Designing High Performance GUIs

329 Brumby Lead Image for Web

UIs for the Multicore Era

For embedded developers, 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 examines these and other important UI design challenges.

By Phil Brumby
Mentor, Embedded Systems Division

The widespread proliferation of portable media devices has changed the way we interact with each other on a daily basis. In fact, there is now a generation of users who grew up with some type of touchscreen device. These users no longer see the UI as new or revolutionary, but rather as a standard piece of mobile device functionality. This phenomenon has created a new set of expectations. It means any device with an LCD must offer a fluid and intuitive user experience. It’s also expected that the touchscreen has to be “smartphone-like” whenever the device is powered on. Embedded system developers are now under pressure across multiple markets and device types to replicate the smartphone UI interactive experience.

The importance of getting the UI right is absolutely critical to the success of the device. Underpinning documented UI design methodologies is a need for the device to operate in a way that it will not impinge or be detrimental to the user experience. For developers, it’s necessary to understand the types of performance problems a typical end-user might encounter, and through an understanding of performance metrics employ various analyses to highlight the bottlenecks and performance degradation issues.

A key advantage to system start-up is analyzing selected input events.

A key advantage to system start-up is
analyzing selected input events.

TYPICAL PERFORMANCE ISSUES

To understand how to best analyze performance, it’s important to look at typical performance issues from the end-user’s perspective. In identifying these issues, developers can begin to identify the first data points or metrics needed for feedback on system performance.

Responsiveness: Responsiveness can be thought of as the time it takes for the user to receive feedback from the UI as a result of an input action made. Typically, this consists of a touchscreen input, but also includes hard key presses. Responsiveness is important as the user must feel the device performs within a certain timeframe to avoid the feeling a UI is “laggy” or slow to respond. Delays in updating the UI in response to input can result in frustration and mistakes made by the user.

Animation smoothness: Animation smoothness relates to the visible motion or change in appearance of elements displayed within the UI. As an element transitions from one point in 3D space to another, does it do so in a smooth manner that is pleasing to the eye? Animation smoothness is important because if the user perceives jagged or staggered motion in a transition, it will degrade the overall interactive experience.   …

Read the full article in the December 329 issue of Circuit Cellar

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Note: We’ve made the October 2017 issue of Circuit Cellar available as a free sample issue. In it, you’ll find a rich variety of the kinds of articles and information that exemplify a typical issue of the current magazine.

MCUs Feature Core Independent Peripherals

Microchip has expanded its PIC18 product line to include a new line of 8-bit microcontrollers that combine a Controller Area Network (CAN) bus with an extensive array of Core Independent Peripherals (CIPs). The CIPs increase system capabilities 37088982634_91c19d5d2b_owhile making it easier for designers to create CAN-based applications without the complexity of added software. A key advantage of using a K83 MCU in CAN-based systems is that the CIPs provide deterministic response to real time events, shorten design time and can be easily configured through the MPLAB Code Configurator (MCC) tool. The new family is well suited for applications using CAN in the medical, industrial and automotive markets, such as motorized surgical tables, asset tracking, ultrasound machines, automated conveyors and automotive accessories.

The PIC18 K83 devices contain 15 time-saving CIPs including: Cyclic Redundancy Check (CRC) with memory scan for ensuring the integrity of non-volatile memory; Direct Memory Access (DMA) enabling data transfers between memory and peripherals without CPU involvement; Windowed Watchdog Timer (WWDT) for triggering system resets; 12-bit Analog-to-Digital Converter with Computation (ADC2) for automating analog signal analysis for real-time system response; and Complementary Waveform Generator (CWG) enabling high-efficiency synchronous switching for motor control.

The new products are supported by MPLAB Code Configurator (MCC), a free software plug-in that provides a graphical interface to configure peripherals and functions specific to your application. MCC is incorporated into Microchip’s downloadable MPLAB X Integrated Development Environment (IDE) and the cloud-based MPLAB Xpress IDE. The family is also supported by the Curiosity High Pin Count (HPC) Development Board.

