Low-Power Micromodule

The ECM-DX2 is a highly integrated, low-power consumption micromodule. Its fanless operation and extended temperature are supported by the DMP Vortex86DX2 system-on-a-chip (SoC) CPU. The micromodule is targeted for industrial automation, transportation/vehicle construction, and aviation applications.
The ECM-DX2 withstands industrial operation environments for –40-to-75°C temperatures and supports 12-to-26-V voltage input. Multiple OSes, including Windows 2000/XP and Linux, can be used in a variety of embedded designs.

AvalueThe micromodule includes on-board DDR2 memory that supports up to 32-bit, 1-GB, and single-channel 24-bit low-voltage differential signaling (LVDS) as well as video graphics array (VGA) + LVDS or VGA + TTL multi-display configurations. The I/O deployment includes one SATA II interface, four COM ports, two USB 2.0 ports, 8-bit general-purpose input/output (GPIOs), two Ethernet ports, and one PS/2 connector for a keyboard and a mouse. The ECM-DX2 also provides a PC/104 expansion slot and one MiniPCIe card slot.

Contact Avalue Technology for pricing.

Avalue Technology, Inc.
www.avalue.com.tw

ARM mbed Platform for Bluetooth Smart Applications

OLYMPUS DIGITAL CAMERAThe nRF51822-mKIT simplifies and accelerates the prototyping process for Bluetooth Smart sensors connecting to the Internet of Things (IoT). The platform is designed for fast, easy, and flexible development of Bluetooth Smart applications.

The nRF51822 system-on-chip (SoC) combines a Bluetooth v4.1-compliant 2.4-GHz multiprotocol radio with an ARM Cortex-M0 CPU core on a single chip optimized for ultra-low-power operation. The SoC simplifies and accelerates the prototyping process for Bluetooth Smart sensors connecting to the IoT.

The nRF51822-mKIT’s features include a Bluetooth Smart API, 31 pin-assignable general-purpose input/output (GPIO), a CMSIS-DAP debugger, Programmable Peripheral Interconnect (PPI), and the ability to run from a single 2032 coin-cell battery.

Through mbed, the kit is supported by a cloud-based approach to writing code, adding libraries, and compiling firmware. A lightweight online IDE operates on all popular browsers running on Windows, Mac OSX, iOS, Android, and Linux OSes. Developers can use the kit to access a cloud-based ARM RVDS 4.1 compiler that optimizes code size and performance.

The nRF51822-mKIT costs $59.95.

Nordic Semiconductor ASA
www.nordicsemi.com

Remote Control and Monitoring of Household Devices

Raul Alvarez, a freelance electronic engineer from Bolivia, has long been interested in wireless device-to-device communication.

“So when the idea of the Internet of Things (IoT) came around, it was like rediscovering the Internet,” he says.

I’m guessing that his dual fascinations with wireless and the IoT inspired his Home Energy Gateway project, which won second place in the 2012 DesignSpark chipKIT challenge administered by Circuit Cellar.

“The system enables users to remotely monitor their home’s power consumption and control household devices (e.g., fans, lights, coffee machines, etc.),” Alvarez says. “The main system consists of an embedded gateway/web server that, aside from its ability to communicate over the Internet, is also capable of local communications over a home area wireless network.”

Alvarez catered to his interests by creating his own wireless communication protocol for the system.

“As a learning exercise, I specifically developed the communication protocol I used in the home area wireless network from scratch,” he says. “I used low-cost RF transceivers to implement the protocol. It is simple and provides just the core functionality necessary for the application.”

Figure1: The Home Energy Gateway includes a Hope Microelectronics RFM12B transceiver, a Digilent chipKIT Max32 board, and a Microchip Technology ENC28J60 Ethernet controller chip.

Figure 1: The Home Energy Gateway includes a Hope Microelectronics RFM12B transceiver, a Digilent chipKIT Max32 board, and a Microchip Technology ENC28J60 Ethernet controller chip.

Alvarez writes about his project in the February issue of Circuit Cellar. His article concentrates on the project’s TCI/IP communications aspects and explains how they interface.

Here is his article’s overview of how the system functions and its primary hardware components:

Figure 1 shows the system’s block diagram and functional configuration. The smart meter collects the entire house’s power consumption information and sends that data every time it is requested by the gateway. In turn, the smart plugs receive commands from the gateway to turn on/off the household devices attached to them. This happens every time the user turns on/off the controls in the web control panel.

Photo 1: These are the three smart node hardware prototypes: upper left,  smart plug;  upper right, a second smart plug in a breadboard; and at bottom,  the smart meter.

