How Watch Dog Timer works in STOP mode? STOP mode time is more than 5 min. I want to implement WDT in STOP mode but STOP mode time is more than 5 min and WDT reset time is less than 30 sec.

[VChau]

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[KnarfB]

The RTC can be used for wake up after an arbitrarily long time.

hth

KnarfB

[VChau]

Agree, I'm using RTC to Wake up

My question is

What happen if device Hang up (not work properly) in real time scenario(In real application)? How could I reset if device goes Hang up(halt fault)

[VChau]

Thanks for writing, but currently I'm using RTC for wake up....do some take and go back to sleep....

but some time firmware get hang up or stuck some where, So I want to use WDT but i don't know "how

WDT works in Sleep mode"

[KnarfB]

The IWDG can continue counting while the MCU is in low power modes or it can pause counting then. So you may set your RTC to wake up say every 4 minutes and the IWDG to 5 minutes. The RTC can then reset the IWDG. What kind of errors do you want the WDG to care for while the MCU is in STOP mode?

hth

KnarfB