RTC_ALARM_VALID
rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_sec))
rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_min))
rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_hour))
rtc_reg = (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mday))
rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mon + 1))
rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_year - 100))