Murata Electronics North America Z2405HPA Manual Do Utilizador

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ZMN2405/ZMN2405HP Dev Kit 
© 2007-2008 RFM Inc.  
M-2405-0000 Rev. C- 
 
 
Figure 2. Typical ZigBee Network 
2.1  Forming a Network 
The Coordinator is typically the first element powered up. The Coordinator will listen on the first 
channel of the set of channels that has been specified for it to use in forming a network. If the 
Coordinator detects RF energy on that channel, it will move to the next channel in the channel 
set until it finds a clear channel. If a clear channel cannot be found, the Coordinator will indicate 
an error.  
 
If a PAN ID has been specified, the Routers and End Devices will look for a Coordinator with the 
specified PAN ID. If a Coordinator is not found on a channel, or one is found, but has the wrong 
PAN ID, the ZigBee device will go to the next channel on its channel list until a satisfactory 
Coordinator is found. The Coordinator will assign each device that identifies itself to the 
Coordinator a 16-bit network address. This 16-bit network address is used to route data within 
the network. Each ZigBee device has a unique 8-byte MAC address just as in an Ethernet 
network. The 16-bit network address can and will change every time the Coordinator is power 
cycled unless the Static Network mode is enabled. (Refer to Section 2.6 for details).  
 
The network is now formed. If the Routers and End Devices have been configured to transmit 
data on their own, they will begin doing as they have been told. If the Coordinator is to be used 
as a gateway too, it is typically necessary to let the application communicating with the gateway 
to know what devices are on the network. ZigBee provides a discovery command which returns 
from the Coordinator/gateway, the 16-bit network addresses of all devices associated in the 
network. The application then must request the 8-byte MAC address and optionally the “Friendly 
Name” of each device associated with the network. Once the devices associated with the 
network have been discovered and the MAC addresses obtained, the application can address 
data and commands to individual devices on the network.