Anatomy of the XBee
If you look at an XBee module, shown in Figure 4.3, it looks like a blue plate the size of a postage stamp, with a number of metal pins sticking out underneath. The top features an antenna. Adding it to a breakout board makes for more detail, so let’s go through the XBee’s various features.
FIGURE 4.3 The XBee and its breakout board breadboarded up. Note that the 5V and GND pins are already connected to the proper terminal buses.
- Pins—You can see the tops of the XBee’s pins. They control the board, bringing in power and sending and receiving data from the Arduino. The pins plug into headers on the breakout board. Note that these pins have the wrong spacing for breadboards.
- Antenna—You have multiple antenna options depending on the XBee, but I think this wire antenna is the best for what it does, because it’s tough and can take a modest amount of abuse without bending.
- Power LED—This lights when the board powers up.
- Data LED—This flashes to let you know that data is passing through the XBee.
- Power regulator—These capacitors and the transistor manage the power going into the XBee. Unfortunately, frying a radio by using too much power is easy to do. The good news is that the regulator keeps the power flowing at just the right voltage.
- Breadboard pins—Unlike the pins that connect the XBee to the breakout board, these pins are spaced correctly for a breadboard. Just as good, they are labeled so you can see which pin does what!