D-Link DSL-G2452GR User Manual page 120

Section 4 - Configuration
Scheduling a Task
Perform task on Toggle this to perform the specified task on the
schedule schedule specified below.
Simplified Mode
Interval of Specify how often the task should be performed.
execution
Time The time of day (in hours and minutes) to perform
the specified task.
Duration The length of time (measured in days, hours, minutes
and seconds) to wait before executing the task again.
Which fields are available depends on your selection in
the Interval of execution drop-down menu.
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