Issue to use PC13 as output on RTC wakeup timer

[Seth1er]

hello all,

I want to write a code to test the possibility to use PC13 as output to activate a regulator when the micro is in Vbat mode.. I'm using a STM32F476.

in the manual, in Vbat mode, RTC_OUT still available for Alarm ou wakeup output.

so, in cube Mx I configure RTC in wakeup mode Routed to out. it active PC13 Pin.

I also enable NVIC interrupt.

I use a callback with a toogle on another GPIO to try my code, and it work with this IO.

I enter in the callback every 10sec but nothing append on PC13.

it seem that pc13, RTC and HAL lib have issue together.

if anyone can help me on this please.

I also try to use the PC13 as simple GPIO and it doesnt work until I change some RTC register manualy...

[Piranha]

> STM32F476

Start with getting a part number right...

[Seth1er]

hello,

I try to test it on a nucleo L476RG where I remove SB17 to disconnect PC13 from user Button and SB45 to disconnect Vbat from VDD.

This is just for test, the target is for a device home made with a STM32L476RGT.

I need to test before finish the pcb.

[Seth1er]

hello @Piranha​ nothing more about the issue please?

[Imen.D]

Hello @Seth1er​ ,

Check that timestamp and tamper are disabled.

Imen

[Piranha]

Check the errata and this one:

https://community.st.com/s/question/0D53W00001yioGiSAI/errata-pin-pc13-is-not-released-when-rtcout-is-remapped-to-pb2