Nonvolatile semiconductor memory device with write protect data settings for disabling erase from and write into a block, and erase and re-erase settings for enabling write into and erase from a block

摘要

A nonvolatile semiconductor memory device including: a memory cell array for storing data therein in a nonvolatile manner; block protect data storage regions provided for the respective blocks, for storing data therein in a nonvolatile manner; and block protect means for disabling an erase and a write of data from/into a block, if block protect data has been stored in the block protect data storage region of the block and a write protect signal has been activated. The device is characterized by: erase complete data storage regions, provided for the respective blocks, for storing data therein in a nonvolatile manner; erase complete data set means for writing erase complete data into the erase complete data storage region of a block after an erase of data from the block has been completed; and re-erase enable means for enabling an erase of data from a block if the erase complete data has not been stored in the erase complete data storage region of the block, irrespective of a function of the block protect means.