purpose of RCC_RSR_RMVF

[mete]

I read RCC RSR to determine the cause of reset. It is not clear to me the purpose of RMVF bit. I guess it resets the other flags but why would I want that ? I wonder if I am missing something.

[STTwo-32]

Hello @mete 

Thank you for reporting this. I will check it internally and get back to you as soon as possible.

Best Regards.

STTwo-32

[STTwo-32]

Hi @mete  

The RMVF bit of the RCC_RSR is Set and reset by software to reset the value of the reset flags since those flags are read only so we need to reset them using an external source (wish is the RMVF in this case). 

For the Typo in the RM0481 Rev 1 (the RCC reset status register (RCC_RSR) bits [26,31] should be read only (r) not read/write (rw). I've escalated this to the appropriate team for correction of UM3115 with internal ticket ID166678.

(PS: ID166678 is an internal tracking number and is not accessible or usable by customers)

thank you for your contribution.

Best Regards.

STTwo-32.

[mete]

Thanks @STTwo-32 , what I do not understand is why I would want to reset the status of reset flags. Do they not always reflect the reset status after a reset happens ? For what reason would I need to reset it manually using RMVF ?

[STTwo-32 · Accepted solution]

After a reset happens, the reset flag will be set and will keep set until we clear it using the RMVF bit. If we don't, we will not be able to detect the next reset coming from the same source (because the flag will keep set and we will never now if it is the first reset or  an other one). 

Best Regards.

STTwo-32

[mete]

Thanks @STTwo-32 , OK I see, I thought all of them are automatically zero after reset. So basically I have to read the flags then reset them with RMVF after every boot since I am interested in reading the reset reason after every boot. Thanks again.