MONTHS_REG
I2C_WRITE(sc, MONTHS_REG, bintobcd(dt->dt_mon));
dt->dt_mon = bcdtobin(I2C_READ(sc, MONTHS_REG));
months_reg = POWER_READ(sc, MONTHS_REG);
POWER_WRITE(sc, MONTHS_REG, bintobcd(dt->dt_mon));