The xBee family of products, made by Digi International, are very useful for short-to-medium range communication. They support Point-to-Point (PtP; P2P) and Point-to-Multi-Point (PtMP; P2MP) communication and have multiple communication modes.
XCTU is the configuration software for the xBee family of products.
https://www.digi.com/products/embedded-systems/digi-xbee/digi-xbee-tools/xctu
To program the xBee modules, use an Explorer board to connect the xBee modules to a USB cable, and then to your computer.
Open XCTU, and click on the “Find a Device” icon at the top left corner. It has the magnifying glass. Then, select the communication port for the module – typically the one labeled “USB Serial Port”. Finally, you’ll select the parameters for that COM port in hopes of the computer to find the module.
If the module has been programmed by somebody else, you might have to use “Select All” to forcibly locate the module. This will take a little longer. Hopefully it’s still configured for the default 9600/8N1N parameters.
When you click “Finish”, XCTU will start probing until it locates a module. Once it does, you’ll click “Add selected devices”.
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The modules will now show up in the left sidebar. Double-clicking a module will load its parameters into the parameter editing window.
At the top of the parameter editing window, the Product Family, Function Set, and Firmware Version are listed.
Note that the function set is Coordinator for the first module and Router/End Device for the second module.
These 2 modules are set up for Point-to-Point “Transparent” mode. For communication to be successful, they must be able to find each other. Generally speaking, all parameters should match between both modules, so that they are essentially cloned other than the destination address.
Simple descriptions for the parameters are given below, while detailed explanations are further down this document.
PAN ID: This number must match on both modules. It identifies the logical Personal Area Network for which the two modules are creating.
Scan Channels: This number should match on both modules.
Destination Address: These 2 fields should be populated with the information from the other module.
Node Identifier: This is a plaintext name or label that you can apply to each module, such as “Controller” and “Rover”.
Power Mode: Boost mode may be turned on or off. It adds a 2dB bump for both TX and RX.
For basic use, everything else can be left as shown below.
Reference Materials
General Document: https://www.digi.com/resources/documentation/Digidocs/90002002/Containers/cont_at_cmds.htm
ID (PAN ID): If set to 0, the coordinator selects a random extended PAN ID, and the router/end device joins any extended PAN ID.
https://www.digi.com/resources/documentation/Digidocs/90002002/Reference/r_cmd_ID.htm
Scan Channels: Coordinator – Bit field list of channels to choose from prior to starting network. Router/End Device – Bit field list of channels scanned to find a Coordinator/Router to join.
https://www.digi.com/resources/documentation/Digidocs/90002002/Reference/r_cmd_SC.htm
Destination Address: When you combine DH with DL, it defines the destination address that the device uses for transmissions in Transparent mode. Special definitions for DH and DL include 0x000000000000FFFF (broadcast) and 0x0000000000000000(coordinator).
https://www.digi.com/resources/documentation/Digidocs/90002002/Reference/r_cmd_DH.htm
https://www.digi.com/resources/documentation/Digidocs/90002002/Reference/r_cmd_DL.htm
Node Identifier: A user-defined name or description of the device. This can be up to 20 ASCII characters.
https://www.digi.com/resources/documentation/Digidocs/90002002/Reference/r_cmd_NI.htm
Power Mode: Enabling boost mode improves the receive sensitivity by 2dB and increase the transmit power by 3dB.
https://www.digi.com/resources/documentation/Digidocs/90002002/Reference/r_cmd_PM.htm