Specifications
XBee®/XBee‐PRO®SERFModules
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payload information instead of using command mode to modify addresses. The module will send
data frames to the application containing status packets; as well as source, and payload
information from received data packets.
The API operation option facilitates many operations such as the examples cited below:
• Transmitting data to multiple destinations without entering Command Mode
• Receive success/failure status of each transmitted RF packet
• Identify the source address of each received packet.
RF modules that contain the following firmware versions will support API operation: 31xx (API
Coordinator), 33xx (API Router), and 39xx (API end device).
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)
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.