BKP0R clear after a Tamper event

[Marco1]

Posted on May 08, 2018 at 17:13

Hi,

i'm working with stm32f415RG and i have a strange behaviuor with RTC.

I configured RTC with LSE

Alarm A Internal Alarm

Alarm B Internal Alarm

WakeUp : internal wakeup

Tamper1 Routed to AF1

TimeStamp on Tamper detection event is not saved

After init of RTC, BKP0R register is setted with 0x32F2 value, but immediatly after a tamper event, this value return to 0x00000. 

Its normal ?

Sorry for my english

[Marco1]

Posted on May 08, 2018 at 17:25

Solved,i found the answer:

RTC_BKPxR, where x=0 to n backup registers (80 bytes), are reset when a tamper

detection event occurs. These registers are powered-on by VBAT when VDD is switched off,so that they are not reset by a system reset, and their contents remain valid when the deviceoperates in low-power mode.