Nonvolatile storage device, access device and nonvolatile storage system

摘要

A memory controller includes a reading/writing control unit for controlling writing and reading of data to and from a physical block of a nonvolatile memory, a writing mode table for storing one of a first writing mode of protecting data against a power shutdown during writing and a second writing mode of writing data at a higher speed than the first writing mode, and a setting unit for setting the writing mode received from an access device in a writing mode table. The reading/writing control unit performs data writing based on the writing mode that has been set in the writing mode table.

主权项

1. A nonvolatile storage device which is capable of communicating with an access device and performs writing and reading of data based on commands from the access device, comprising:
a nonvolatile memory in which the writing and reading of data are performed based on a physical address corresponding to a logical address and which is capable of multilevel writing; and a memory controller for controlling writing operation and reading operation of the nonvolatile memory, wherein the nonvolatile memory includes a plurality of blocks serving as an erase unit, each of the plurality of blocks includes a plurality of pages serving as a write unit, and each of the plurality of pages belongs to a first cell page or a second cell page, the first cell page and the second cell page sharing a memory cell of the nonvolatile memory, the memory controller includes: a conversion table storing correspondence information of a logical address and a physical address of data stored in the blocks; a control unit for specifying the physical address from the conversion table based on the logical address received from the access device, and controlling the writing and reading of data to and from the blocks of the nonvolatile memory; a writing mode table for storing one of a first writing mode of protecting data against a power shutdown during writing and a second writing mode of writing data at a higher speed than the first writing mode; and a setting unit for setting the first writing mode or the second writing mode received from the access device in the writing mode table, and wherein the control unit performs data writing based on the writing mode that has been set in the writing mode table, wherein, if the first writing mode is set in the writing mode table, the control unit performs single level mode writing only in the pages belonging to the first cell page within the block with the physical address specified from the conversion table, and thereafter performs aggregation processing of copying data of a plurality of blocks with data written therein corresponding to the logical address designated from the access device, to an unused block with no data written therein based on multilevel writing, and if a power shutdown occurs during the aggregation processing, the control unit protects data against the power shutdown by abandoning the data written in the block during the aggregation processing when the power is restored and if the second writing mode is set in the writing mode table, the control unit performs multilevel mode writing to the physical address specified from the conversion table.