M41ST84_REG_SEC
dt->dt_sec = bcdtobin(bcd[M41ST84_REG_SEC] & M41ST84_SEC_MASK);
bcd[M41ST84_REG_SEC] = bintobcd(dt->dt_sec);
cmdbuf[0] = M41ST84_REG_SEC;
bcd[M41ST84_REG_SEC] = bintobcd(dt->dt_sec) |
(cur[M41ST84_REG_SEC] & M41ST84_SEC_ST);