/* Enables or disables access to the RTC and backup registers.  */
void PWR_BackupAccessCmd(FunctionalState state)
/* Enables or disables access to the RTC and backup registers.  */
void PWR_BackupAccessCmd(FunctionalState state)
{
    (state) ? (RCC->BDCR |= RCC_BDCR_DBP) : (RCC->BDCR &= ~RCC_BDCR_DBP);
}