Figure 345. Wake-Up Event Verified; Fifo Disabled); Figure 346. Wake-Up Event Not Verified - STMicroelectronics STM32WL5 Series Reference Manual

Low-power universal asynchronous receiver transmitter (LPUART)
lpuart_ker_ck
Figure 346
Figure 346. Wake-up event not verified (wake-up event = address match,
lpuart_ker_ck
Note: The above figures are valid when address match or any received frame is used as wake-up
event. In the case the wake-up event is the start bit detection, the LPUART sends the wake-
up event to the MCU at the end of the start bit.
1226/1450
Figure 345. Wake-up event verified (wake-up event = address match,
Idle
RX line
Startup time
OFF
Low-power mode
shows the behavior when the wake-up event is not verified.
Idle
RX line
Startup time
OFF

FIFO disabled)

Address match event WUF ='1'
LPUART sends a wakeup event to the MCU
Rx data 1
ON
FIFO disabled)
Address does not match
Rx data 1
ON
Low-power mode
RM0453 Rev 5
Data reception goes on
Rx data 2
Run mode
Idle
OFF
RM0453
MSv40860V2
MSv40861V2