICs aimed at 5G and at the test equipment designed to work with 5G technology.

                                     MICROCONTROLLERS IN EVERYTHING

MCU-based Platform Stabilizer
Using an Inertial Measurement Unit (IMU), two 180-degree rotation servos and a Microchip PCI MCU, three Cornell students implemented a microcontroller-based platform stabilizer. Learn how they used a pre-programmed sensor fusion algorithm and I2C to get the most out of their design.

Designing a Home Cleaning Robot (Part 2)
Continuing on with this four-part article series about building a home cleaning robot, Nishant Mittal this time discusses the mechanical aspect of the design. The robot is based on Cypress Semiconductor’s PSoC microcontroller.

Massage Vest Uses PIC32 MCU
Microcontrollers are being used for all kinds of things these days. Learn how three Cornell graduates designed a low-cost massage vest that pairs seamlessly with a custom iOS app. Using the Microchip PIC32 for its brains, the massage vest has sixteen vibration motors that the user can control to create the best massage possible.

AND MORE FROM OUR EXPERT COLUMNISTS:

Five Fault Injection Attacks
Colin O’Flynn returns to the topic of fault injection security attacks. To kick off 2018, he summarizes information about five different fault injection attack stories from 2017—attacks you should be thinking about as an embedded designer.

Money Sorting Machines (Part 2)
In part 1, Jeff Bachiochi delved into the interesting world of money sort machines and their evolution. In part 2, he discusses more details about his coin sorting project. He then looks at a typical bill validator implementation used in vending systems.

Overstress Protection
Last month George Novacek reviewed the causes and results of electrical overstress (EOS). Picking up where that left off, in this article he looks at how to prevent EOS/ESD induced damage—starting with choosing properly rated components.

December Circuit Cellar: A Sneak Preview

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MICROCONTROLLERS IN MOTION

Special Feature: Electronics for Wearable Devices
Circuit Cellar Chief Editor Jeff Child examines how today’s microcontrollers, sensors and power electronics enable today’s wearable products.

329 Cover Screen CapSimulating a Hammond Tonewheel Organ
(Part 2)

Brian Millier continues this two-part series about simulating the Hammond tonewheel organ using a microcontrollers and DACs. This time he examines a Leslie speaker emulation.

Money Sorting Machines (Part 1)
In this new article series, Jeff Bachiochi looks the science, mechanics and electronics that are key to sorting everything from coins to paper money. This month he discusses a project that uses microcontroller technology to sort coins.

Designing a Home Cleaning Robot (Part 1)
This four-part article series about building a home cleaning robot starts with Nishant Mittal discussing his motivations behind to his design concept, some market analysis and the materials needed.

SPECIAL SECTION: GRAPHICS AND VISION

Designing High Performance GUI
It’s critical to understand the types of performance problems a typical end-user might encounter and the performance metrics relevant to user interface (UI) design. Phil Brumby of Mentor’s Embedded Systems Division examines these and other important UI design challenges.

Building a Robotic Candy Sorter
Learn how a pair of Cornell graduates designed and constructed a robotic candy sort. It includes a three degree of freedom robot arm and a vision system using a Microchip PIC32 and Raspberry Pi module.

Raster Laser Projector Uses FPGA
Two Cornell graduates describe a raster laser projector they designed that’s able to project images in 320 x 240 in monochrome red. The laser’s brightness and mirrors positions are controlled by an FPGA and analog circuitry.

ELECTRICITY UNDER CONTROL

Technology Spotlight: Power-over-Ethernet Solutions
Power-over-Ethernet (PoE) enables the delivery of electric power alongside data on twisted pair Ethernet cabling. Chief Editor Jeff Child explores the latest chips, modules and other gear for building PoE systems.

Component Overstress
When an electronic component starts to work improperly, Two likely culprits are electrical overstress (EOS) and electrostatic discharge (ESD). In his article, George Novacek breaks down the important differences between the two and how to avoid their effects.

AND MORE FROM OUR EXPERT COLUMNISTS:

Writing the Proposal
In this conclusion to his “Building an Embedded Systems Consulting Company” article series, Bob Japenga takes a detailed look at how to craft a Statement of Work (SOW) that will lead to success and provide clarity for all stakeholders.

