XBee®/XBee‐PRO® ZB SMT RF Modules
SD
ZS
Set the scan duration period. This value determines how long the coordinator performs an energy scan or
PAN ID scan on a given channel.
Set the ZigBee stack profile for the network.
EE
NK
Enable or disable security in the network.
Set the network security key for the network. If set to 0 (default), a random network security key will be
used.
KY
EO
Set the trust center link key for the network. If set to 0 (default), a random link key will be used.
Set the security policy for the network.
Once the coordinator starts a network, the network configuration settings and child table data persist through
power cycles as mentioned in the "Persistent Data" section.
When the coordinator has successfully started a network, it
• Allows other devices to join the network for a time (see NJ command)
• Sets AI=0
• Starts blinking the Associate LED
• Sends an API modem status frame ("coordinator started") out the serial port when using API mode.
These behaviors are configurable using the following commands:
Command
Description
NJ
Sets the permit-join time on the coordinator, measured in seconds.
D5
LT
Enables the Associate LED functionality.
Sets the Associate LED blink time when joined. Default is 1 blink per
second.
If any of the command values in the network formation commands table changes, the coordinator will leave its
current network and start a new network, possibly on a different channel. Note that command changes must be
applied (AC or CN command) before taking effect.
Permit Joining
The permit joining attribute on the coordinator is configurable with the NJ command. NJ can be configured to
always allow joining, or to allow joining for a short time.
Joining Always Enabled
If NJ=0xFF (default), joining is permanently enabled. This mode should be used carefully. Once a network
has been deployed, the application should strongly consider disabling joining to prevent unwanted joins
from occurring.
Joining Temporarily Enabled
If NJ < 0xFF, joining will be enabled only for a number of seconds, based on the NJ parameter. The timer is
started once the XBee joins a network. Joining will not be re-enabled if the module is power cycled or reset.
The following mechanisms can restart the permit-joining timer:
• Changing NJ to a different value (and applying changes with the AC or CN commands)
• Pressing the commissioning button twice
• Issuing the CB command with a parameter of 2
The last two cases enable joining for one minute if NJ is 0x0 or 0xFF. Otherwise, the commissioning button
and the CB2 command enable joining for NJ seconds.
Resetting the Coordinator
When the coordinator is reset or power cycled, it checks its PAN ID, operating channel and stack profile against
the network configuration settings (ID, CH, ZS). It also verifies the saved security policy against the security
configuration settings (EE, NK, KY). If the coordinator's PAN ID, operating channel, stack profile, or security
© 2010 Digi International, Inc.
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DCD [ DIGITAL CORE DESIGN ]
