Read Your Technical Documentation (EE Tip #145)

Last year we had a problem that showed up only after we started making the product in 1,000-piece runs. The problem was that some builds of the system took a very long time to power up. We had built about 10 prototypes, tested the design over thousands of power ups, and it tested just fine (thanks to POC-IT). Then the 1,000-piece run uncovered about a half-dozen units that had variable power-up times—ranging from a few seconds to more than an hour! Replacing the watchdog chip that controlled the RESET line to an ARM9 processor fixed the problem.

But why did these half dozen fail?

Many hours into the analysis we discovered that the RESET line out of the watchdog chip on the failed units would pulse but stay low for long periods of time. A shot of cold air instantly caused the chip to release the RESET. Was it a faulty chip lot? Nope. Upon a closer read of the documentation, we found that you cannot have a pull-up resister on the RESET line. For years we always had pull-ups on RESET lines. We’d missed that in the documentation.

Like it or not, we have to pour over the documentation of the chips and software library calls we use. We have to digest the content carefully. We cannot rely on what is intuitive.

Finally, and this is much more necessary than in years past, we have to pour over the errata sheets. And we need to do it before we commit the design. A number of years ago, a customer designed a major new product line around an Atmel ARM9. This ARM9 had the capability of directly addressing NOR memory up to 128 MB. Except for the fact that the errata said that due to a bug it could only address 16 MB. Ouch! Later we had problems with the I2C bus in the same chip. At times, the bus would lock up and nothing except a power cycle would unlock it. Enter the errata. Under some unmentioned conditions the I2C state machine can lock up. Ouch! In this case, we were able to use a bit-bang algorithm rather than the built-in I2C—but obviously at the cost of money, scheduling, and real time.—Bob Japenga, CC25, 2013

Embedded SOM with Linux-Based RTOS

National Instruments has introduced an embedded system-on-module (SOM) development board with integrated Linux-based real-time operating system (RTOS).NIsom

Processing power in the 2” x 3” SOM comes from a Xilinx Zync-7020 all programmable SOC running a dual core ARM Cortex-A9 at 667 MHz. A built-in, low-power Artix-7 FPGA offers 160 single-ended I/Os and Its dedicated processor I/O include Gigabit Ethernet USB 2.0 host, USB 2.0 host/device, SDHC, RS-232, and Tx/Rx. The SOM’s power requirements are typically 3 to 5 W.

The SOM integrates a validated board support package (BSP) and device drivers together with the National Instruments Linux real-time OS. The SOM board is supplied with a full suite of middleware for developing an embedded OS, custom software drivers, and other common software components.

The LabVIEW FPGA graphical development platform eliminates the need for expertise in the design approach using a hardware description language.

[Via Elektor]

 

New DSP “Lab-in-a-Box” for ARM-Based Audio Systems

Cambridge, UK-based, ARM and its partners will start shipping a DSP “Lab-in-a-Box” (LiB) to universities worldwide to help boost practical skills development and the creation of new ARM-based audio systems. This will include products such as high-definition home media and voice-controlled home automation systems. The LiB kits contain ARM Cortex-M4-based microcontroller boards by STMicroelectronics and audio cards from Wolfson Microelectronics and Farnell element14.ARMDSPLiBWeb

As the centerpiece of the ARM University Program, LiB packages offer ARM-based technology and high-quality teaching and training materials that support electronics and computer engineering courses. DSP courses have traditionally used software simulation packages, or hands-on labs using relatively expensive development kits costing around $300 per student. By comparison, this new DSP LiB will cost around $50 and will allow students to practice theory with advanced hardware sourced from widely-available products.

“Our Lab-in-a-Box offerings are proving hugely popular in universities because of the low-cost access to state-of-the-art technology,” said Khaled Benkrid, manager of the Worldwide University Program, ARM. “The DSP kits, powered by ARM Cortex-M4-based processors, enable high performance yet energy-efficient digital signal processing at a very affordable price. We expect to see them being used by students to create commercially-viable audio applications and it’s another great example of our partnership supporting engineers in training and beyond.”

