The Wireless shield allows an Arduino board to communicate wirelessly using a wireless module. It is based on the Xbee modules from Digi, but can use any module with the same footprint. The module can communicate up to 100 feet indoors or 300 feet outdoors (with line-of-sight). It can be used as a serial/usb replacement or you can put it into a command mode and configure it for a variety of broadcast and mesh networking options. The shields breaks out each of the Xbee's pins to a through-hole solder pad.
Included on board is a SD card slot. When using the SD Library to access the card, Pin 4 is CS and cannot be used otherwise. SPI also relies on pins 11, 12, and 13 for communication.
Also on board is a switch allowing for control via USB or the microcontroller.
EAGLE files: arduino_WirelessShield_SD_v3-reference-design.zip
The Wireless shield has an onboard switch labelled Micro and USB. This determine how the Xbee's serial communication connects to the serial communication between the microcontroller (ATmega8 or ATmega168) and USB-to-serial chip on the Arduino board.
The Wireless shield can be used with different modules with the same footprint as the XBee modules. The instructions below are for the XBee 802.15.4 modules (sometimes called "Series 1" to distinguish them from the Series 2 modules, although "Series 1" doesn't appear in the official name or product description) and also for the XBee ZNet 2.5 or XBee ZB modules, both known as "Series 2" modules. All the modules, basically have the same type of configuration parameters, but differ by the function that they implement and the topologies of networks that they can create. Can communicate with each other only modules of the same family.
There are multiple parameters that need to be configured correctly for two modules to talk to each other (although with the default settings, all modules should be able to talk to each other). They need to be on the same network, as set by the ID parameter (see "Configuration" below for more details on the parameters). The modules need to be on the same channel, as set by the CH parameter. Finally, a module's destination address (DH and DL parameters) determine which modules on its network and channel will receive the data it transmits. This can happen in a few ways:
Again, this address matching will only happen between modules on the same network and channel. If two modules are on different networks or channels, they can't communicate regardless of their addresses.
For the "Series 2" modules you must chose which
firmware put on the module to give it Coordinator, Router or End Device
functionality. Series 2 use only serial low (
SL) and serial high (
SH) for addressing.
Here are some of the more useful parameters for configuring your Xbee module. For step-by-step instructions on reading and writing them using AT commands, see the:
Make sure to prepend
AT to the parameter name when sending a command to the module (e.g. to read the
ID parameter, you should send the command
|Command||Description||Valid Values||Default Value|
| ||The network ID of the XBee module.||0 - 0xFFFF||3332|
| ||The channel of the XBee module.||0x0B - 0x1A||0X0C|
| || The serial number of the XBee module (|| 0 - 0xFFFFFFFF |
|different for each module|
| ||The 16-bit address of the module.||0 - 0xFFFF||0|
| || The destination address for wireless communication (|| 0 - 0xFFFFFFFF |
| 0 (for both |
| ||The baud rate used for serial communication with the Arduino board or computer.|| 0 (1200 bps) |
1 (2400 bps)
2 (4800 bps)
3 (9600 bps)
4 (19200 bps)
5 (38400 bps)
6 (57600 bps)
7 (115200 bps)
|3 (9600 baud)|
Note: although the valid and default values in the table above are written with a prefix of "0x" (to indicate that they are hexadecimal numbers), the module will not include the "0x" when reporting the value of a parameter, and you should omit it when setting values.
Here are a couple more useful commands for configuring the XBee module (you'll need to prepend
AT to these too).
| || Restore factory default settings (note that like parameter changes, this is not permanent unless followed by the ||
| ||Write newly configured parameter values to non-volatile (long-term) storage. Otherwise, they will only last until the module loses power.||
| || Exit command mode now. (If you don't send any
commands to the module for a few seconds, command mode will timeout and
exit even without a ||