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.htm
To test received API frames, install John Foster's excellent packet-check
tool, http://www.jsjf.demon.co.uk/xbee/xbee.html

Good luck!

My thanks to Kevin J. Walsh for the above mesh config!

Hi there!

first of all: thank you very much for sharing this little howto!

I am currently working in a research project where we need to build up a mesh network with nodes which have good penetration characteristics in massive buildings. I bought some XBee PRO 868 modules and I am quite impressed of the good ranges I have in our building. To further increase the range and coverage I need multihopping capabilities.

I am just wondering: what is exactly the difference of Digimesh and Digimesh explicit?

In your howto, you recommend the 'explicit option. Is this necessary to enable the mesh (I.e. multihop) features of the XBee PRO XBee 868?

Thanks in advance,

Matt

I have not used the 868 modules so can't help there. Try the project
google groups page as there have been several users that have posted
on 868. Also haven't used digimesh. I recommend contacting digi
support. They have been quite responsive in the past and should be
able to help you out. Good luck!

Andrew