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What is RTC_CR.WUTIE for (STM32L476)?

Question asked by kleier.hermann on Mar 21, 2017
Latest reply on Sep 27, 2017 by Imen D

I require a periodic wakeup from shutdown-mode. For that I found two recipes: AN4759 (table 7) and RM0351 (section 34.3.7). Essentially they provide the same info. Unfortunately it did not work until I tripped over “When the periodic wakeup interrupt is enabled by setting the WUTIE bit in the RTC_CR2 register, it can exit the device from low-power modes.” (RM0351, section 34.3.6)

I added “LL_RTC_EnableIT_WUT (RTC);” and it worked as expected.

I was puzzled because the NVIC is powered off in shutdown mode. So there are no interrupts.

Isn’t there something missing in the recipes? Is WUTIE really required?

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