Photo 1: These are the three smart node hardware prototypes: upper left, smart plug; upper right, a second smart plug in a breadboard; and at bottom, the smart meter.

I used the simple wireless protocol (SWP) I developed for this project for all of the home area wireless network’s wireless communications. I used low-cost Hope Microelectronics 433-/868-/915-MHz RFM12B transceivers to implement the smart nodes. (see Photo 1)
The wireless network is configured to work in a star topology. The gateway assumes the role of a central coordinator or master node and the smart devices act as end devices or slave nodes that react to requests sent by the master node.

The gateway/server is implemented in hardware around a Digilent chipKIT Max32 board (see Photo 2). It uses an RFM12B transceiver to connect to the home area wireless network and a Microchip Technology ENC28J60 chip module to connect to the LAN using Ethernet.

As the name implies, the gateway makes it possible to access the home area wireless network over the LAN or even remotely over the Internet. So, the smart devices are easily accessible from a PC, tablet, or smartphone using just a web browser. To achieve this, the gateway implements the SWP for wireless communications and simultaneously uses Microchip Technology’s TCP/IP Stack to work as a web server.

Photo 2: The Home Energy Gateway’s hardware includes a Digilent chipKIT Max32 board and a custom shield board.

Photo 2: The Home Energy Gateway’s hardware includes a Digilent chipKIT Max32 board and a custom shield board.

Thus, the Home Energy Gateway generates and serves the control panel web page over HTTP (this page contains the individual controls to turn on/off each smart plug and at the same time shows the power consumption in the house in real-time). It also uses the wireless network to pass control data from the user to the smart plugs and to read power consumption data from the smart meter.

The hardware module includes three main submodules: The chipKIT Max 32 board, the RFM12B wireless transceiver, and the ENC28J60 Ethernet module. The smart meter hardware module has an RFM12B transceiver for wireless communications and uses an 8-bit Microchip Technology PIC16F628A microcontroller as a main processor. The smart plug hardware module shows the smart plugs’ main hardware components and has the same microcontroller and radio transceiver as the smart meter. But the smart plugs also have a Sharp Microelectronics S212S01F solid-state relay to turn on/off the household devices.

On the software side, the gateway firmware is written in C for the Microchip Technology C32 Compiler. The smart meter’s PIC16F628A code is written in C for the Hi-TECH C compiler. The smart plug software is very similar.

Alvarez says DIY home-automation enthusiasts will find his prototype inexpensive and capable. He would like to add several features to the system, including the ability to e-mail notifications and reports to users.

For more details, check out the February issue now available for download by members or single-issue purchase.

Turn Your Android Device into an Application Tool

A few years ago, the Android Open Accessory initiative was announced with the aim of making it easier for hardware manufacturers to create accessories that work with every Android device. Future Technology Devices International (FTDI) joined the initiative and last year introduced the FTD311D multi-interface Android host IC. The goal was to enable engineers and designers to make effective use of tablets and smartphones with the Android OS, according to Circuit Cellar columnist Jeff Bachiochi.

The FTD311D “provides an instant bridge from an Android USB port(B) to peripheral hardware over general purpose input-out (GPIO), UART, PWM, I2C Master, SPI Slave, or SPI Master interfaces,” Bachiochi says.

In the magazine’s December issue Bachiochi takes a comprehensive look at the USB Android host IC and how it works. By the end of his article, readers will have learned quite a bit about how to use FTDI’s apps and the FT311D chip to turn an Android device into their own I/0 tool.

Bachiochi used the SPI Master demo to read key presses and set LED states on this SPI slave 16-key touch panel.

Bachiochi used the SPI Master demo to read key presses and set LED states on this SPI slave 16-key touch panel.

Here is how Bachiochi describes the FT311D and its advantages:

The FT311D is a full-speed USB host targeted at providing access to peripheral hardware from a USB port on an Android device. While an Android device can be a USB host, many are mobile devices with limited power. For now, these On-The-Go (OTG) ports will be USB devices only (i.e., they can only connect to a USB host as a USB device).

Since the USB host is responsible for supplying power to a USB peripheral device, it would be bad design practice to enable a USB peripheral to drain an Android mobile device’s energy. Consequently, the FT311D takes on the task of USB host, eliminating any draw on the Android device’s battery.

