RTCSB_24HR
writertc(RTC_STATUSB, RTCSB_HALT | RTCSB_24HR);
rtc_statusb = RTCSB_24HR;
static u_char rtc_statusb = RTCSB_24HR | RTCSB_PINTR;
writertc(RTC_STATUSB, RTCSB_24HR);
writertc(RTC_STATUSB, RTCSB_24HR);
writertc(RTC_STATUSB, RTCSB_24HR);