Specifications
XBee®/XBee‐PRO®SERFModules
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When data is transmitted from one node to another, a network-level acknowledgement is
transmitted back across the established route to the source node. This acknowledgement packet
indicates to the source node that the data packet was received by the destination node. If a
network acknowledgement is not received, the source node will re-transmit the data.
It is possible in rare circumstances for the destination to receive a data packet, but for the source
to not receive the network acknowledgment. In this case, the source will retransmit the data,
which could cause the destination to receive the same data packet multiple times. The XBee
modules do not filter out duplicate packets. The application should include provisions to address
this potential issue.
See Data Transmission and Routing in chapter 4 for more information.
Receive Mode
If a valid RF packet is received, the data is transferred to the serial transmit buffer.
Sleep Mode
Sleep modes allow the end device to enter states of low power consumption when not in use. The
end device supports support both pin sleep (sleep mode entered on pin transition) and cyclic sleep
(module sleeps for a fixed time). XBee sleep modes are discussed in detail in chapter 6.