Information Theory in a Nutshell
Claude Shannon is credited as one of the pioneers of computer science thanks to his work on Information Theory, informing how data flows in electronic systems. In this article, Robert Lacoste provides a useful exploration of Information Theory in an easily digestible way.

Two Controller Families Add eSPI Bus

Microchip Technology has made available its MEC17XX and MEC14XX families of embedded controllers with enhanced Serial Peripheral Interface (eSPI). The eSPI bus is the host interface supported by the latest PC computing chip sets and is required for new, upcoming computing applications. The MEC17XX family is based on an ARM Cortex-M4F core and has advanced hardware-accelerated cryptography algorithms to efficiently support the secure boot of a computer. The family offers several additional features including two UARTS and an extended industrial operating temperature range that make the family ideal for industrial computing. In addition, Microchip’s popular MIPS-based MEC14XX family has been expanded to include functionality for supporting the new eSPI Slave Attached Flash (SAF) feature, which allows the Microchip embedded controller to be 37288858386_29fa55a67f_kdirectly connected to an SPI Flash memory using an on-board master controller.

These new embedded controllers are part of an expanded family of devices that have been an integral part in the computing industry’s transition from LPC to eSPI.  The MEC17XX adds security through cryptography functionality to advance secure boot, a security feature developed to ensure a system boots only from software that is trusted by the manufacturer. Furthermore, the addition of two UARTS and support for industrial temperature is necessary for industrial computing applications.

The latest members of the MEC14XX family add a new level of design functionality for computing engineers by adding SAF, which is an optimal solution for USB Type-C power delivery. The latest MEC1428 devices are pin and register compatible with the MEC140X and MEC141X families, which allows designers to easily add eSPI and additional features and have more flexibility in their designs. Both families retain eSPI Master Attached Flash (MAF) capability. All of Microchip’s computing embedded controllers are supported by a variety of development and debug tools and evaluation boards, plus datasheets and other documentation.

The eSPI interface has numerous benefits including allowing for multiple input/output signals to be configured to support either 3.3 V or 1.8 V, which reduces the system cost by eliminating the need for external voltage translators.  These features allow for seamless migration of intellectual property (IP) across multiple x86 computing platforms including those based on Intel’s Atom processors, Intel’s iCore processors and Ryzen processors from AMD.

The four-part MEC17XX family is available in a variety of WFBGA package options, starting at $2.59 each in 10,000 unit quantities. The family features industrial-qualified parts as well as the option of additional EEPROM memory. The MEC1428 is available today in a variety of package options, starting at $2.16 each in 10,000 unit quantities.

Microchip Technology | www.microchip.com

November Circuit Cellar: A Sneak Preview

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TECHNOLOGY IN A CONNECTED WORLD

IoT Gateway Advances Take Diverse Paths: Flexible Networked Solutions
The Internet-of-Things (IoT) phenomenon offers huge opportunities. Circuit Cellar Chief Editor Jeff Child explores how IoT gateways play a vital role in those systems by providing Nov 328 coverbidirectional communication between the devices in the field and the cloud.

Power Analysis Attack on RSA: Asymmetric Adventures
Colin O’Flynn has done a number of great columns about cryptography—in particular symmetric cryptography. This time he’s tackling an asymmetric algorithm: a RSA implementation. Colin describes what’s unique about an RSA cryptosystem and takes us through a power analysis attack.

FOCUS ON ANALOG

Analog Solutions Fuel Industrial System Needs: Connectivity, Control and IIoT
Whether it’s connecting with analog sensors or driving actuators, analog ICs play many critical roles in industrial applications. Here, Circuit Cellar Chief Editor Jeff Child examines the latest analog technologies and products serving the needs of today’s industrial systems.

Using Power Audio Amplifiers in Untypical Ways (Part 2): More Alternative Uses
In Part 1 Petre Petrov described many interesting ways to use power audio amplifiers (PAAs) as universal building blocks similar to the op amps and comparators. Here, he discusses several more things that can be built from PAAs including wave generators and transformer drivers.

