def METHOD_NAME(self, slave_id, unsigned=True, memory=None):
    """
    Add a new slave with the given id
    """
    if (slave_id < 0) or (slave_id > 255):
        raise Exception("Invalid slave id %d" % slave_id)
    if slave_id not in self._slaves:
        self._slaves[slave_id] = MBSlave(slave_id, self.dom)
        return self._slaves[slave_id]
    else:
        raise DuplicatedKeyError("Slave %d already exists" % slave_id)