This document describes the use of the %XMODEMSLEEP and %XT3412 AT commands.
Modem sleep notifications are sent by the %XMODEMSLEEP AT command. They are used to track the nRF9160 modem's inactivity and to receive prewarnings of its predicted activity. During the modem's inactivity, certain hardware components can be deactivated, and hardware resources, such as the antenna or battery, can be used for other purposes. Before the predicted end of sleep or before requesting an operation that requires the use of the modem’s radio resources, the application must activate the components that are needed for LTE connections if they have been switched off to save power during modem inactivity.
Timer T3412 notifications are sent by the %XT3412 AT command. They are used to determine when the modem is expected to transmit. During a timer T3412 period, if the modem is not in Power Saving Mode (PSM), it only monitors pagings and performs cell reselection. A received paging, change of the serving cell, or uplink signaling can interrupt a T3412 period.
The general syntaxes and parameters of the %XMODEMSLEEP and %XT3412 AT commands are described in nRF91 AT Commands Reference Guide.