ST STM32L4+ Series Reference Manual page 1517

RM0432
42.5 LPTIM low-power modes
Mode
Sleep
Stop
Standby
42.6 LPTIM interrupts
The following events generate an interrupt/wake-up event, if they are enabled through the
LPTIM_IER register:
•
Compare match
• Auto-reload match (whatever the direction if encoder mode)
•
External trigger event
•
Autoreload register write completed
•
Compare register write completed
•
Direction change (encoder mode), programmable (up / down / both).
•
Update Event
•
Repetition register update OK
Note: If any bit in the LPTIM_IER register (Interrupt Enable Register) is set after that its
corresponding flag in the LPTIM_ISR register (Status Register) is set, the interrupt is not
asserted and the flag in the LPTIM_ISR register is reset.
Interrupt event
Compare match
Auto-reload match
External trigger event
Auto-reload register
update OK
Compare register
update OK
Direction change
Low-power timer (LPTIM) applied to STM32L4P5xx and STM32L4Q5xx only
Table 307. Effect of low-power modes on the LPTIM
No effect. LPTIM interrupts cause the device to exit Sleep mode.
If the LPTIM is clocked by an oscillator available in Stop mode, LPTIM is functional
and the interrupts cause the device to exit the Stop mode (refer to
implementation).
The LPTIM peripheral is powered down and must be reinitialized after exiting Standby
mode.
Table 308. Interrupt events
Interrupt flag is raised when the content of the Counter register
(LPTIM_CNT) matches the content of the compare register (LPTIM_CMP).
Interrupt flag is raised when the content of the Counter register
(LPTIM_CNT) matches the content of the Auto-reload register
(LPTIM_ARR).
Interrupt flag is raised when an external trigger event is detected
Interrupt flag is raised when the write operation to the LPTIM_ARR register
is complete.
Interrupt flag is raised when the write operation to the LPTIM_CMP register
is complete.
Used in Encoder mode. Two interrupt flags are embedded to signal
direction change:
– UP flag signals up-counting direction change
– DOWN flag signals down-counting direction change.
RM0432 Rev 6
Description
Description
Section 42.3: LPTIM
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