Patent ID: 8307172

Claim:
A memory system comprising: a nonvolatile memory corresponding to a memory space which consists of a group of logical addresses, the memory space being formatted from outside by an additional-write type file system; and a memory controller controlling the nonvolatile memory, wherein the memory controller is configured to (1) receive, from the outside, a first logical address and a request for writing to the first logical address; (2) determine whether the received first logical address is equal to or smaller than a second logical address associated with the first data which has been written in the nonvolatile memory; (3) output an error to the outside when the received first logical address is equal to or smaller than the second logical address; and (4) convert the first logical address into a physical address, and write second data to the nonvolatile memory using the physical address, when the received first logical address is larger than the second address, and wherein the first and second logical addresses belong to the group of the logical addresses.