Wireless Communication with XBee Radios - Exploring Arduino: Tools and Techniques for Engineering Wizardry - page 223

Figure 11-1: PAN configurations
XBeeRadios
XBee radios can communicate in an application programming interface (API) mode,
and a simple serial pass-through mode. In API mode, they can directly transmit
digital or analog I/O pin states. This enables you to have a microcontroller-free
weather station transmitter, for example. In this chapter, you use the XBees as a
simple serial pass-through. Serial data sent into one radio comes out of another
and vice versa. Using this method, you can use the XBees as a drop-in replace-
ment for a wired serial connection (either between two Arduinos or between an
Arduino and your computer).
XBees have 20 pins and are, for the most part, pin compatible with each
other. This chapter uses Series 1 XBees, which use the 802.15.4 standard. They
are capable of point-to-point and point-to-multipoint communication, but they
do not implement the ZigBee standard, a mesh networking standard found in
Series 2/ZB XBee radios. If you aren't sure what kind of XBees you have, you
probably have Series 1. They look like the ones in Figure 11-2.
Figure 11-2: XBee Series 1 radios