The PIC18F25K83 with 32 kB of Flash memory is available today for sampling and in volume production starting at $1.35 each in 10,000 unit quantities. The PIC18F26K83 with 64 KB of Flash memory is available today for sampling and in volume production starting at $1.44 each in 10,000 unit quantities. Each of these parts is available in 28-pin SPDIP, SOIC, SSOP, UQFN and QFN packages.

Mircochip Technology | www.microchip.com

IoT Tool Suite Supports Bluetooth 5

Rigado has announced its Edge Connectivity Suite with full support for Bluetooth 5. Designed for large-scale commercial IoT deployments, Rigado’s Edge Connectivity solution is comprised of Bluetooth 5 end-device modules and the Vesta IoT Gateway, which includes cloud-based tools for secure deployment and updating.

The Edge Connectivity Suite actively addresses a growing need for low-power wireless within commercial IoT applications like asset tracking, smart lighting and connected retail and hospitality. The company’s Bluetooth 5-enabled solutions support the flexibility, interoperability and security demands of large-scale commercial IoT deployments. Moreover, the suite addresses the market need for Edge Computing at scale, paving a secure and cost-effective road for data from device-to-cloud.

Specifically designed for companies who need to develop, deploy and manage a large number of connected devices and gateways, the Rigado Edge Connectivity Suite provides seamless integration between IoT devices and the Cloud. It includes:

  • BMD-340 angleCertified end device modules – Rigado modules (see photo) save connected product teams six months and $200K+ in design, test and certification. Fully Bluetooth 5 enabled, Rigado modules also feature mesh networking capabilities, ideal for applications like smart lighting, asset tracking, and connected retail.
  • Edge computing gateways – Rigado Vesta gateways manage connectivity to end devices and ensure data reaches public and private cloud services. They also support custom edge applications to process data and offer local device control. Flexible wireless options and customizability mean that companies can optimize their gateway for cost-effective enterprise deployment.
  • Cloud-based tools for secure deployment and updating– Companies require a scalable solution to securely manage updates to devices in the field. With that in mind, every Rigado gateway ships with Rigado’s provisioning and release management system that integrates with existing development tools for secure updating at scale.

Rigado | www.rigado.com

New Consortium to Focus on Industry 4.0

Advantech has announced that it has partnered with Mitsubishi Electric, Omron, NEC, IBM Japan and Oracle Japan to establish the “Edgecross Consortium” to overcome boundaries between companies and industries in order to realize collaboration between factory automation (FA) and IT. The objective is to create new value centered on edge computing. The joint press conference to announce the establishment of the Edgecross Consortium was held on November 6, 2017, in Tokyo, Japan, and the establishment of the consortium is planned for November 29, 2017.

content-image-1510189308969

The Edgecross Consortium will focus on the easy realization of FA and IT collaboration through its open software platform (“Edgecross Software Platform”), which is based on edge computing. By residing on the edge layer, the Edgecross Software Platform facilitates connectivity between factory shop floors and value chains, while enabling the rapid acquisition, analysis, and utilization of data, which are essential to smart manufacturing. In addition, user applications can be easily created and shared on the edge to realize various IoT utilization purposes.

The consortium aims to co-develop the platform specifications for and achieve certification of Edgecross products, in addition to co-marketing promotion and global co-selling for consortium members. Starting from Japan and then globally, you will be able to catch a glimpse of the Edgecross booth display at the SCF 2017 Fair and Smart Factory EXPO 2018. Advantech is organizing the IoT Co-Creation Summit from November 1 to 3, 2018, in Suzhou, China, with more than 2500 attendees from all over the world. The summit will seek to foster the three phases of growth brought about by IoT and to demonstrate the co-creation achievement of IoT WISE-PaaS, EISs, and SRPs.

