Patent ID: 7272057

Claim:
A memory apparatus comprising: main memory means; redundant memory means for relieving a defect existing in the main memory means; identification number storing means for storing an identification number corresponding to a main memory cell; relief command input means to which a relief command including an identification number is inputted; memory space severing means for severing a memory space corresponding to a defect existing in the main memory means from the main memory means so as to render the memory space inoperative; and allocating means for allowing allocation of the redundant memory means so as for a defective memory space of the main memory means to be replaced with a memory space of the redundant memory means, wherein the allocating means is operated in such a manner that, when an identification number included in a relief command coincides with an identification number stored in the identification number storing means, a memory space corresponding to a defect existing in the main memory means specified by the relief command inputted to the relief command input means is severed from the main memory means so as to be rendered inoperative, when an identification number included in a relief command coincides with an identification number stored in the identification number storing means, a memory space corresponding to a defect existing in the main memory means specified by the relief command inputted to the relief command input means is replaced with a memory space of the redundant memory means, and when an identification number included in a relief command does not coincide with an identification number stored in the identification number storing means, a memory space corresponding to a defect existing in the main memory means of another memory apparatus specified by the relief command inputted to the relief command input means is replaced with a memory space of the redundant memory means of the memory apparatus of interest.