The DSP LiB will begin shipping to universities in July 2014. It is the latest in a series of initiatives led by ARM which span multiple academic topics including embedded systems design, programming and SoC design. The DSP kits will also be offered to developers outside academia at a later date.

[via audioXpress.com]

Client Profile: ARM, Ltd.

ARM, Ltd.

ARM, Ltd.
110 Fulbourn Road
Cambridge, GB-CB1 9NJ,
Great Britain

www.arm.com
www.arm.com/tools

Contact: sales.us@keil.com

Embedded Products/Services: The ARM tools range offers two software development families that provide you with all the necessary tools for every stage of your software development workflow.

ARM Development Studio 5 (DS-5) provides best-in-class tools for a broad range of ARM processor-based platforms, including application processors and multicore SoCs. Find out more by visiting www.arm.com/products/tools/software-tools/ds-5/index.php.

Keil MDK-ARM is a complete software development toolkit for ARM processor-based microcontrollers. It is the right choice for embedded applications based on the ARM Cortex-M series, ARM7, ARM9, and Cortex-R4 processors. To find out more, visit www.arm.com/products/tools/software-tools/mdk-arm/index.php.

Product Information: The MDK-ARM is a complete software development environment for Cortex-M, Cortex-R4, ARM7, and ARM9 processor-based devices. MDK-ARM is specifically designed for microcontroller applications. It is easy to learn and use, yet powerful enough for the most demanding embedded applications.

The MDK-ARM is available in four editions: MDK-Lite, MDK-Basic, MDK-Standard, and MDK-Professional. All editions provide a complete C/C++ development environment and MDK-Professional includes extensive middleware libraries.

The Future of Data Acquisition Technology

Maurizio Di Paolo Emilio

Maurizio Di Paolo Emilio

By Maurizio Di Paolo Emilio

Data acquisition is a necessity, which is why data acquisition systems and software applications are essential tools in a variety of fields. For instance, research scientists rely on data acquisition tools for testing and measuring their laboratory-based projects. Therefore, as a data acquisition system designer, you must have an in-depth understanding of each part of the systems and programs you create.

I mainly design data acquisition software for physics-related experiments and industrial applications. Today’s complicated physics experiments require highly complex data acquisition systems and software that are capable of managing large amounts of information. Many of the systems require high-speed connections and digital recording. And they must be reconfigurable. Signals that are hard to characterize and analyze with a real-time display are evaluated in terms of high frequencies, large dynamic range, and gradual changes.

Data acquisition software is typically available in a text-based user interface (TUI) that comprises an ASCII configuration file and a graphic user interface (GUI), which are generally available with any web browser. Both interfaces enable data acquisition system management and customization, and you don’t need to recompile the sources. This means even inexperienced programmers can have full acquisition control.

Well-designed data acquisition and control software should be able to quickly recover from instrumentation failures and power outages without losing any data. Data acquisition software must provide a high-level language for algorithm design. Moreover, it requires data-archiving capability for verifying data integrity.

You have many data acquisition software options. An example is programmable software that uses a language such as C. Other software and data acquisition software packages enable you to design the custom instrumentation suited for specific applications (e.g., National Instruments’s LabVIEW and MathWorks’s MATLAB).

In addition to data acquisition software design, I’ve also been developing embedded data acquisition systems with open-source software to manage user-developed applications. The idea is to have credit-card-sized embedded data acquisition systems managing industrial systems using open-source software written in C. I’m using an ARM processor that will give me the ability to add small boards for specific applications (e.g., a board to manage data transmission via Wi-Fi or GSM).

A data acquisition system’s complexity tends to increase with the number of physical properties it must measure. Resolution and accuracy requirements also affect a system’s complexity. To eliminate cabling and provide for more modularity, you can combine data acquisition capabilities and signal conditioning in one device.

Recent developments in the field of fiber-optic communications have shown longer data acquisition transmission distances can cause errors. Electrical isolation is also an important topic. The goal is to eliminate ground loops (common problems with single-ended measurements) in terms of accuracy and protection from voltage spikes.

