Digi International Inc XBEEPRO2 Manual Do Utilizador
XBee®/XBee‐PRO® ZB RF Modules
© 2011 Digi International, Inc.
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A router has the following characteristics: it
•Must join a ZigBee PAN before it can transmit, receive, or route data
•After joining, can allow routers and end devices to join the network
•After joining, can assist in routing data
•Cannot sleep--should be mains powered.
•Can buffer RF data packets for sleeping end device children.
•After joining, can allow routers and end devices to join the network
•After joining, can assist in routing data
•Cannot sleep--should be mains powered.
•Can buffer RF data packets for sleeping end device children.
An end device has the following characteristics: it
•Must join a ZigBee PAN before it can transmit or receive data
•Cannot allow devices to join the network
•Must always transmit and receive RF data through its parent. Cannot route data.
•Can enter low power modes to conserve power and can be battery-powered.
•Cannot allow devices to join the network
•Must always transmit and receive RF data through its parent. Cannot route data.
•Can enter low power modes to conserve power and can be battery-powered.
An example of such a network is shown below:
In ZigBee networks, the coordinator must select a PAN ID (64-bit and 16-bit) and channel to start a network.
After that, it behaves essentially like a router. The coordinator and routers can allow other devices to join the
network and can route data.
After that, it behaves essentially like a router. The coordinator and routers can allow other devices to join the
network and can route data.
After an end device joins a router or coordinator, it must be able to transmit or receive RF data through that
router or coordinator. The router or coordinator that allowed an end device to join becomes the "parent" of the
end device. Since the end device can sleep, the parent must be able to buffer or retain incoming data packets
destined for the end device until the end device is able to wake and receive the data.
router or coordinator. The router or coordinator that allowed an end device to join becomes the "parent" of the
end device. Since the end device can sleep, the parent must be able to buffer or retain incoming data packets
destined for the end device until the end device is able to wake and receive the data.
PAN ID
ZigBee networks are called personal area networks or PANs. Each network is defined with a unique PAN
identifier (PAN ID). This identifier is common among all devices of the same network. ZigBee devices are either
preconfigured with a PAN ID to join, or they can discovery nearby networks and select a PAN ID to join.
identifier (PAN ID). This identifier is common among all devices of the same network. ZigBee devices are either
preconfigured with a PAN ID to join, or they can discovery nearby networks and select a PAN ID to join.
ZigBee supports both a 64-bit and a 16-bit PAN ID. Both PAN IDs are used to uniquely identify a network.
Devices on the same ZigBee network must share the same 64-bit and 16-bit PAN IDs. If multiple ZigBee
networks are operating within range of each other, each should have unique PAN IDs.
Devices on the same ZigBee network must share the same 64-bit and 16-bit PAN IDs. If multiple ZigBee
networks are operating within range of each other, each should have unique PAN IDs.
The 16-bit PAN ID is used as a MAC layer addressing field in all RF data transmissions between devices in a
network. However, due to the limited addressing space of the 16-bit PAN ID (65,535 possibilities), there is a
possibility that multiple ZigBee networks (within range of each other) could use the same 16-bit PAN ID. To
resolve potential 16-bit PAN ID conflicts, the ZigBee Alliance created a 64-bit PAN ID.
network. However, due to the limited addressing space of the 16-bit PAN ID (65,535 possibilities), there is a
possibility that multiple ZigBee networks (within range of each other) could use the same 16-bit PAN ID. To
resolve potential 16-bit PAN ID conflicts, the ZigBee Alliance created a 64-bit PAN ID.
The 64-bit PAN ID (also called the extended PAN ID), is intended to be a unique, non-duplicated value. When a
coordinator starts a network, it can either start a network on a preconfigured 64-bit PAN ID, or it can select a
random 64-bit PAN ID. The 64-bit PAN ID is used during joining; if a device has a preconfigured 64-bit PAN ID,
it will only join a network with the same 64-bit PAN ID. Otherwise, a device could join any detected PAN and
inherit the PAN ID from the network when it joins. The 64-bit PAN ID is included in all ZigBee beacons and is
used in 16-bit PAN ID conflict resolution.
coordinator starts a network, it can either start a network on a preconfigured 64-bit PAN ID, or it can select a
random 64-bit PAN ID. The 64-bit PAN ID is used during joining; if a device has a preconfigured 64-bit PAN ID,
it will only join a network with the same 64-bit PAN ID. Otherwise, a device could join any detected PAN and
inherit the PAN ID from the network when it joins. The 64-bit PAN ID is included in all ZigBee beacons and is
used in 16-bit PAN ID conflict resolution.
Routers and end devices are typically configured to join a network with any 16-bit PAN ID as long as the 64-bit
PAN ID is valid. Coordinators typically select a random 16-bit PAN ID for their network.
PAN ID is valid. Coordinators typically select a random 16-bit PAN ID for their network.
Since the 16-bit PAN ID only allows up to 65,535 unique values, and since the 16-bit PAN ID is randomly
selected, provisions exist in ZigBee to detect if two networks (with different 64-bit PAN IDs) are operating on
selected, provisions exist in ZigBee to detect if two networks (with different 64-bit PAN IDs) are operating on