APPARATUS AND METHOD FOR PRODUCING IDENTIFIERS REGARDLESS OF MIXED DEVICE TYPE IN A SERIAL INTERCONNECTION

摘要

A plurality of memory devices of mixed type (e.g., DRAMs, SRAMs, MRAMs, and NAND-, NOR- and AND-type Flash memories) is serially interconnected. Each device has device type information on its device type. A specific device type (DT) and a device identifier (ID) contained in a serial input (SI) as a packet are fed to one device of the serial interconnection. The device determines whether the fed DT matches the DT of the device. In a case of match, a calculator included in the device performs calculation to generate an ID accompanying the fed DT for another device and the fed ID is latched in a register of the device. In a case of no match, the ID generation is skipped and no ID is generated for another device. The DT is combined with the generated or the received ID depending on the device type match determination. The combined DT and ID is as a packet transferred to a next device. Such a device type match determination and ID generation or skip are performed in all devices of the serial interconnection. With reference to device type provided to the interconnected devices, IDs are sequentially generated. The SI containing the DT, the ID and an ID generation command is transmitted in a packet basis to a next device. A memory controller can recognize the total number of one DT, in response to the ID received from the last device. In a case of a "don't care" DT is provided to the interconnected devices, IDs are sequentially generated and the total number of the interconnected devices is recognized, regardless of the differences in DTs of the devices.