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Step 3 Make the Receiver

Overview

We'll start with the receiver hardware, that's the thing that plugs into the computer and receives data from the wireless power plug. The receiver hardware does 'double duty', it also is used to update the XBee's modems' firmware (which, unfortunately, is necessary because they come from the factory with really old firmware) and configure the modems.

What you'll need

The receiver is essentially, an XBee, with a USB connection to allow a computer to talk to it the XBee.

Name FTDI cable
Description A USB-to-serial converter. Plugs in neatly into the Adafruit XBee adapter to allow a computer to talk to the XBee.
Datasheet TTL-232R 3.3V or 5.0V
Distributor Mouser
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Name Adafruit XBee Adapter kit
Description I'll be using my own design for the XBee breakout/carrier board but you can use nearly any kind as long as you replicate any missing parts such as the3.3V supply and LEDs
You will have 2 adapter kits but you should only assemble one for this part! The other one needs different instructions so just hold off!
Datasheet Webpage
Distributor Adafruit
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Name XBee module
Description We'll be using the XBee "series 1" point-to-multipoint 802.15.4 modules with a chip antenna part # XB24-ACI-001. They're inexpensive and work great. This project most likely won't work with any other version of the XBee, and certainly not any of the 'high power' Pro types!
Datasheet
Distributor Adafruit
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Solder the adapter together!

This step is pretty easy, just go over to the XBee adapter webpage and solder it together according to the instructions!

Remember: You will have 2 adapter kits but you should only solder one of them at this point! The other one needs different instructions so just hold off!

Connect to the XBee

Now its time to connect to the XBees

Find your FTDI cable - use either 3.3V or 5V. These cables have a USB to serial converter chip molded into them and are supported by every OS. Thus configuring or upgrading or connecting is really trivial. Simply plug the cable into the end of the module so that the black wire lines up with GND. There is a white outline showing where the cable connects.

You'll need to figure out which serial port (COM) you are using. Plug in the FTDI cable, USB adapter, Arduino, etc. Under Windows, check the device manager, look for "USB Serial Port"

Digi/Maxstream wrote a little program to help configure XBees, its also the only way I know of to upgrade them to the latest firmware. Unfortunately it only runs on Windows. Download X-CTU from Digi and install it on your computer

After installing and starting the program, select the COM port (COM4 here) and baud rate (9600 is default). No flow control, 8N1. Make sure the connection box looks just like the image (other than the com port which may be different)

To verify, click Test / Query

Hopefully the test will succeed. If you are having problems: check that the XBee is powered, the green LED on the adapter board should be blinking, the right COM port & baud rate is selected, etc.

Now unplug the adapter from the FTDI cable, carefully replace the first XBee with the other one and make sure that one is talking fine too. Once you know both XBees are working with the adapter, its time to upgrade and configure them, the next step!