EM3027_WATCH_BASE
if (reg == EM3027_WATCH_BASE)
error = em3027rtc_read(sc, EM3027_WATCH_BASE, &w, sizeof(w));
error = em3027rtc_write(sc, EM3027_WATCH_BASE, &w, sizeof(w));
#define EM3027_WATCH_SIZE (EM3027_WATCH_YEAR - EM3027_WATCH_BASE + 1)