ZigBee networks
Zigbee application layers: in depth
XBee/XBee-PRO® S2C ZigBee® RF Module
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Home automation
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Smart Energy
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Commercial building automation
For example, the Smart Energy profile defines various device types including an energy service portal,
load controller, thermostat, in-home display, and so on. 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.
Digi XBee ZigBee firmware operates on a private profile called the Digi Drop-In Networking profile.
However, in many cases the XBee/XBee-PRO ZigBee RF Module can use API mode to talk to devices in
public profiles or non-Digi private profiles. For more information, see
.
Clusters
A cluster is an application message type defined within a profile. You can use clusters to specify a
unique function, service, or action. The following examples are some clusters defined in the home
automation profile:
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On/Off - Used to switch devices on or off (lights, thermostats, etc.)
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Level Control - Used to control devices that can be set to a level between on and off
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Color Control - Controls the color of color capable devices
Each cluster has an associated 2-byte cluster identifier (cluster ID). All application transmissions
include the cluster ID. Clusters often have associated request and response messages. For example, a
smart energy gateway (service portal) might send a load control event to a load controller in order to
schedule turning on or off an appliance. Upon executing the event, the load controller sends a load
control report message 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 operates 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. The ZigBee Alliance has defined a ZigBee Cluster Library (ZCL) that contains
definitions or various general use clusters that could be implemented in any profile.
XBee modules implement various clusters in the Digi private profile. You can also use the API to send
or receive messages on any cluster ID (and profile ID or endpoint). For more information, see
Endpoints
The APS layer includes supports for endpoints. An endpoint can be thought of as a running application,
similar to a TCP/IP port. A single device can support one or more endpoints. A 1- byte value identifies
each application endpoint, ranging from 1 to 240. Each defined endpoint on a device is tied to an
application profile. A device could, for example, implement one endpoint that supports a Smart Energy
load controller, and another endpoint that supports other functionality on a private profile.
ZigBee device profile
Profile ID 0x0000 is reserved for the ZigBee Device Profile. This profile is implemented on all ZigBee
devices. Device Profile defines many device and service discovery features and network management
capabilities. Endpoint 0 is a reserved endpoint that supports the ZigBee Device Profile. This endpoint is
called the ZigBee Device Objects (ZDO) endpoint.