PCF8563_R_MONTH
dt->dt_mon = bcdtobin(bcd[PCF8563_R_MONTH] & PCF8563_M_MONTH);
if ((bcd[PCF8563_R_MONTH] & PCF8563_M_CENTURY) == 0)
bcd[PCF8563_R_MONTH] = bintobcd(dt->dt_mon);
bcd[PCF8563_R_MONTH] |= PCF8563_M_CENTURY;