Method and data storage device for writing a minimum number of memory cells in a memory device

• US 6,651,133 B2
• Filed: 09/23/2002
• Issued: 11/18/2003
• Est. Priority Date: 09/15/2000
• Status: Expired due to Fees

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: Matrix Semiconductor, Inc. (Western Digital Corporation)
• Inventors: Moore, Christopher S., Brown, Daniel T., March, Roger W.
• Primary Examiner(s): PORTKA, GARY J
• Application Number:
  US10/253,218
• Publication Number:
  US 20030028717A1
• Time in Patent Office: 421 Days
• Field of Search: 711/102, 711/103, 711/172, 711/171, 707/100, 707/101, 707/1, 707/4
• US Class Current: 711/102
• CPC Class Codes: G06F 11/1008 in individual solid state devices G06F11/1004 takes precedence
• CPC Class Codes: G06F 2003/0697 device management, e.g. handlers, drivers, I/O schedulers
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: G06F 3/08 from or to individual record carriers, e.g. punched card , memory card, integrated circuit [IC] card or smart card
• CPC Class Codes: G11C 17/00 Read-only memories programmable only once; Semi-permanent stores, e.g. manually-replaceable information cards
• CPC Class Codes: Y10S 707/99934 Query formulation, input preparation, or translation
• CPC Class Codes: Y10S 707/99943 Generating database or data structure, e.g. via user interface
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99956 File allocation

Abstract

The preferred embodiments described herein provide a memory device and methods for use therewith. In one preferred embodiment, a method is presented for using a file system to dynamically respond to variability in an indicated minimum number of memory cells of first and second write-once memory devices. In another preferred embodiment, a method for overwriting data in a memory device is described in which an error code is disregarded after a destructive pattern is written. In yet another preferred embodiment, a method is presented in which, after a block of memory has been allocated for a file to be stored in a memory device, available lines in that block are determined. Another preferred embodiment relates to reserving at least one memory cell in a memory device for file structures or file system structures. A memory device is also provided in which file system structures of at least two file systems are stored in the same memory partition. Additionally, methods for permanently preventing modification of data stored in a memory device and for identifying memory cells storing data are disclosed.

Claims

1. A method for storing data in first and second write-once memory devices, the method comprising:

(a) sending, from a first write-once memory device to a file system, an indication of a minimum number of memory cells of the first write-once device that can be written into during a write operation;

(b) writing data into no less than the indicated minimum number of memory cells of the first write-once memory device;

(c) sending, from a second write-once memory device to the file system, an indication of a minimum number of memory cells of the second write-once memory device that can be written into during a write operation; and

(d) writing data into no less than the indicated minimum number of memory cells of the second write-once memory device;

wherein the file system is informed of the minimum numbers of memory cells that can be written into the memory devices during a write operation by the indications received from the memory devices and not by a driver installed on a data storage device.

2. The method of claim 1, wherein the indication in at least one of (a) and (c) is sent in response to a read command sent from the file system.

3. The method of claim 1, wherein the indication in at least one of (a) and (c) is sent in response to a reset command sent from the file system.

4. The method of claim 1, wherein the indication in at least one of (a) and (c) is automatically sent to the file system.

5. The method of claim 1, wherein the indication of at least one of the first and second write-once memory devices is written during a format operation.

6. The method of claim 1, wherein the indication of at least one of the first and second write-once memory devices is pre-written by a manufacturer of the device.

7. The method of claim 1, wherein at least one of the first and second write-once memory devices is logically organized into a plurality of lines, and wherein a line comprises the minimum number of memory cells.

8. The method of claim 1, wherein at least one of the first and second write-once memory devices comprises a three-dimensional write-once memory device.

9. A data storage device comprising:

a file system operative to;

receive an indication from a memory device coupled with the data storage device concerning a minimum number of memory cells that can be written into the memory device during a write operation, wherein the file system is informed of the minimum number of memory cells that can be written into the memory device during a write operation by the indication received from the memory device and not by a driver installed on the data storage device;

writing the minimum number of memory cells indicated by the memory device to the memory device;

wherein the file system is operative to dynamically respond to variability in different indications of minimum number of memory cells from different memory devices without using drivers associated with each of the different memory devices.

10. The data storage device of claim 9, wherein the indication concerning the minimum number of memory cells is received from a write-once memory device.

11. The data storage device of claim 9, wherein the indication concerning the minimum number of memory cells is received from a three-dimensional memory device.

12. A data storage device comprising:

a file system;

a driver operative to facilitate communication between the file system and a first memory device coupled with the data storage device, wherein the data storage device does not comprise a driver operative to facilitate communication between the file system and a second memory device, the first and second memory devices having different minimum numbers of memory cells that can be written into during a write operation;

wherein the file system is operative to receive an indication from the second memory device concerning a minimum number of memory cells that can be written to the second memory device during a write operation and, without using a driver to facilitate communication between the file system and the second memory device, writing the minimum number of memory cells indicated by the second memory device to the second memory device;

wherein the second memory device can be used with the data storage device even though the data storage device does not comprise a driver to facilitate communication between the file system and the second memory device.

13. The data storage device of claim 12, wherein at least one of the first and second memory devices comprises a write-once memory device.

14. The data storage device of claim 12, wherein at least one of the first and second memory devices comprises a three-dimensional memory device.