During the last year, some new technological developments have proven beneficial to the overall efficacy of data acquisition applications. For instance, advances in USB technology have made data acquisition and storage simpler and more efficient than ever (think “plug and play”). Advances in wireless technology have also made data transmission faster and more secure. This means improved data acquisition system and software technologies will also figure prominently in smartphone design and usage.

If you look to the future, consumer demand for mobile computing systems will only increase, and this will require tablet computers to feature improved data acquisition and storage capabilities. Having the ability to transmit, receive, and store larger amounts of data with tablets will become increasingly important to consumers as time goes on. There are three main things to consider when creating a data acquisition-related application for a tablet. Hardware connectivity: Tablets have few control options (e.g., Wi-Fi and Bluetooth). Program language support: Many tablets support Android apps created in Java. Device driver availability: Device drivers permit a high-level mode to easily and reliably execute a data acquisition board’s functionality. C and LabVIEW are not supported by Android or Apple’s iOS. USB, a common DAQ bus, is available in a set of tablets. In the other case, an adapter is required. In these instances, moving a possible data acquisition system to a tablet requires extra attention.

For all of the aforementioned reasons, I think field-programmable arrays (FPGAs) will figure prominently in the evolution of data acquisition system technology. The flexibility of FPGAs makes them ideal for custom data acquisition systems and embedded applications.

CC25 Is Now Available

Ready to take a look at the past, present, and future of embedded technology, microcomputer programming, and electrical engineering? CC25 is now available.

Check out the issue preview.

We achieved three main goals by putting together this issue. One, we properly documented the history of Circuit Cellar from its launch in 1988 as a bi-monthly magazine
about microcomputer applications to the present day. Two, we gathered immediately applicable tips and tricks from professional engineers about designing, programming, and completing electronics projects. Three, we recorded the thoughts of innovative engineers, academics, and industry leaders on the future of embedded technologies ranging from
rapid prototyping platforms to 8-bit chips to FPGAs.

The issue’s content is gathered in three main sections. Each section comprises essays, project information, and interviews. In the Past section, we feature essays on the early days of Circuit Cellar, the thoughts of long-time readers about their first MCU-based projects, and more. For instance, Circuit Cellar‘s founder Steve Ciarcia writes about his early projects and the magazine’s launch in 1988. Long-time editor/contributor Dave Tweed documents some of his favorite projects from the past 25 years.

The Present section features advice from working hardware and software engineers. Examples include a review of embedded security risks and design tips for ensuring system reliability. We also include short interviews with professionals about their preferred microcontrollers, current projects, and engineering-related interests.

The Future section features essays by innovators such as Adafruit Industries founder Limor Fried, ARM engineer Simon Ford, and University of Utah professor John Regehr on topics such as the future of DIY engineering, rapid prototyping, and small-RAM devices. The section also features two different sets of interviews. In one, corporate leaders such as Microchip Technology CEO Steve Sanghi and IAR Systems CEO Stefan Skarin speculate on the future of embedded technology. In the other, engineers such as Stephen Edwards (Columbia University) offer their thoughts about the technologies that will shape our future.

As you read the issue, ask yourself the same questions we asked our contributors: What’s your take on the history of embedded technology? What can you design and program today? What do you think about the future of embedded technology? Let us know.

CC 25th Anniversary Issue: The Past, Present, and Future of Embedded Design

In celebration of Circuit Cellar’s 25th year of publishing electrical engineering articles, we’ll release a special edition magazine around the start of 2013. The issue’s theme will be the past, present, and future of embedded electronics. World-renowned engineers, innovators, academics, and corporate leaders will provide essays, interviews, and projects on embedded design-related topics such as mixed-signal designs, the future of 8-bit chips, rapid prototyping, FPGAs, graphical user interfaces, embedded security, and much more.

