Specifications
XBee®/XBee‐PRO®SERFModules
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In the figure above, t1, t2, and t3 represent the following events:
• T1 - Time when the module wakes from cyclic sleep
• T2 - Time when the module returns to sleep
• T3 - Later time when the module wakes from cyclic sleep.
The wake time and sleep time are configurable with software commands as described in the
sections below.
Wake Time (Until Sleep)
In cyclic sleep mode (SM=4 or 5), if serial or RF data is received, the module will start a sleep
timer (time until sleep). Any data received serially or over the RF link will restart the timer. The
sleep timer value is settable with the ST command. While the module is awake, it will send poll
request transmissions to check its parent for buffered data messages. The module returns to sleep
when the sleep timer expires, or if the SI command is sent to it. The following image shows this
behavior.