MEMORY SYSTEM
According to the embodiments, a memory system includes a nonvolatile semiconductor memory and a writing-loop-count monitoring unit that monitors a loop count of an applied voltage to the nonvolatile semiconductor memory required for data writing of the nonvolatile semiconductor memory as a writing loop count. Moreover, the memory system includes a management table for managing the writing loop count in block unit that is a unit of data erasing and a life managing unit that determines a degraded state of the nonvolatile semiconductor memory based on the management table.
1 . (canceled)
2 . A system comprising:
a memory system; and
a management unit to be installed in a host with a display device to be connected to the memory system,
the memory system comprising:
a semiconductor nonvolatile memory which includes a plurality of blocks as a unit of data erasing;
a nonvolatile random access memory; and
a controller configured to control the semiconductor nonvolatile memory and the nonvolatile random access memory, wherein
the nonvolatile random access memory is configured to store a first information related to a degraded state of the semiconductor nonvolatile memory, and
the management unit is configured to cause the display device to display a warning based upon the first information.
3 . The system according to claim 2 , wherein
the management unit is configured to cause the display device to display a first warning based upon the first information, and when degradation has progressed, configured to cause the display device to further display a second warning that indicates a life of the memory system becomes shorter based upon the first information.
4 . The system according to claim 2 , wherein
the management unit is configured to determine which degraded stage the degraded state is among a plurality of degraded stages, and cause the display device to display a third warning that indicates the determined degraded stage.
5 . The system according to claim 3 , wherein
the semiconductor nonvolatile memory is a NAND flash memory.
6 . The system according to claim 5 , wherein
the first information is managed in block units in the semiconductor nonvolatile memory.
7 . The system according to claim 6 , wherein
the first information includes a loop count at a time of erasing in the semiconductor nonvolatile memory for each block unit.
8 . The system according to claim 6 , wherein
the first information includes a loop count at a time of writing in the semiconductor nonvolatile memory for each block unit.
9 . The system according to claim 6 , wherein
the nonvolatile random access memory is a FeRAM.
10 . The system according to claim 6 , wherein
the nonvolatile random access memory is a MRAM.
11 . A method of managing a memory system which is connected to a host with a display device and includes a semiconductor nonvolatile memory and a nonvolatile random access memory, the semiconductor nonvolatile memory including a plurality of blocks as a unit of data erasing, the method comprising:
controlling the semiconductor nonvolatile memory and the nonvolatile random access memory;
storing a first information related to a degraded state of the semiconductor nonvolatile memory, in the s nonvolatile random access memory; and
displaying a warning based upon the first information.
12 . The method according to claim 11 , further comprising:
displaying a first warning based upon the first information, and when degradation has progressed, further displaying a second warning that indicates a life of the memory system becomes shorter based upon the first information.
13 . The method according to claim 11 , further comprising:
determining which degraded stage the degraded state is among a plurality of degraded stages, and
displaying a third warning that indicates the determined degraded stage.
14 . The method according to claim 12 , wherein
the semiconductor nonvolatile memory is a NAND flash memory.
15 . The method according to claim 14 , further comprising:
managing the first information in block units in the semiconductor nonvolatile memory,
16 . The method according to claim 15 , wherein
the first information includes a loop count at a time of erasing in the semiconductor nonvolatile memory for each block unit.
17 . The method according to claim 15 , wherein
the first information includes a loop count at a time of writing in the semiconductor nonvolatile memory for each block unit.
18 . The method according to claim 15 , wherein
the nonvolatile random access memory is a FeRAM.
19 . The method according to claim 15 , wherein
the nonvolatile random access memory is a MRAM.