static int setup_rtc(void)
{
/* turn on power block to enable unlocking */
rcc_periph_clock_enable(RCC_PWR);
pwr_disable_backup_domain_write_protect();
/* reset rtc */
RCC_CSR |= RCC_CSR_RTCRST;
RCC_CSR &= ~RCC_CSR_RTCRST;
/* We want to use the LSE fitted on the discovery board */
rcc_osc_on(RCC_LSE);
rcc_wait_for_osc_ready(RCC_LSE);
/* Select the LSE as rtc clock */
rcc_rtc_select_clock(RCC_CSR_RTCSEL_LSE);
/* ?! Stdperiph examples don't turn this on until _afterwards_ which
* simply doesn't work. It must be on at least to be able to
* configure it */
RCC_CSR |= RCC_CSR_RTCEN;
rtc_unlock();
/* enter init mode */
RTC_ISR |= RTC_ISR_INIT;
while ((RTC_ISR & RTC_ISR_INITF) == 0);
/* set synch prescaler, using defaults for 1Hz out */
uint32_t sync = 255;
uint32_t async = 127;
rtc_set_prescaler(sync, async);
/* load time and date here if desired, and hour format */
/* exit init mode */
RTC_ISR &= ~(RTC_ISR_INIT);
/* and write protect again */
rtc_lock();
/* and finally enable the clock */
RCC_CSR |= RCC_CSR_RTCEN;
/* And wait for synchro.. */
rtc_wait_for_synchro();
return 0;
}
void plc_rtc_init( tm* time )
{
uint32_t tmp=0;
uint32_t year;
uint32_t i;
rcc_periph_clock_enable( RCC_PWR );
pwr_disable_backup_domain_write_protect();
PLC_BKP_RTC_IS_OK = 0;
/* LSE oscillator clock used as the RTC clock */
RCC_BDCR |= 0x00000100;
RCC_BDCR |= RCC_BDCR_LSEON;
rcc_periph_clock_enable( RCC_RTC );
rtc_unlock();
RTC_ISR |= RTC_ISR_INIT;
for(i=0; i<1000000; i++)
{
if( RTC_ISR & RTC_ISR_INITF )
{
break;
}
}
if( !(RTC_ISR & RTC_ISR_INITF) )
{
plc_hw_status |= PLC_HW_ERR_LSE;
RTC_ISR &= ~RTC_ISR_INIT;
pwr_enable_backup_domain_write_protect();
return;
}
rtc_set_prescaler( 0x1FF, 0x3F );
tmp = (unsigned long)(time->tm_sec%10 );
tmp |= ((unsigned long)(time->tm_sec/10 )) << 4;
tmp |= ((unsigned long)(time->tm_min%10 )) << 8;
tmp |= ((unsigned long)(time->tm_min/10 )) << 12;
tmp |= ((unsigned long)(time->tm_hour%10)) << 16;
tmp |= ((unsigned long)(time->tm_hour/10)) << 20;
RTC_TR = tmp;
/* Only 2 digits used!!! *time may be const, so use year var. */
year = time->tm_year % 100;
tmp = (unsigned long)(time->tm_day%10 );
tmp |= ((unsigned long)(time->tm_day/10 )) << 4;
tmp |= ((unsigned long)(time->tm_mon%10 )) << 8;
tmp |= ((unsigned long)(time->tm_mon/10 )) << 12;
tmp |= ((unsigned long)(year%10)) << 16;
tmp |= ((unsigned long)(year/10)) << 20;
RTC_DR = tmp;
/* exit from initialization mode */
RTC_ISR &= ~RTC_ISR_INIT;
PLC_BKP_RTC_IS_OK = 1;
pwr_enable_backup_domain_write_protect();
}
