M41ST84_REG_MONTH
dt->dt_mon = bcdtobin(bcd[M41ST84_REG_MONTH] & M41ST84_MONTH_MASK);
bcd[M41ST84_REG_MONTH] = bintobcd(dt->dt_mon);
bcd[M41ST84_REG_MONTH] = bintobcd(dt->dt_mon) |
(cur[M41ST84_REG_MONTH] & M41ST84_MONTH_CB_MASK);