SPOTLIGHT ON MONITORING AND TESTING

Gas Monitoring and Sensing (Part 2): Putting the Sensor to Work
Columnist Jeff Bachiochi continues his exploration of gas monitoring and sensing. This time he discusses some of the inexpensive sensors available that can be applied to this application. Jeff then tackles the factors to consider when calibrating these sensors and how to use them effectively.

Logger Device Tracks Amp Hours (Part 2): Alternative Energy Sources
n this follow on to Part 1 of his story, William Wachsmann describes putting to use the amp-hour logger he built using a microcontroller and a clamp-on ammeter. This time he discusses modifying the amp-hour software so it can be used as an analog input logger to measure solar and wind power.

Negative Feedback in Electronics: A Look at the Opposite Side
Complementing his discussion last month on positive feedback, columnist George Novacek now takes a look at negative feedback. Just like positive feedback, negative feedback can significantly change or modify a circuit’s performance.

LF Quartz Resonator Tester: A Stimulating Discussion
Ed Nisley returns to the rich topic of low-frequency quartz resonators. This time he describes a tester built with an ordinary Arduino Nano and an assortment of inexpensive RF modules.

INTERESTING EMBEDDED PROJECTS

Simulating a Hammond Tonewheel Organ (Part 1) Mimicking a Mechanical Marvel
Hammond tonewheel organs were based upon additive sine-wave synthesis. Because of that, it’s possible to simulate the organ using a microcontroller program that feeds its output waveform to a DAC. Brian Millier takes on this project, making use of an ARM-based Teensy module to do the heavy lifting.

Machine Auto-Sorts Resistors: MCUs, Measurement and Motor Control
Typical electronics lab benches become littered with resistors from past projects. These three Cornell University graduates tackled this problem by building a resistor sorting system. It enables users to input multiple resistors, measure their resistance and sort them. The project integrates motor controllers, resistance measurement and a graphical user interface.

Microchip Adds AVR and SAM MCUs to Programming Service

Microchip Technology  has expanded its custom programming service to include AVR and SAM microcontrollers (MCUs). Users can add their custom code to MCUs from more than 30 AVR and SAM families, along with nearly all PIC MCUs and memory devices, directly from the manufacturer via microchipDIRECT.  Microchip  provides an online custom programming service to all of its clients.

Microchip’s custom programming service is available to any client regardless of their order size and can be used throughout the development process. From a7be46ac521844589d6de789549e7c153very small runs to verify that the code is working, all the way up through full-scale production runs, this cost-effective programming service offers customers the flexibility to add their code to any order size, from one device to millions. Additionally, each first verification order is complimentary and includes three free samples programmed to each client’s exact specifications.

To get started, clients choose their part number on microchipDIRECT and then add their code and other configuration settings, shown on the intuitive online form, directly into the encrypted website. The MCUs will then be programmed directly by Microchip with no need to involve a third party programming or manufacturing facility, thus eliminating the risk of code exposure during the programming process.

In addition to custom programming services, microchipDIRECT also offers value-added services such as tape and reeling, labels, ink dotting and more. With the largest inventory of Microchip products in the industry, microchipDIRECT provides a full service channel for all purchasing needs. The mobile-optimized website also offers global support in ten languages, volume pricing, live service agents, numerous payment options and order notifications for customer convenience. For more information visit www.microchipdirect.com.

Custom programming directly from Microchip is available for nearly all PIC MCUs and more than 30 AVR and SAM families with additional device support rolling out over the next year. For more information about this custom programming service, visit: www.microchipdirect.com/avr-sam-programming.html

Microchip Technology | www.microchip.com

October Circuit Cellar: A Sneak Preview

The October issue of Circuit Cellar magazine is on the launch pad, ready to deliver a selection of excellent embedded electronics articles covering trends, technology and design.

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TECHNOLOGY FOR DRONES / ROBOTIC HAND

Commercial Drone Design Solutions Take Flight: Chips, Boards and Platforms
The control, camera and comms electronics inside today’s drones have to pack in an ambitious amount of functionality. Circuit Cellar Chief Editor Jeff Child explores the latest Oct 327 Coverand greatest chip and module solutions serving today’s commercial and consumer drone designs.