Here are some of the essay topics that will appear in the issue:

  • The history of Circuit Cellar — Steve Ciarcia (Founder, Circuit Cellar, Engineer)
  • Do small-RAM devices have a future? — by John Regehr (Professor, University of Utah)
  • A review of embedded security risks — by Patrick Schaumont (Professor, Virginia Tech)
  • The DIY electronics revolution — by Limor Fried (Founder, Adafruit Industries)
  • The future of rapid prototyping — by Simon Ford (ARM mbed, Engineer)
  • Robust design — by George Novacek (Engineer, Retired Aerospace Executive)
  • Twenty-five essential embedded system design principles — by Bob Japenga (Embedded Systems Engineer, Co-Founder, Microtools Inc.)
  • Mixed-signal designs: the 25 errors you’ll make at least once — by Robert Lacoste (Founder, Alciom; Engineer)
  • User interface tips for embedded designers — by Curt Twillinger (Engineer)
  • Thinking in terms of hardware platforms, not chips — by Clemens Valens (Engineer, Elektor)
  • The future of FPGAs — by Colin O’Flynn (Engineer)
  • The future of e-learning for engineers and programmers — by Marty Hauff (e-Learning Specialist, Altium)
  • And more!

Interviews

We’ll feature interviews with embedded industry leaders and forward-thinking embedded design engineers and programmers such as:

More Content

In addition to the essays and interviews listed above, the issue will also include:

  • PROJECTS will be available via QR codes
  • INFOGRAPHICS depicting tech-related likes, dislikes, and ideas of hundreds of engineers.
  • And a few surprises!

Who Gets It?

All Circuit Cellar subscribers will receive the 25th Anniversary issue. Additionally, the magazine will be available online and promoted by Circuit Cellar’s parent company, Elektor International Media.

Get Involved

Want to get involved? Sponsorship and advertising opportunities are still available. Find out more by contacting Peter Wostrel at Strategic Media Marketing at 978-281-7708 (ext. 100) or peter@smmarketing.us. Inquire about editorial opportunities by contacting the editorial department.

About Circuit Cellar

Steve Ciarcia launched Circuit Cellar magazine in 1988. From its beginning as “Ciarcia’s Circuit Cellar,” a popular, long-running column in BYTE magazine, Ciarcia leveraged his engineering knowledge and passion for writing about it by launching his own publication. Since then, tens of thousands of readers around the world have come to regard Circuit Cellar as the #1 source for need-to-know information about embedded electronics, design, and programming.

DIY 10.1˝ Touchscreen Home Control System

Domotics (home automation) control systems are among the most innovative and rewarding design projects creative electrical engineers can undertake. Let’s take a look at an innovative Beagle Board-based control system that enables a user to control lights with a 10.1˝ capacitive touchscreen.

Domotics control system

The design features the following modules:

• An I/O board for testing purposes
• An LED strip board for controlling an RGB LED strip
• A relay board for switching 230-VAC devices
• An energy meter for measuring on/off (and also for logging)

ELektor editor and engineer Clemens Valens recently interviewed Koen van Dongen about the design. Van Dongen describes the system’s electronics and then demonstrates how to use the touchscreen to control a light and LED strip.

As Valens explains suggests, it would be a worthwhile endeavor to incorporate a Wi-Fi connection to enable cellphone and tablet control. If you build such system, be sure to share it with our staff. Good luck!

CircuitCellar.com is an Elektor International Media website.

Raspberry Pi Now Shipping

Got Raspberry Pi? Probably not. But rest assured. The wait is almost over.

After receiving an inquiry about the status of Raspberry Pi from a Circuit Cellar member earlier today, I decided to do a bit of research. It didn’t take long to figure out that hundreds of thousands of orders have been placed and shipping has begun.

Raspberry Pi (Source: Raspberry Pi Foundation & posted on Elektor.com)

TheInquirer.net reported last week that more than 350,000 orders have been placed since February and the next shipments are scheduled for May.

According to an April 18 post by element14’s Sagar Jethani, shipping is underway and “will be made strictly in the order that commitments were received within each region — Europe, Asia, and the Americas.” He added that “Everyone who ordered before 18th April will definitely receive their Raspberry Pi before the end of June. Those placing new orders from today can expect a July delivery.”

I encourage Circuit Cellar members to tell us what they think about Raspberry Pi once their receive their orders. We’ll be happy to review project articles for publication in print or online.

