A method and apparatus for assigning a device identifier for a plurality of devices of mixed type (e.g., DRAMs, SRAMs, MRAMs, and NAND-, NOR- and AND-type Flash memories) in a serial interconnection configuration are disclosed. One device of the serial interconnection configuration receives a device identifier (ID) and a device type (DT) as a packet through its serial input connection. A first determination is performed as to whether the DT of the device contains pre-defined data corresponding to one including all device types to provide a first determination result; and a second determination of the DT of the device is performed in response to the received DT to provide a second determination result. An ID is produced and output to a next device in response to the first and second determination results. The received ID or the produced ID is assigned to the respective devices.