Wireless modules
It you want to add Wi-Fi and/or Internet connectivity to your design but you aren’t an RF or wireless expert, GainSpan’s All-in-One GS1011M family may be of interest. These wireless modules (see the figure) make it quick, easy, and cost-effective for embedded device and appliance manufacturers to add Wi-Fi to their products. They significantly shorten hardware and software development time and reduce the complexity typically associated with adding Wi-Fi to embedded applications.
The GS1011M modules are FCC certified for the United States and IC certified for Canada. They also have passed pre-certification for ETSI for Europe. They’re are an ideal solution for organizations with limited or no Wi-Fi or RF expertise, as they not only eliminate RF design time but also reduce the burden of testing and certification globally, so designers can focus on their core application and product.
On the software side, adding Wi-Fi connectivity to any embedded device is easy. The modules provide a serial universal asynchronous receiver-transmitted (UART) or serial peripheral interface (SPI), making it possible to connect to any device using an 8/16/32-bit microcontroller (MCU) via a few AT commands. Multiple firmware configurations are available for the stack running on the module.
For applications utilizing a small 8-bit MCU host, the modules support a serial to Wi-Fi function and run the full Wi-Fi and TCP/IP networking stack, completely offloading the host. For applications utilizing more powerful MCUs, the networking stack and services can reside on the host while the module provides all Wi-Fi functionality including security, Wi-Fi Protected Setup (WPS), and provisioning features, for example.
The GainSpan supporting firmware provides features such as personal and enterprise security including WPA2, ad hoc-based Web server provisioning and WPS for simple provisioning of devices with no control buttons or display screen, embedded HTTP Get/Post client for Internet server communication, and over-the-air firmware download. GainSpan recently became Wi-Fi Certified for WPS, which is the industry standard developed by the Wi-Fi Alliance to simplify the process of setting up a secure Wi-Fi network.
The modules operate in the 2.4-GHz band and conform with the IEEE 802.11b standards. They will work in any 802.11b/g/n network and support data rates of 1, 2, 5.5, and 11 Mbits/s. Also, they have an output power of 9 dBm with an internal power amplifier (PA) and 18 dBm with an external PA. Some versions have a printed-circuit board (PCB) trace antenna, but one model is available with a U.FL connector for an external antenna.
The modules are designed to connect to the microcontroller via a UART or SPI (up to 5 Mbits/s). Other interfaces include I2C and general-purpose I/O (GPIO). Additional I/Os include an analog-to-digital converter (ADC), WAKE function, ALARM function, pulse-width modulation (PWM), and JTAG. The power source is 3.3 V dc.
The module family includes four different versions for antenna configuration and output power—internal or external PA and built-in or external antenna. The single-sided modules are designed so they can be soldered on a customer application baseboard.
Modules are sampling now, with production shipments scheduled for September. Evaluation boards and development kits are also available. The modules are competitively priced with products based on other wireless technologies such as ZigBee while offering IP-based connectivity.