The Raspberry Pi Foundation’s compact (85.60 mm × 53.98 mm × 17 mm) single-bard computer features a Broadcom BCM2835, an ARM1176JZFS, and a Videocore 4 GPU. The ARM GNU/Linux system costs $25.

You can order the Raspberry Pi from element14 and RS Components.

Check out my first Raspberry Pi post for additional information.

Tech Highlights from Design West: RL78, AndroPod, Stellaris, mbed, & more

The Embedded Systems Conference has always been a top venue for studying, discussing, and handling the embedded industry’s newest leading-edge technologies. This year in San Jose, CA, I walked the floor looking for the tech Circuit Cellar and Elektor members would love to get their hands on and implement in novel projects. Here I review some of the hundreds of interesting products and systems at Design West 2012.

RENESAS

Renesas launched the RL78 Design Challenge at Design West. The following novel RL78 applications were particularly intriguing.

  • An RL78 L12 MCU powered by a lemon:

    A lemon powers the RL78 (Photo: Circuit Cellar)

  • An RL78 kit used for motor control:

    The RL78 used for motor control (Photo: Circuit Cellar)

  • An RL78 demo for home control applications:

    The RL78 used for home control (Photo: Circuit Cellar)

TEXAS INSTRUMENTS

Circuit Cellar members have used TI products in countless applications. Below are two interesting TI Cortex-based designs

A Cortex-M3 digital guitar (you can see the Android connection):

TI's digital guitar (Photo: Circuit Cellar)

Stellaris fans will be happy to see the Stellaris ARM Cortex -M4F in a small wireless application:

The Stellaris goes wireless (Photo: Circuit Cellar)

NXP mbed

Due to the success of the recent NXP mbed Design Challenge, I stopped at the mbed station to see what exciting technologies our NXP friends were exhibiting. They didn’t disappoint. Check out the mbed-based slingshot developed for playing Angry Birds!

mbed-Based sligshot for going after "Angry Birds" (Photo: Circuit Cellar)

Below is a video of the project on the mbedmicro YouTube page:

FTDI

I was pleased to see the Elektor AndroPod hard at work at the FTDI booth. The design enables users to easily control a robotic arm with Android smartphones and tablets.

FTDI demonstrates robot control with Android (Photo: Circuit Cellar)

As you can imagine, the possible applications are endless.

The AndroPod at work! (Photo: Circuit Cellar)

Radiant Floor Heating Zone Controller Project

Even if you aren’t interested in designing a radiant floor zoned heating system, you can study this innovative project and apply what you learn to any number of building control and automation applications. Dalibor Zaric’s Radiant Floor Heating Zone Controller is built around an NXP Semiconductors LPC2134 ARM processor that’s connected to an Echelon Pyxos chip. The project won Second Place in Echelon’s 2007 “Control Without Limits” design competition.

The heat zone controller system (Source: Echelon & Dalibor Zaric)

Zaric provides the following details in his project documentation:

“• Power supply to unit is 24VAC and controller has switching power supply to provide 24VDC for Pyxos network as well 5V for logic, there is 3.3V linear regulator as well.

• There are four relay with 24VAC output to power up thermoelectric zone valve on radiant floor heating manifold. These outputs are protected with 1.85A self resetting fuse to prevent overloading. This block has as well 24VAC/DC dry contact to provide a call for heat to boiler or optional zones pump.

• Pyxos power supply filter and Pyxos chip provides Pyxos network connection for future sensors and thermostats. Pyxos thermostat will be more cost effective than regular LONWorks sensors/thermostats.

• RS-485 driver will provide future Modbus connection for local touch screens or smart home systems with Modbus connections. There is end of line resistors enabled with the dip switches beside connector.

• 3150 Neuron board with 64K flash provides LONWorks connection to the controller.”

 

The heat zone controller diagram (Source: Echelon & Dalibor Zaric)

For more information about Pyxos technology, visit www.echelon.com.

This winning project, as well as others, was promoted by Circuit Cellar based on a 2007 agreement with Echelon.