Memory controller, nonvolatile storage device, nonvolatile storage system, and data writing method

• US 7,702,846 B2
• Filed: 03/09/2006
• Issued: 04/20/2010
• Est. Priority Date: 03/15/2005
• Status: Expired due to Fees

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Iwanari, Syunichi, Goho, Yasushi, Nakamura, Yutaka, Inoue, Manabu, Toyama, Masayuki, Nakanishi, Masahiro, Izumi, Tomoaki, Kato, Yoshihisa, Kasahara, Tetsushi, Tamura, Kazuaki, Matsuno, Kiminori
• Primary Examiner(s): NGUYEN, THAN VINH
• Application Number:
  US11/908,715
• Publication Number:
  US 20090055576A1
• Time in Patent Office: 1,503 Days
• Field of Search: None
• US Class Current: 711/103
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 2212/1016 Performance improvement
• CPC Class Codes: G06F 2212/7203 Temporary buffering, e.g. using volatile buffer or dedicated buffer blocks
• CPC Class Codes: G06F 3/0613 in relation to throughput
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0656 Data buffering arrangements
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

A nonvolatile storage device is provided with a nonvolatile main storage memory whose erase size is larger than a cluster size, and a buffer, i.e. a nonvolatile auxiliary storage memory. At the time of writing data in the memory, the data is temporarily stored in the buffer, then, a plurality of data in the buffer are collectively taken out to be stored in the main storage memory. Data in an original block is saved in a write block in the main storage memory. Thus, the data can be written in the main storage memory at a high speed.

Claims

1. A memory controller for reading data from a nonvolatile main storage memory in which an erase size is larger than a cluster size and writing data given from the outside into the main storage memory, comprising:

a first read-write control part for controlling reading and writing of data to said main storage memory;

a nonvolatile auxiliary storage memory which includes data areas and write completion flags showing whether data is written into said data area, for temporarily storing data before being written in said main storage memory; and

a second read-write control part for collectively reading a plurality of data temporarily stored in said auxiliary storage memory and writing them to said main storage memory through said first read-write control part and for resetting the write completion flag in every writing units where said data is actually written.

2. The memory controller according to claim 1, wherein

said main storage memory outputs a write completion signal indicating that data writing in said main storage memory is completed and a status signal indicating a state of the data writing in said main storage memory, and

said second read-write control part creates a transfer success flag indicating that the data writing from the auxiliary storage memory to the main storage memory is successful based on said write completion signal and status signal and writes new data into said auxiliary storage memory based on the transfer success flag.

3. A nonvolatile storage device which comprises:

a nonvolatile main storage memory having a plurality of erase blocks whose size is larger than a cluster size; and

a memory controller for reading data from said main storage memory and wring data given from the outside into said main storage memory, wherein

said memory controller includes;

a first read-write control part for controlling reading and writing of data to said main storage memory;

a nonvolatile auxiliary storage memory which includes data areas and write completion flags showing whether data is written into said data area, for temporarily storing data before being written in said main storage memory; and

a second read-write control part for collectively reading a plurality of data temporarily stored in said auxiliary storage memory and writing them to said main storage memory through said first read-write control part and for resetting said write completion flag in every writing units where the data is actually written.

4. The nonvolatile storage device according to claim 3, wherein

said main storage memory outputs a write completion signal indicating that data writing in said main storage memory is completed and a status signal indicating a state of the data writing in said main storage memory, and

said second read-write control part creates a transfer success flag indicating that the data writing from the auxiliary storage memory to the main storage memory is successful based on said write completion signal and status signal and writes new data into said auxiliary storage memory based on the transfer success flag.

5. A nonvolatile storage system comprising:

a nonvolatile main storage memory;

a memory controller; and

an access device, wherein

said memory controller reads data stored in said main storage memory and writes data into the main storage memory according to said given logical address, and wherein

said main storage memory includes;

a plurality of erase blocks whose size is larger than a cluster size, and

said memory controller includes;

a first read-write control part for controlling reading and writing of data to said main storage memory;

a nonvolatile auxiliary storage memory which includes data areas and write completion flags showing whether data is written into said data area, for temporarily storing data before being written in said main storage memory; and

a second read-write control part for collectively reading a plurality of data temporarily stored in said auxiliary storage memory and writing them to said main storage memory through said first read-write control part and for resetting the write completion flag in every writing units where said data is actually written.

6. The nonvolatile storage system according to claim 5, wherein

said main storage memory outputs a write completion signal indicating that data writing in said main storage memory is completed and a status signal indicating a state of the data writing in said main storage memory, and

said second read-write control part creates a transfer success flag indicating that the data writing from the auxiliary storage memory to the main storage memory is successful based on said write completion signal and status signal and writes new data into said auxiliary storage memory based on the transfer success flag.