Advantech | www.advantech.com

Tuesday’s 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.

LS-37K-3D8Already a Circuit Cellar Newsletter subscriber? Great!
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Our weekly Circuit Cellar Newsletter will switch its theme each week, so look for these in upcoming weeks:

Analog & Power. (12/5) 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. (12/12) 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. (12/19) 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.

A Year in the Drone Age

Input Voltage

–Jeff Child, Editor-in-Chief

JeffHeadShot

When you’re trying to keep tabs on any young, fast-growing technology, it’s tempting to say “this is the big year” for that technology. Problem is that odds are the following year could be just as significant. Such is the case with commercial drones. Drone technology fascinates me partly because it represents one of the clearest examples of an application that wouldn’t exist without today’s level of chip integration driven by Moore’s law. That integration has enabled 4k HD video capture, image stabilization, new levels of autonomy and even highly compact supercomputing to fly aboard today’s commercial and consumer drones.

Beyond the technology side, drones make for a rich topic of discussion because of the many safety, privacy and regulatory issues surrounding them. And then there are the wide-open questions on what new applications will drones be used for?

For its part, the Federal Aviation Administration has had its hands full this year regarding drones. In the spring, for example, the FAA completed its fifth and final field evaluation of potential drone detection systems at Dallas/Fort Worth International Airport. The evaluation was the latest in a series of detection system evaluations that began in February 2016 at several airports. For the DFW test, the FAA teamed with Gryphon Sensors as its industry partner. The company’s drone detection technologies include radar, radio frequency and electro-optical systems. The FAA intends to use the information gathered during these kinds of evaluations to craft performance standards for any drone detection technology that may be deployed in or around U.S. airports.

In early summer, the FAA set up a new Aviation Rulemaking Committee tasked to help the agency create standards for remotely identifying and tracking unmanned aircraft during operations. The rulemaking committee will examine what technology is available or needs to be created to identify and track unmanned aircraft in flight.

This year as also saw vivid examples of the transformative role drones are playing. A perfect example was the role drones played in August during the flooding in Texas after Hurricane Harvey. In his keynote speech at this year’s InterDrone show, FAA Administrator Michael Huerta described how drones made an incredible impact. “After the floodwaters had inundated homes, businesses, roadways and industries, a wide variety of agencies sought FAA authorization to fly drones in airspace covered by Temporary Flight Restrictions,” said Huerta. “We recognized that we needed to move fast—faster than we have ever moved before. In most cases, we were able to approve individual operations within minutes of receiving a request.”

Huerta went on to described some of the ways drones were used. A railroad company used drones to survey damage to a rail line that cuts through Houston. Oil and energy companies flew drones to spot damage to their flooded infrastructure. Drones helped a fire department and county emergency management officials check for damage to roads, bridges, underpasses and water treatment plants that could require immediate repair. Meanwhile, cell tower companies flew them to assess damage to their towers and associated ground equipment and insurance companies began assessing damage to neighborhoods. In many of those situations, drones were able to conduct low-level operations more efficiently—and more safely—than could have been done with manned aircraft.

“I don’t think it’s an exaggeration to say that the hurricane response will be looked back upon as a landmark in the evolution of drone usage in this country,” said Huerta. “And I believe the drone industry itself deserves a lot of credit for enabling this to happen. That’s because the pace of innovation in the drone industry is like nothing we have seen before. If people can dream up a new use for drones, they’re transforming it into reality.”

Clearly, it’s been significant year for drone technology. And I’m excited for Circuit Cellar to go deeper with our drone embedded technology coverage in 2018. But I don’t think I’ll dare say that “this was the big year” for drones. I have a feeling it’s just one of many to come.

