F446RC RTC le' bug minimal!

[Mikas Longbardi]

Posted on November 24, 2017 at 02:59

On F446RC, sysreset does not put bit 19 into default setting of 0, its stuck on 1 if 1 is written previously.

Procedure to set and clear bit:

RTC->CR = (0<<19);   //Clear bit19, 512hz mode

RTC->CR = (1<<19);   //Set bit19, 1hz mode

[waclawek.jan]

Posted on November 24, 2017 at 10:14

This is the correct behaviour, as RCC_CR is in the backup domain - read 6.1.3  Backup domain reset and the RCC_CR description in RCC registers chapter.

JW