Patent ID: 6795890
Filing Date: 2004-09-21
Classification: G11C

Abstract:
A data storage method by which data stored in memory are rewritten through use of memory having a plurality of erasure-unit regions into which data are written in predetermined units and from which data are erased in predetermined units, as well as a nonvolatile erasure block buffer for storing write data that is to be written into the erasure-unit regions and non-changing data belonging to the erasure-unit regions,said method comprising: a first erasure block buffer write step of writing first write data into said erasure block buffer, in response to a first write request for requesting writing of the first write data into a first erasure-unit region of said memory; a second erasure block buffer write step of writing into said erasure block buffer non-changing data recorded in the first erasure-unit region, in response to the first write request for requesting writing of the first write data into the first erasure-unit region of said memory; a third erasure block buffer write step of writing second write data into said memory, in response to a second write request for requesting writing of the second write data into said memory, after the first erasure block buffer write step; and a memory write step of writing the first write data and the non-changing data written in said erasure block buffer into the first erasure-unit region after the second erasure block buffer write step and the third erasure block buffer write step.