Using Arduino for Prototypes (EE Tip #121)

Arduino is an open-source development kit with a cult following. Open source means the software and hardware design files are available for free download. This begs the question of how the Arduino team can turn a profit, and the answer is the trademark and reputation of the Arduino name and symbol.

Arduino Uno PosterWhile there are now many Arduino clones, the original Arduino boards still outperform most. Arduino is very useful for prototyping. A recent example in my own work is adding a gyroscope sensor to a project. First, I purchased a gyroscope board from Pololu for a small amount. I plugged it into an Arduino breadboard shield purchased from eBay for roughly $5, and wired up the four pins: VCC (3.3 V), GND, SCL, and SDA. Pololu’s website has a link to some demo firmware and I downloaded this from GitHub. The library folders were extracted and renamed according to the instructions and then the example was run. The Arduino serial monitor then showed the gyroscope data in real-time, and the entire process took no more than 30 minutes.

Editor’s note: This EE Tip was written by Fergus Dixon of Sydney, Australia. Dixon runs Electronic System Design, a website set up to promote easy to use and inexpensive development kits. The Arduino Uno pictured above is a small portion of a full Arduino blueprint poster available for free download here.

Client Profile: Digi International, Inc

Contact: Elizabeth Presson

Featured Product: The XBee product family ( is a series of modular products that make adding wireless technology easy and cost-effective. Whether you need a ZigBee module or a fast multipoint solution, 2.4 GHz or long-range 900 MHz—there’s an XBee to meet your specific requirements.

XBee Cloud Kit

Digi International XBee Cloud Kit

Product information: Digi now offers the XBee Wi-Fi Cloud Kit ( for those who want to try the XBee Wi-Fi (XB2B-WFUT-001) with seamless cloud connectivity. The Cloud Kit brings the Internet of Things (IoT) to the popular XBee platform. Built around Digi’s new XBee Wi-Fi
module, which fully integrates into the Device Cloud by Etherios, the kit is a simple way for anyone with an interest in M2M and the IoT to build a hardware prototype and integrate it into an Internet-based application. This kit is suitable for electronics engineers, software designers, educators, and innovators.

Exclusive Offer: The XBee Wi-Fi Cloud Kit includes an XBee Wi-Fi module; a development board with a variety of sensors and actuators; loose electronic prototyping parts to make circuits of your own; a free subscription to Device Cloud; fully customizable widgets to monitor and control connected devices; an open-source application that enables two-way communication and control with the development board over the Internet; and cables, accessories, and everything needed to connect to the web. The Cloud Kit costs $149.

Client Profile: Pololu Robotics

Pololu Robotics
920 Pilot Road
Las Vegas, NV 89119


Pololu Robotics Zumo

Pololu Robotics Zumo

Embedded Products/Services: Pololu designs, manufactures, and distributes a variety of robotic and electronic parts. Get the building blocks for your next project at Pololu, where you can find wheels, motors, motion controllers, basic prototyping supplies, sensors, complete robot kits, and more. Pololu also offers a custom laser cutting service starting at $25.

Product information: The Pololu Zumo robot is an Arduino-controllable tracked robot platform that measures less than 10 cm × 10 cm, which is small enough to qualify for Mini Sumo. The Zumo includes two micro-metal gearmotors coupled to a pair of silicone tracks, a stainless steel bulldozer-style blade, six infrared reflectance sensors for line following or edge detection, a three-axis accelerometer and magnetometer, and a buzzer for simple sounds and music. A kit version is also available.

Exclusive offer: Use coupon code ZUMOCC20 for 20% off any one item in Pololu’s Zumo category (

CC268: The History of Embedded Tech

At the end of September 2012, an enthusiastic crew of electrical engineers and journalists (and significant others) traveled to Portsmouth, NH, from locations as far apart as San Luis Obispo, CA,  and Paris, France, to celebrate Circuit Cellar’s 25th anniversary. Attendees included Don Akkermans (Director, Elektor International Media), Steve Ciarcia (Founder, Circuit Cellar), the current magazine staff, and several well-known engineers, editors, and columnists. The event marked the beginning of the next chapter in the history of this long-revered publication. As you’d expect, contributors and staffers both reminisced about the past and shared ideas about its future. And in many instances, the conversations turned to the content in this issue, which was at that time entering the final phase of production. Why? We purposely designed this issue (and next month’s) to feature a diversity of content that would represent the breadth of coverage we’ve come to deliver during the past quarter century. A quick look at this issue’s topics gives you an idea of how far embedded technology has come. The topics also point to the fact that some of the most popular ’80s-era engineering concerns are as relevant as ever. Let’s review.

In the earliest issues of Circuit Cellar, home control was one of the hottest topics. Today, inventive DIY home control projects are highly coveted by professional engineers and newbies alike. On page 16, Scott Weber presents an interesting GPS-based time server for lighting control applications. An MCU extracts time from GPS data and transmits it to networked devices.

The time-broadcasting device includes a circuit board that’s attached to a GPS module. (Source: S. Weber, CC268)

Thiadmer Riemersma’s DIY automated component dispenser is a contemporary solution to a problem that has frustrated engineers for decades (p. 26). The MCU-based design simplifies component management and will be a welcome addition to any workbench.

The DIY automated component dispenser. (Source: T. Riemersma, CC268)

USB technology started becoming relevant in the mid-to-late 1990s, and since then has become the go-to connection option for designers and end users alike. Turn to page 30 for Jan Axelson’s  tips about debugging USB firmware. Axelson covers controller architectures and details devices such as the FTDI FT232R USB UART controller and Microchip Technology’s PIC18F4550 microcontroller.

Debugging USB firmware (Source: J. Axelson, CC268)

Electrical engineers have been trying to “control time” in various ways since the earliest innovators began studying and experimenting with electric charge. Contemporary timing control systems are implemented in a amazing ways. For instance, Richard Lord built a digital camera controller that enables him to photograph the movement of high-speed objects (p. 36).

Security and product reliability are topics that have been on the minds of engineers for decades. Whether you’re working on aerospace electronics or a compact embedded system for your workbench (p. 52), you’ll want to ensure your data is protected and that you’ve gone through the necessary steps to predict your project’s likely reliability (p. 60).

The issue’s last two articles detail how to use contemporary electronics to improve older mechanical systems. On page 64 George Martin presents a tachometer design you can implement immediately in a machine shop. And lastly, on page 70, Jeff Bachiochi wraps up his series “Mechanical Gyroscope Replacement.” The goal is to transmit reliable data to motor controllers. The photo below shows the Pololu MinIMU-9.

The Pololu MinIMU-9′s sensor axes are aligned with the mechanical gyro so the x and y output pitch and roll, respectively. (Source: J. Bachiochi, CC268)