RTC_START
rtc_write(RTC_CONTROL, rtc_read(RTC_CONTROL) & ~RTC_START);
rtc_write(RTC_CONTROL, rtc_read(RTC_CONTROL) | RTC_START);
rtc_write(RTC_CONTROL, rtc_read(RTC_CONTROL) & ~RTC_START);
rtc_write(RTC_CONTROL, rtc_read(RTC_CONTROL) | RTC_START);