Building a Robot Hand: With Servos and Electromyography
Learn how three Cornell University students developed a robotic hand. The system captures impulses generated by muscle contractions and then filters and feeds those signals to a microcontroller which controls finger movement.

 

CAN’T STOP THE SIGNAL

Signal Chain Tech Pushes Bandwidth Barriers: ADCs, FPGAs and DACs
FPGAs and D-A converters are key  technologies making up a signal chain. Here, Circuit Cellar Chief Editor Jeff Child steps through the state-of-the-art options available for crafting efficient, highly-integrated signal-centric systems.

Antenna Performance Measurement Made Easy: Covering the Basics
If you’re doing any kind of wireless communications design, chances are you’re including an antenna. Columnist Robert Lacoste shows how the task of measuring an antenna’s performance is less costly and exotic than you’d think.

MONITORING GEAR WITH MICROCONTROLLER BRAINS

Gas Monitoring and Sensing (Part 1): Fun with Fragrant Analysis
Columnist Jeff Bachiochi covers the background issues surrounding gas monitoring and sensing. Then he describes how he uses sensors, A/D conversion and Arduino technologies to do oxygen measurement.

Logger Device Tracks Amp Hours (Part 1): Measuring Home Electricity
Setting out to monitor and log electricity usage in his house, Bill Wachsmann built an amp-hour logger using a microcontroller and a clamp on ammeter.

KEEPING THE LEGACY ALIVE

Emulating Legacy Interfaces: Do it with Microcontrollers
There’s a number of important legacy interface technologies—like ISA and PCI—that are no longer supported by the mainstream computing industry. In his article Wolfgang Matthes examines ways to use microcontrollers  to emulate the bus signals of legacy interconnect schemes.

Building a Retro TV Remote : PIC MCU-Based Design
Dev Gualtieri embarks on building a retro-style TV remote, based on a Microchip PIC microcontroller. He outlines the phototransistor, battery and software designs he made along the way.

AND MORE FROM OUR EXPERT COLUMNISTS:

Get in the Loop on Positive Feedback: New Value in an Old Concept
Positive feedback loops are an important element of modern circuitry such as crystal oscillators, PLLs and other devices. Here, George Novacek goes deep into the math and circuit analysis of positive feedback and how it’s used in electronics.

Build an Embedded Systems Consulting Company (Part 6): Trade-Offs of Fixed-Price Contracts
Continuing his “Building an Embedded Systems Consulting Company” article series, this month Bob Japenga explores the nature of contracts and how fixed price contracts can be an effective, albeit dangerous tool in marketing.

Time-Oriented Task Manager

…for 8-bit PIC Microcontrollers

For many new embedded applications, an 8-bit MCU is just right. Pedro
shows how to build a time-oriented task manager using Microchip’s PIC
16F628A 8-bit microcontroller.

By Pedro Bertoleti

Microcontrollers are everywhere. From a simple remote control to an advanced car embedded system, microcontrollers surround us all. But while an 8-bit microcontroller is a relatively simple device, the software on them can get more sophisticated as more functionality is added to embedded systems. One of the most interesting advances in software technique is managing tasks. That involves enabling a microcontroller to execute several scheduled tasks, ensuring periodic and precise time execution. Here, we will examine how to implement a time-oriented task manager for a simple microcontroller—in this case, a Microchip 8-bit PIC microcontroller.

A graphic representation of a time-oriented task manager and its tasks

A graphic representation of a time-oriented task manager and its tasks

A good place to start is to ask: What is a task? A task is a part of a software program that’s dedicated to do something exclusively. In other words, a task is a piece of software that can be implemented and executed as an independent software program. Take, for example, an embedded system that has to blink an LED, send something through the UART interface and check an input’s state. Each one of these activities can be defined as a task. In a general way, each function of an embedded system can be defined as a task. A time-oriented task manager is a piece of software that performs these three main activities:

  • Execute tasks periodically
  • Execute tasks in the amount of time specified for them
  • Ensure time-precision measurement for the execution of tasks

In terms of coding, the time-oriented task manager and the tasks are different parts of the same software program. ….

Read the full article in the September 326 issue of Circuit Cellar

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September Circuit Cellar: A Sneak Preview

The September (326) issue of Circuit Cellar magazine serves up a meaty selection of useful technology resources along with inspiring, interesting embedded electronics design articles.