This appears in the December (329) issue of Circuit Cellar magazine

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Ultra Wide Input Range Power Converters

Aimtec has announced the release of two new series of regulated AC to DC power converters, the AME10-BJZ and AME20-BJZ. These new series will expedite and simplify industrial and commercial product design in a low cost solution. The new regulated 10 W and 20 W AME10-BJZ and AME20-BJZ series are packaged in industry standard packages: 62.0 x 45.0 x 30.0 mm (2.44 x 1.77 x 1.18 inches) and 70.00 x 48.00 x 30.0 mm (2.76 x 1.89 x 1.18 inches) respectively. They meet the IEC/EN 62368-1 standards and are EN55032 class B compliant.

200_sq_ame10-bjz-press-jpg-94f2The internal EMC filtering reduces the need for external filtering components reducing production costs and are well suited for a wide range of applications including electric metering of three phase AC supply, industrial applications as well as commercial equipment applications. The standard package is available with 3.3, 5, 9, 12, 15 and 24 VDC outputs. These series offer over current, over voltage and short circuit protection while accepting an ultra-wide input range of 90-528 VAC or 100-745 VDC at 47-63 Hz input frequency. This series offers a high MTBF of 300,000 hours with an efficiency of up to 83%. The new AME10-BJZ and AME20-BJZ series feature high input/output isolation of 4,000 VAC and operate from a bone chilling -40°C to a blistering +70°C with full power output from -10°C to +55°C.

Aimtec | www.aimtec.com

MCU Enables 3D Graphics in Car Displays

Cypress Semiconductor has announced a new series in its Traveo automotive microcontroller family with more memory to support a hybrid instrument cluster with 3D graphics and up to 6 traditional gauges, as well as a head-up display. The highly integrated, single-chip devices in the S6J32xEK series include an advanced 3D and 2.5D graphics engine and provide scalability with Cypress’ low-pin-count HyperBus memory interface. The series continues Cypress’ expansion of its broad automotive portfolio with differentiated system performance via its MCUs, wireless radios, capacitive-touch solutions, memories and Power Management ICs (PMICs).
Cypress Traveo Automotive MCUs 2017

The Traveo S6J32xEK series integrates up to 4MB of high-density embedded flash, 512 KB RAM and 2 MB of Video RAM, an ARM Cortex-R5 core at 240 MHz performance, a Low-Voltage Differential Signaling (LVDS) video output, a Low-Voltage Transistor-Transistor Logic (LVTTL) video output and a 6x stepper motor control. This combination enables the devices to serve as single-chip solutions to drive two displays. The devices have up to two 12-pin HyperBus memory interfaces that dramatically improve read and write performance of graphical data and other data or code.

A single HyperBus interface can be used to connect to two memories for Firmware Over-The-Air (FOTA) updates, which enable end-users to get software fixes and new features and applications for their vehicles on-the-go. The devices support all in-vehicle networking standards required for instrument clusters, including Controller Area Network-Flexible Data (CAN-FD) and Ethernet AVB. Additionally, the series provides robust security with integrated enhanced secure hardware extension (eSHE) support.

The Traveo S6J32xEK series include 50 channels of 12-bit Analog to Digital Converters (ADC), 12 channels of multi-function serial interfaces and I2S interfaces with an audio to output the complex, high-quality sounds required in today’s instrument clusters. The devices’ support for Ethernet AVB delivers increased bandwidth in multimedia applications and reduced programming time. The S6J32xEK series offers functional safety features to support Automotive Safety Integrity Level (ASIL) B, and the devices feature a wide ambient temperature range of -40˚C to +105˚C. The Traveo family is backed by a comprehensive tools and software ecosystem that simplifies system integration, including AUTOSAR MCAL 4.0.3 support.

The Traveo S6J32xEK series is sampling now and will be in production in the first quarter of 2018. The MCUs are available in a 208-pin and 216-pin thermally enhanced quad flat package (TEQFP).

