Specifications
XBee®/XBee‐PRO®SERFModules
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IDs) are operating on the same 16-bit PAN ID. If such a conflict is detected, the ZigBee stack can
perform PAN ID conflict resolution to change the 16-bit PAN ID of the network in order to resolve
the conflict. See the ZigBee specification for details.
To summarize, ZigBee routers and end devices should be configured with the 64-bit PAN ID of the
network they want to join. They typically acquire the 16-bit PAN ID when they join a network.
Operating Channel
ZigBee utilizes direct-sequence spread spectrum modulation and operates on a fixed channel. The
802.15.4 PHY defines 16 operating channels in the 2.4 GHz frequency band. XBee modules
support all 16 channels and XBee-PRO modules support 14 of the 16 channels.
ZigBee Application Layers: In Depth
This section provides a more in-depth look at the ZigBee application stack layers (APS, ZDO)
including a discussion on ZigBee endpoints, clusters, and profiles.
Application Support Sublayer (APS)
The APS layer in ZigBee adds support for application profiles, cluster IDs, and endpoints.
Application Profiles
Application profiles specify various device descriptions including required functionality for various
devices. The collection of device descriptions forms an application profile. Application profiles can
be defined as "Public" or "Private" profiles. Private profiles are defined by a manufacturer whereas
public profiles are defined, developed, and maintained by the ZigBee Alliance. Each application
profile has a unique profile identifier assigned by the ZigBee Alliance.
Examples of public profiles include:
• Home Automation
• Smart Energy
• Commercial Building Automation
The Smart Energy profile, for example, defines various device types including an energy service
portal, load controller, thermostat, in-home display, etc. The Smart Energy profile defines required
functionality for each device type. For example, a load controller must respond to a defined
command to turn a load on or off. By defining standard communication protocols and device
functionality, public profiles allow interoperable ZigBee solutions to be developed by independent
manufacturers.
Clusters
A cluster is a related collection of commands and attributes, which together define an interface to
specific functionality. Clusters are used to specify a unique function, service, or action. For
example, the following are some clusters defined in the home automation profile:
• On/Off - Used to switch devices on or off (lights, thermostats, etc.)
• Level Control - Used to control devices that can be set to a level between on and off
• Color Control - Controls the color of color capable devices.
Each cluster has an associated 2-byte cluster identifier (cluster ID). The cluster ID is included in all
application transmissions. Clusters have associated attributes and commands that together define
functionality. For example, a smart energy gateway (service portal) might send a Load Control
Event command to a load controller in order to schedule turning on or off an appliance. Upon
executing the event, the load controller would send a Report Event Status command back to the
gateway.
Devices that operate in an application profile (private or public) must respond correctly to all
required clusters. For example, a light switch that will operate in the home automation public
profile must correctly implement the On/Off and other required clusters in order to interoperate
with other home automation devices. XBee modules implement various clusters in the Digi private