All Android devices from V3.1 (Honeycomb) support the Android Open Accessory Mode (AOAM). The AOAM is the complete reverse of the conventional USB interconnect. This game-changing approach to attaching peripherals enables three key advantages. First, there is no need to develop special drivers for the hardware; second, it is unnecessary to root devices to alter permissions for loading drivers; and third, the peripheral provides the power to use the port, which ensures the mobile device battery is not quickly drained by the external hardware being attached.

Since the FT311D handles the entire USB host protocol, USB-specific firmware programming isn’t required. As the host, the FT311D must inquire whether the connected device supports the AOAM. If so, it will operate as an Open Accessory Mode device with one USB BULK IN endpoint and one USB BULK OUT endpoint (as well as the control endpoint.) This interface will be a full-speed (12-Mbps) USB enabling data transfer in and out.

The AOAM USB host has a set of string descriptors the Android OS is capable of reading. These strings are (user) associated with an Android OS application. The Android then uses these strings to automatically start the application when the hardware is connected. The FT311D is configured for one of its multiple interfaces via configuration inputs at power-up. Each configuration will supply the Android device with a unique set of string descriptors, therefore enabling different applications to run, depending on its setup.

The FT311D’s configuration determines whether each application will have access to several user interface APIs that are specific to each configuration.

The article goes on to examine the various interfaces in detail and to describe a number of demo projects, including a multimeter.

Many of Bachiochi's projects use printable ASCII text commands and replies. This enables a serial terminal to become a handy user I/O device. This current probe circuit outputs its measurements in ASCII-printable text.

Many of Bachiochi’s projects use printable ASCII text commands and replies. This enables a serial terminal to become a handy user I/O device. This current probe circuit outputs its measurements in ASCII-printable text.

Multimeters are great tools. They have portability that enables them to be brought to wherever a measurement must be made. An Android device has this same ability. Since applications can be written for these devices, they make a great portable application tool. Until the AOAM’s release, there was no way for these devices to be connected to any external circuitry and used as an effective tool.

I think FTDI has bridged this gap nicely. It provided a great interface chip that can be added to any circuit that will enable an Android device to serve as an effective user I/O device. I’ve used the chip to quickly interface with some technology to discover its potential or just test its abilities. But I’m sure you are already thinking about the other potential uses for this connection.

Bachiochi is curious to hear from readers about their own ideas.

If you think the AOAM has future potential, but you want to know what’s involved with writing Android applications for a specific purpose, send me an e-mail and I’ll add this to my list of future projects!

You can e-mail Bachiochi at jeff.bachiochi@imaginethatnow.com or post your comment here.

 

Scott Garman, Technical Evangelist

This article was a preview of an upcoming interview in the February issue of Circuit Cellar. The full interview is now available here.
Garman_web

Scott Garman is a Portland, OR-based Linux software engineer. Scott is very involved with the Yocto Project, an open-source collaboration that provides tools for the embedded Linux industry. Scott tells us about how he recently helped Intel launch MinnowBoard, the company’s first open-hardware SBC. The entire interview will be published in Circuit Cellar’s February issue.—Nan Price, Associate Editor

NAN: What is the Yocto Project?

 SCOTT: The Yocto Project is centered on the OpenEmbedded build system, which offers a tremendous amount of flexibility in how you can create embedded Linux distros. It gives you the ability to customize nearly every policy of your embedded Linux system.

I’ve developed training materials for new developers getting started with the Yocto Project, including “Getting Started with the Yocto Project—New Developer Screencast Tutorial.”

MinnowBoardWEB

Scott was involved with a MinnowBoard robotics and computer vision demo at LinuxCon Japan, May 2013.

NAN: Tell us about Intel’s recently introduced the MinnowBoard SBC.

SCOTT: The MinnowBoard is based on Intel’s Queens Bay platform, which pairs a Tunnel Creek Atom CPU (the E640 running at 1 GHz) with the Topcliff Platform controller hub. The board has 1 GB of RAM and includes PCI Express, which powers our SATA disk support and gigabit Ethernet. It’s an SBC that’s well suited for embedded applications that can use that extra CPU and especially I/O performance.

MinnowBoardOWI_web

Scott worked on a MinnowBoard demo built around an OWI Robotic Arm.

The MinnowBoard also has embedded bus standards including GPIO, I2C, SPI, and even CAN (used in automotive applications) support. We have an expansion connector on the board where we route these buses, as well as two lanes of PCI Express for custom high-speed I/O expansion.

NAN: What compelled Intel to make the MinnowBoard open hardware?

SCOTT: The main motivation for the MinnowBoard was to create an affordable Atom-based development platform for the Yocto Project. We also felt it was a great opportunity to try to release the board’s design as open hardware.