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Here’s a sneak preview of September Circuit Cellar:

FOCUS ON MICROCONTROLLERS

Getting Started with PSoC Microcontrollers (Part 3): Data Conversion, Capacitive Sensing and More
In Part 3, Nishant Mittal gets into some if the PSoC’s more complex features like Data Conversion.

Implementing a Time-Oriented Task Manager for 8-bit PIC Microcontrollers
Pedro Bertoleti shows readers how to build a time-oriented task manager using Microchip’s PIC 16F628A 8-bit microcontroller.

SPECIAL SECTION: EMBEDDED SECURITY

Microcontrollers Beef Up Security Features: Defense in a Connected World
Jeff Child explores the various flavors of embedded security features that microcontroller vendors are adding to their devices.

Resources for Embedded Security: Hardware, Software and Services
Circuit Cellar collects four pages worth of info about companies that provide embedded security products, tools and services.

TECHNOLOGY FEATURES

Using Power Audio Amplifiers in Untypical Ways (Part 1): Best Building Blocks
Petre Petrov shows readers how to use PAAs as universal building blocks to create analog signal generators, analog power supplies, voltage splitters and more.

Data Acquisition Advances Focus on Interfacing
Jeff Child discusses the latest data acquisition solutions, with a look at how interface technologies have evolved.

Future of IoT Communications: Will Upgraded Cellular Networks Benefit IoT?
This guest essay by Andrew Girson, CEO of Barr Group, explores how IoT will fare in the 5G network era.

MORE FROM OUR EXPERT COLUMNISTS:

Block Diagram Reduction and Automatic Tuning
George Novacek steps through how to think in terms of block diagrams to help you reduce system complexity early on in a design.

Numeric Precision vs. DDS Calculations
Using the full frequency resolution of a DDS chip outstrips the capabilities of floating point numbers. Ed Nisley looks at high-res frequency calibration and measurements in the DDS realm.

Deadbolt the Uninvited: Locked Out of My Home
In this Part 2 of Jeff Bachiochi’s electronic lock story, he gets into some of the power and remote-control issues of his electronic deadbolt lock project.

Diagnosing Performance Variations in HPC
Ayse K. Coskun delves into how application performance variations can cause inefficiency
in high-performance computing (HPC) systems and how to diagnose these variations.

Microchip Launched Two New MCU Families

Microchip Technology has made available its new SAM D5x and SAM E5x microcontroller (MCU) families. These new 32-bit MCU families offer extensive connectivity interfaces, high performance and robust hardware-based security for a wide variety of applications. The SAM D5/E5 MCUs combine the performance of an ARM Cortex-M4 processor with a Floating Point Unit (FPU). This combination offloads the Central Processing Unit (CPU), increasing system efficiency and enabling process-intensive applications on a low-power platform.

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Running at up to 120 MHz, the D5x and E5x MCUs feature up to 1 MB of dual-panel Flash with Error Correction Code (ECC), easily enabling live updates with no interruption to the running system. Additionally, these families are available with up to 256 KB of SRAM with ECC, vital to mission-critical applications such as medical devices or server systems.

These new MCUs have multiple interfaces that provide design flexibility for even the most demanding connectivity needs. Both families include a Quad Serial Peripheral Interface (QSPI) with an Execute in Place (XIP) feature. This allows the system to use high-performance serial Flash memories, which are both small and inexpensive compared to traditional pin parallel Flash, for external memory needs.

The SAM D5/E5 devices also feature a Secure Digital Host Controller (SDHC) for data logging, a Peripheral Touch Controller (PTC) for capacitive touch capabilities and best-in-class active power performance (65 microA/MHz) for applications requiring power efficiency. Additionally, the SAM E5 family includes two CAN-FD ports and a 10/100 Mbps Ethernet Media Access Controller (MAC) with IEEE 1588 support, making it well-suited for industrial automation, connected home and other Internet of Things (IoT) applications.

