XBee®/XBee‐PRO® ZB SMT RF Modules
Modes of Operation
Idle Mode
When not receiving or transmitting data, the RF module is in Idle Mode. The module shifts into the other modes
of operation under the following conditions:
•Transmit Mode (Serial data in the serial receive buffer is ready to be packetized)
•Receive Mode (Valid RF data is received through the antenna)
•Sleep Mode (End Devices only)
•Command Mode (Command Mode Sequence is issued, not available with Smart Energy software or when
using the SPI port)
Transmit Mode
When serial data is received and is ready for packetization, the RF module will exit Idle Mode and attempt to
transmit the data. The destination address determines which node(s) will receive the data.
Prior to transmitting the data, the module ensures that a 16-bit network address and route to the destination
node have been established.
If the destination 16-bit network address is not known, network address discovery will take place. If a route is
not known, route discovery will take place for the purpose of establishing a route to the destination node. If a
module with a matching network address is not discovered, the packet is discarded. The data will be transmitted
once a route is established. If route discovery fails to establish a route, the packet will be discarded.
Transmit Mode Sequence
Successful
Transmission
Yes
Yes
16-bit Network
Address Known?
Idle Mode
Route Known?
Transmit Data
New
Transmission
No
No
16-bit Network
Address Discovery
Route Discovery
Yes
Yes
16-bit Network
Address Discovered?
Route Discovered?
No
No
Data Discarded
© 2010 Digi International, Inc.
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DCD [ DIGITAL CORE DESIGN ]