Cypress Semiconductor | www.cypress.com

Intel & Micron Expand Manufacturing Effort

Intel and Micron have announced the completion of an expansion to Building 60 (B60) at the IM Flash facilities in Lehi, Utah. The expanded fab will produce 3D XPoint memory media, a building block of Intel Optane technology that includes Intel Optane memory for clients, the recently announced Intel Optane SSD 900P Series and new capacities and form factors of the Intel Optane SSD DC P4800X Series. A ribbon-cutting was held at the facility with Utah Gov. Gary Herbert, employees of the facility and representatives from Intel and Micron.

Intel-Optane-SSD-900P-Series

The Intel Optane SSD 900P Series half-height half-length add-in card is available in 480 GB and 280 GB capacities.

The IM Flash joint venture was created in 2006 to manufacture non-volatile memory for both Intel and Micron, starting with NAND for use in SSDs, phones, tablets and more. In 2015, IM Flash began manufacturing 3D XPoint technology, the first entirely new memory media in 25 years. The technology was developed to meet the quickly expanding data needs for all types of customers. 3D XPoint technology uses a crosspoint structure to deliver a cell and array architecture that can switch states significantly faster than NAND.

Intel recently announced the Intel Optane SSD 900P Series for use in desktop and workstation PCs. It delivers incredibly low latency and best-in-class random read and write performance at low queue depths. Additionally, Intel expanded the Intel Optane technology offerings for the data center, introducing 750GB capacity and 2.5-inch U.2 form factor versions of the Intel Optane SSD DC P4800X Series. For details on these products and all Intel SSDs, visit Intel’s solid state drives website.

Intel | www.intel.com

Micron Technology | www.micron.com

Next Newsletter: IoT Technology 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.

Wind-River-Helix-Device-Cloud-Image-1_small1Already 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.(11/28) 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. (12/5) 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 (12/12) 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.

1 W DC-DC Converters Medical Approved

MINMAX Technology has announced the MINMAX MAU01M / MSCU01M series, a new range of high performance 1 W medical safety approved DC-DC converters with encapsulated SIP-7 & SMD packages. They are specifically designed for medical applications. The series includes  models available for input voltages of 4.5 VDC to 5.5 VDC, 10.8 VDC to 13.2 VDC, and 21.6 to 26.4 VDC. The I/O isolation is specified for 4,000 VAC with reinforced insulation and ated for a 300 Vrms working voltage.

40e5a6c0900620d4a836fb17d0ef3ecbFurther features include short circuit protection, a low leakage current of 2 μA max. and operating ambient temperating range of -40°C to 95°C. This is achieved without de-rating and with a high efficiency of up to 84%. The MAU01M / MSCU01M series conforms to the 4th edition medical EMC standard. It meets 2xMOPP (Means of Patient Protection) per 3rd edition of IEC/EN 60601-1 & ANSI/AAMI ES60601-1. The MAU01M / MSCU01M series offer an economical solution for demanding medical instrument applications that require a certified supplementary and reinforced insulation system to comply with latest medical safety approvals under the 2x MOPP requirements.

MINMAX Technology | www.minmaxpower.com

Wide Range Power Monitor Embeds ADCs

Analog Devices, acquired earlier this year by Linear Technology, has announced the LTC2992, a wide range I²C system monitor that monitors the current, voltage and power of two 0 V to 100 V rails without additional circuitry. The LTC2992 has flexible power supply options, deriving power from a 3 V to 100 V  monitored supply, a 2.7 V to 100 V secondary supply, or from the on-board shunt regulator. These supply options eliminate the need for a separate buck regulator, shunt regulator or inefficient resistive divider while monitoring any 0 V to 100 V rail. The LTC2992 is a simple, single-IC solution that uses three delta-sigma ADCs and a multiplier to provide 8- or 12-bit current and voltage measurements and 24-bit power readings.

