Hardware Reference
In-Depth Information
Figure 6-8
XBee breakout board, in various stages.
Bottom:
bare board with necessary
headers.
Top right:
finished board.
Top
left:
finished board with XBee mounted.
Mounting the XBee Radios on a Breakout Board
The XBee radios have pins spaced 2mm apart, which is too
narrow to fit on a breadboard. You can either solder wires to
each pin to extend the legs, or you can mount the module on
a breakout board. SparkFun has such a board: the Breakout
Board for XBee Module (part number BOB-08276). Once
you've got the breakout board, solder headers to the inner
rows. These will plug into your breadboard. Next, attach the
2mm female headers. The XBee will plug into these, so you
may find it useful to align them to the board by plugging
them into the XBee first, then plugging it with the headers
attached into the board.
The XBee command protocol is particular about how you
terminate commands, expecting that each command is on
a line terminated only with a carriage return (
\r
or ASCII
13). Most serial terminal programs allow you to control
what is sent when you hit the Return key, however.
+++
Don't hit Return or any other key for at least one second
afterward. The XBee should respond like so:
OK
In CoolTerm for OS X and Windows, click the Options
button and change the Enter Key Emulation to CR (see
Figure 6-10). In PuTTY for Windows and Ubuntu Linux,
choose the Terminal Configuration tab, and check “Implicit
LF in every CR” (see Figure 6-11).
This step is similar to the Bluetooth modem in Chapter 2,
where you typed
$$$
to enter command mode. The XBee
is using an AT-style command set, and the
+++
puts it into
command mode. The one-second pause after this string is
called the
guard time
. If you do nothing, the module will drop
out of command mode after 10 seconds. So, if you're reading
this while typing, you may need to type
+++
again before
the next step.
Once you've configured your serial terminal, open the port
and type:
