Figure 344. Lptim Output Waveform, Continuous Counting Mode Configuration; Timeout Function - ST STM32L4x6 Reference Manual

Low-power timer (LPTIM)
In case an external trigger is selected, an external trigger event arriving after CNTSTRT is
set will start the counter for continuous counting. Any subsequent external trigger event will
be discarded as shown in
In case of software start (TRIGEN[1:0] = '00'), setting CNTSTRT will start the counter for
continuous counting.

Figure 344. LPTIM output waveform, Continuous counting mode configuration

SNGSTRT and CNTSTRT bits can only be set when the timer is enabled (The ENABLE bit
is set to '1'). It is possible to change "on the fly" from One Shot mode to Continuous mode.
If the Continuous mode was previously selected, setting SNGSTRT will switch the LPTIM to
the One Shot mode. The counter (if active) will stop as soon as it reaches ARR.
If the One Shot mode was previously selected, setting CNTSTRT will switch the LPTIM to
the Continuous mode. The counter (if active) will restart as soon as it reaches ARR.
30.4.7

Timeout function

The detection of an active edge on one selected trigger input can be used to reset the
LPTIM counter. This feature is controlled through the TIMOUT bit.
The first trigger event will start the timer, any successive trigger event will reset the counter
and the timer will restart.
A low-power timeout function can be realized. The timeout value corresponds to the
compare value; if no trigger occurs within the expected time frame, the MCU is waked-up by
the compare match event.
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Figure 344.
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