Non-volatile data storage system and data storaging method
View Patent ↗This invention realizes separate control for each memory area. A memory unit is structured by including a semiconductor memory device capable of memorizing information, the aforementioned memory device is divided into plural memory areas logically and also management table, which is capable of controlling separately each aforementioned memory area for accessing from the outside, is tabled, control information, which prohibits accessing the prescribed memory area of the aforementioned plural memory areas, is provided in the aforementioned management information, and it is prohibited to access the specified memory area from the outside in accordance with control information.
1. A nonvolatile memory device comprising:
a nonvolatile memory array; and
a control unit,
wherein said nonvolatile memory array comprises a user data storing area and a management data storing area,
wherein said user data storing area comprises a plurality of data blocks,
wherein said management data storing area stores management information which includes a first flag,
wherein a multiple data storing function is enabled when said first flag is in a first state, and said multiple data storing function is not enabled when said first flag is in a second state,
wherein said control unit controls an arbitrary one of operations in accordance with a command received from outside,
wherein a write operation of said operations in accordance with a write command accompanies program data for storing to a first data block of said data blocks, said control unit selects said first data block, fetches management information corresponding to said first data block, checks whether said first flag is in said first state or not, stores said program data to said first data block, and stores said program data to a second data block different from said first data block when said first flag is in said first state.
2. A nonvolatile memory device according to claim 1 ,
wherein said management information has a plurality of entries,
wherein each of said entries has said first flag in accordance with each of said data blocks, respectively, and
wherein said first flag is in a first entry in accordance with said first data block.
3. A nonvolatile memory device according to claim 2 ,
wherein said write operation in accordance with said write command accompanies a second program data for storing to a third data block, said control unit selects said third data block, fetches a second entry in accordance with said third data block, checks whether said first flag in said second entry is in said first state or not, stores said second program data to said third data block, and does not store said second program data to any other data blocks when said first flag in said second entry is in said second state.
4. A nonvolatile memory device according to claim 3 ,
wherein each of said entries further has a second flag,
wherein a data write inhibiting function is enabled when said second flag is in said first state, and said data write inhibiting function is not enabled when said second flag is in said second state, and
wherein said write operation in accordance with said write command accompanies third program data for storing to a fourth data block, fetches a third entry in accordance with said fourth data block, checks whether said second flag in said third entry is in said first state or not, and inhibits storing said third program data to said fourth data block when said second flag in said third entry is in said first state.
5. A nonvolatile memory device according to claim 4 ,
wherein both of said second flag in said first entry and said second flag in said second entry are in said second state.
6. A nonvolatile memory device according to claim 5 ,
wherein each of said entries further has a third flag, wherein a data read inhabiting function is enabled when said third flag is in said first state, and said data read inhibiting function is not enabled when said third flag is in said second state, and
wherein said third flag in said first entry is capable of being in said first state.
7. A nonvolatile memory device according to claim 6 ,
wherein said read operation of said operations in accordance with a read command for reading data from said first data block, said control unit selects said first data block, fetches said first entry, checks whether said third flag in said first entry is in said first state or not, and
inhibits reading said first program data from said first data block when said third flag in said first entry is in said first state, or
reading said first program data from said first data block when said third flag in said first entry is in said second state.
8. A nonvolatile memory device according to claim 7 ,
wherein said read operation for reading data from said third data block, said control unit selects said third data block, fetches said second entry, checks whether said third flag in said second entry is in said first state or not, and inhibits reading said second program data from said third data block when said third flag in said second entry is in said first state.
9. A nonvolatile memory device according to claim 8 ,
wherein said read operation for reading data from said fourth data block, said control unit selects said fourth data block, fetches said third entry, checks whether said third flag in said third entry is in said first state or not, and reads stored data from said fourth data block when said third flag in said third entry is in said second state.