Both the SAM D5x and E5x families contain comprehensive cryptographic hardware and software support, enabling developers to incorporate security measures at a design’s inception. Hardware-based security features include a Public Key Cryptographic Controller (PUKCC) supporting Elliptic Curve Cryptography (ECC) and RSA schemes as well as an Advanced Encryption Standard (AES) cipher and Secure Hash Algorithms (SHA).

The SAM E54 Xplained Pro Evaluation Kit is available to kick-start development. The kit incorporates an on-board debugger, as well as additional peripherals, to further ease the design process. All SAM D5x/E5x MCUs are supported by the Atmel Studio 7 Integrated Development Environment (IDE) as well as Atmel START, a free online tool to configure peripherals and software that accelerates development. SAM D5x and SAM E5x devices are available today in a variety of pin counts and package options in volume production quantities. Devices in the SAM D5/E5 series are available starting at $2.43 each in 10,000 unit quantities. The SAM E54 Xplained Pro Evaluation Kit is available for $84.99 each.

Microchip | www.microchip.com

August Circuit Cellar: A Sneak Preview

The August (325) issue of Circuit Cellar magazine is jammed packed with useful technical information and inspiring, intriguing embedded electronics design stories.

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

 

Here’s a sneak preview of August Circuit Cellar:

FUN WITH GUITAR AMPLIFIERS!

Digital Guitar Amplifier/ Effects Processor—Part 2
Brian Millier details the digital guitar amplifier/effects unit he built using two Teensy Arduino modules.

A Range of Power Supplies for Hollow-State Guitar Amplifiers
Richard Honeycutt compares several different power supplies used for hollow-state guitar amplifiers.

MICROCONTROLLERS & PROCESSORS!

Firmware Upgrade with the PIC32
Nick Sicalides delves into performing firmware upgrades using a bootloader on the Microchip PIC32

Getting Started with PSoC Microcontrollers (Part 2): Putting PSoC to Work
Nishant Mittal goes even deeper on the Cypress PSoC providing some useful design examples.

Moore’s Law and the Chip Industry’s Perfect Storm
In this Interview Q&A Krste Asanovic explains RISC-V and the open sourcing of processor architecture.

SECURITY & RELIABILITY & ENCRYPTION!

Power Analysis of a Software DES Encryption Routine
Columnist Colin O’Flynn examines how to break a software implementation of the DES security routine.

Reliability and Failure Prediction: A New Take
Craig Armenti and Dave Wiens discuss a better way to simulate PCB vibration and acceleration.

Preventing Unwanted Entry
Columnist Jeff Bachiochi takes us inside his exploration of electronic lock systems, getting down to the fine details.

Future of Embedded Security: Wi-Fi to the Danger Zone
This guest essay by Adam Cecchetti, CEO of Deja vu Security, explains how memory leaks in your embedded system could have life or death consequences.

AND MORE FROM OUR EXPERT COLUMNISTS:

Automatic Control (Part 4) The Implementation
George Novacek describes the PID temperature controller he built for a meat smoker.

Fully Differential Amplifiers
Robert Lacoste sings the praises of fully differential amplifiers and presents a few designs using them.

Build an Embedded Systems Consulting Company (Part 5) Axiom Wrap-Up
Bob Japenga shares more insights on running a successful embedded design firm built to last.

Microchip Sequential Linear LED Driver Targets Offline Lighting

A next-generation sequential linear LED driver for offline lighting applications is now available from Microchip Technology. The CL88020, an extension of Microchip’s CL88XX family, is designed to drive a long string of low-cost LEDs directly from the 120 VAC line input. The product allows customers to create reliable, cost-effective and compact LED lighting applications by having High Power Factor (PF) without the need for switch-mode power conversion which is typically required for LED lighting design.

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The CL88020 was designed to minimize driver circuit component count to allow for a very small and efficient design. The simple design allows for a single-layered Printed Circuit Board (PCB) design. Unlike the conventional AC-DC switch mode power supply, the basic driver circuit consists of the CL88020 IC, two small ceramic capacitors and a bridge rectifier only. High-voltage capacitors, transformer or inductors, electromagnetic interference (EMI) filters or Power Factor Correction (PFC) circuitry are not required. This allows for a smaller solution size and a lower overall bill of material (BOM) cost as compared to traditional LED solutions.

Microchip | www.microchip.com