LTC2992The LTC2992’s wide operating range is ideal for many applications, especially 48V telecom equipment, advanced mezzanine cards (AMC) and blade servers. The onboard shunt regulator provides support for supplies greater than 100V and negative supply monitoring. The LTC2992 measures current and voltage either continuously or on-demand, calculates power and stores all of this information along with minimum and maximum values in I²C accessible registers. Four GPIOs can also be configured as ADC inputs to measure neighboring auxiliary voltages. Measurements are made with only ±0.3% of total unadjusted error (TUE) over the entire temperature range. If any parameter trips the user-programmable thresholds, the LTC2992 flags an alert register and pin per the SMBus alert response protocol. The 400 kHz I²C interface features nine device addresses, a stuck bus reset timer, and a split SDA pin that simplifies I²C opto-isolation.  The LTC2992-1 version offers an inverted data output I²C pin for use with inverting opto-isolator configurations.

The LTC2992 and LTC2992-1 are offered in commercial, industrial and automotive versions, supporting operating temperature ranges from 0°C to 70°C, –40°C to 85°C and –40°C to 125°C, respectively. Both versions are available today in RoHS-compliant, 16-lead 4mm x 3mm DFN and 16-lead MSOP packages. Pricing starts at $3.85 each in 1,000-piece quantities. Please visit www.linear.com/products/power_monitors for more product selection and information.

Summary of Features:

  • Rail-to-Rail Input Range: 0 V to 100 V
  • Wide Input Supply Range: 2.7 V to 100 V
  • Shunt Regulator for Supplies >100 V
  • Three Delta-Sigma ADCs with Less Than ±0.3% TUE
  • 12-Bit Resolution for Currents & Voltages
  • Four GPIOs Configurable as ADC Inputs
  • Shutdown Mode with IQ < 50 µA
  • I²C Interface
  • Split SDA Pin Eases Opto-Isolation
  • Available in 16-Lead 4mm x 3mm DFN & 16-Lead MSOP Packages

Analog Devices | www.analog.com

Linear Technology | www.linear.com

December Circuit Cellar: A Sneak Preview

The December issue of Circuit Cellar magazine is coming soon. Want a sneak peak? We’ve got a great selection of excellent embedded electronics articles for you.

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

 Here’s a sneak preview of December Circuit Cellar:

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.

Issue 328 November: EQ Questions

Review these four Test Your EQ problems that appeared in Circuit Cellar November (328). Test your knowledge. Answers appear in the December issue (329)

Question 1USB is by far the most common way to connect peripherals to PCs these days, yet there seems to be a lot of misinformation about USB floating around the Internet. Let’s try to address some basic facts about USB. It is fairly well understood that the simplest form of USB uses four wires, two for power and two for data. Describe how the data wires are used.

Question 2The “B” in USB stands for “bus”. In what sense is USB a bus?

Question 3There are standard colors specified for the wires in a USB cable. What are they?

 Question 4The new USB “C” connector has an important feature that no previous USB connector has. What is it?

Issue 326 September: EQ Questions

Review these four Test Your EQ problems that appeared in Circuit Cellar September (326). Test your knowledge. Answers appear in the October issue (327)

.

Question 1

Asynchronous (dual-clock) FIFOs are important functions in high-speed digital design, especially when data needs to be transferred between two clock domains. Let’s talk about the implementation of such a FIFO, and the nuances of some of the details.

eq0691_fig1

One of the central elements in the design is the “true dual port” RAM block. Describe the essential features of this block.

Question 2

In order to implement a FIFO, a write address counter and a read address counter are required. Each counter wraps back to zero when it reaches its maximum count.

In order to determine the number of words currently in the FIFO, the values of the two counters must be subtracted. However, the two counters are in two different clock domains, which means that the value of each one needs to be transferred to the other clock domain. Why is Gray code used for this purpose?

Question 3

Given that it takes a significant number of clocks to transfer a counter value from one clock domain to the other, what does this imply about the overall data latency through the FIFO?

Question 4

What about the input side of the FIFO? Does the synchronization delay create any danger that it will overwrite old data before it can be read?