XBees - Arduino - page 92

■ Note Creating a network bridge is possible by connecting two different series, which converts between network

types.

Simple Setup
This section's example sets up a simple communication for a set of series 2 XBee modules. There is some software
that needs to be set up before the XBees can start communicating. Unlike series 1 modules, which can be configured
for communications via a serial terminal, series 2 modules need different firmware for different nodes on the XBee
network. There are two different software packages that can perform the firmware configuration.:

• X-CTU : This is the Digi proprietary software package to program the XBee modules. The
software is available from the Digi web site, as well as directly from http://ftp1.digi.com/
support/utilities/40003002_B.exe . The X-CTU is capable of running on other operating
systems, such as Linux via WINE. You need to download the firmware ZIP file for series 2
devices if setting up the X-CTU on Linux. You can download it from www.digi.com/support/p
roductdetail?pid=3430&type=drivers . You also need to define a link so the WINE software
can use ttyUSB to create a link; to do so, type the following into a command shell:

ln -s /dev/ttyUSB0 ~/.wine/dosdevices/com1

• Moltosenso : This software package is made by a third-party vendor and has the same
functionality as the X-CTU. It natively works on the three common operating systems, Linux,
Mac, and Windows, and is available at www.moltosenso.com . This software may be a bit
buggy on some 64-bit Linux distributions. The ZIP files that contain the firmware have to
be downloaded from Digi. Be aware that this software does not automatically determine
the firmware that is compatible with the connected XBee module, but will work well for
configuring the module's other settings.

When the XBee is loaded with the AT firmware, a serial terminal program such as minicom, PuTTY, or
HyperTerminal can be used to set and read options.
There are two different communication modes that the XBee module can be set to via different firmware:

• Transparent mode : Also known as AT command mode , transparent mode acts as a direct
serial connection, the same way hardwired connections work. Sensors like the Parallax RFID
readers can be connected over XBees in transparent mode without any other microcontroller
in between the sensor and the RF module. This mode provides a great method for direct
XBee-to-XBee communications and is useful in instances where the user needs to change
settings while a network is up and running. You can enter this mode by typing +++ without a
carriage return into a serial program and waiting for an OK to return. All the commands are two
characters prefixed by AT and followed by a carriage return. An example is the command ATSL ,
which will print the lower four bytes of the module's serial number.

• API mode : This is useful for lager dynamic network setups where the software or
microcontroller can easily change configurations without having to convert the
human-readable AT command mode. API has a predefined protocol and communicates via
packets. The use of the API mode is discussed further on in this chapter.