The XBee Pro 868 is a long range radio frequency modem that provides up to 80km range with a high gain antenna according to Digi. These devices can form a highly reliable mesh network in both AT and API modes. I have 4 x XBee Pro 868 radios. XBP08-DP is the modem identifier with
the latest firmware, 1061, installed using X-CTU. I chose the default
Function Set, XBEE-PRO 868 SINGLE CHANNEL.
I have tested the 868 automatic routing capabilities which operate at the network layer of the device and are transparent to the user. Routing works extremely well but you must enable it as it is off by default. Digi's Reference Guide for this device when it comes to mesh networking is unhelpful to say the least. In fact, it does not mention the word mesh.
Below I list the series of commands that you need to issue to the radio to configure it to use API mode 2 (API with escape characters) and mesh networking using X-CTU or a terminal emulator (Coolterm is excellent). By default, the 868 modem uses 9600 baud, no parity, 1 stop bit and no flow control for serial port communication.
Put the 868 in AT mode by hitting the + key 3 times within 1 second. It should respond with OK. Issue the following commands in turn and wait the modem to respond with OK after each command.
ATRE # Factory Reset.
ATID 3001 # Give your network an unique ID number, I use 3001.
ATPL0 # Set the lowest power level, 1mW. This is essential in a test environment where several radios are close together.
ATNI ROUTER1 # Give the modem a name, ROUTER1, in this case.
ATNO 2 # Node discovery option 2.
ATAP 2 # Set API mode with escape characters. AT mode is 0 and API mode without escape characters is 1.
ATAO 1 # Set API Option to XBEE DIGIMESH EXPLICIT.
ATWR # Save these settings.
That should get your radios talking API with escape characters to each other in a highly reliable mesh network. You may need to increase the power level out in the field, depending on the range you require.You may wish to issue further commands to further configure the device for higher baud rates, handshaking, encryption (which works well), digital & analog I/O, sleep, etc. The commands are listed in the Digi Reference Guide.
To generate API frames to test connections, visit
http://ftp1.digi.com/support/utilities/digi_apiframes.htmTo test received API frames, install John Foster's excellent packet-check tool,
http://www.jsjf.demon.co.uk/xbee/xbee.htmlGood luck!