File managing device of a non-volatile memory, a memory card and method for controlling a file system

• US 5,860,135 A
• Filed: 01/17/1996
• Issued: 01/12/1999
• Est. Priority Date: 01/18/1995
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Sugita, Masahiro
• Primary Examiner(s): Chan, Eddie P.
• Assistant Examiner(s): NGUYEN, THAN VINH
• Application Number:
  US08/587,492
• Time in Patent Office: 1,091 Days
• Field of Search: 395/621, 395/622, 395/652, 395/430, 365/185.11, 365/185.29, 365/185.33, 411/4, 411/5, 411/115, 411/202, 411/170, 411/173
• US Class Current: 711/173
• CPC Class Codes: G06F 16/9017 using directory or table look-up use of a directory or look-up table in file systems G06F16/13
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0616 in relation to life time, e.g. increasing Mean Time Between Failures [MTBF]
• 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 9/4406 Loading of operating system

Abstract

The present invention sets a first boot record indicating a first file group information on a head address of a non-volatile memory a second boot record indicating a second file group information on an end address of the non-volatile memory without partitioning the non-volatile memory. When accessing to files of first file group, an address is generated based on information on the first boot record. When accessing to files of second file group, an address is generated based on information on the second boot record.

Claims

1. A file managing device for a non-partitioned non-volatile memory, said file managing device comprising:

a first boot record storing means for storing a first boot record indicating information of a first file group at a head address of said non-partitioned non-volatile memory; and

a second boot record storing means for storing a second boot record indicating information of a second file group at an end address of said non-partitioned non-volatile memory.

2. The file managing device of claim 1, further comprising:

first address generation means for generating an address for accessing a file of said first file group based on information contained in said first boot record; and

second address generation means for generating an address for accessing a file of said second file group based on information contained in said second boot record.

3. The file managing device of claim 1, further comprising:

means for establishing a block allocation structure area in said non-volatile memory, where said block allocation structure area stores erasing frequency information of each block of said non-volatile memory and information on usable data areas.

4. The file managing device of claim 3, wherein said means for establishing a block allocation structure area identifies an occupied area whether said occupied area is occupied by said first file group or said second file group and stores said occupied area into said block allocation structure area.

5. The file managing device of claim 3, wherein said means for establishing a block allocation structure area establishes two of said block allocation structure areas on said non-volatile memory.

6. The file managing device of claim 1, further comprising writing means for writing data into said non-volatile memory in a unit of 1 byte.

7. The file managing device of claim 1, further comprising erasing means for erasing information within a block of said non-volatile memory in a unit of 64k byte.

8. A file managing device of a non-partitioned non-volatile memory, a memory card and method for controlling a file system, said file managing device comprising:

means for storing a first boot record indicating information of a first file group at a head address on said non-volatile memory without partitioning said non-volatile memory;

means for storing a second boot record indicating information of a second file group, at an end address on said non-volatile memory without partitioning said non-volatile memory;

first address generation means for generating an address for accessing to files of said first file group based on said information of said first boot record;

second address generation means for generating an address for accessing files of said second file group based on said information of said second boot record; and

means for allocating two of block allocation structure areas on said non-volatile memory, wherein each of said block allocation structure area stores block erasing frequency information of each block, information on areas not used for said first file group, information on areas not used for said second file group, and information on usable areas.

9. A non-partitioned, non-volatile memory comprising:

a plurality of memory cells including a head plurality of memory cells located at head address of said memory and an end plurality of memory cells located at an end address of said memory;

a first boot record contained in said head plurality of memory cells, said first boot record indicating information related to a first file group; and

a second boot record contained in said end plurality of memory cells, said second boot record indicating information related to a second file group, wherein each of said first and second file groups can be stored anywhere throughout said plurality of memory cells.

10. The memory of claim 9, wherein said non-partitioned non-volatile memory includes a block allocation structure area storing erasing frequency information of each block and information of usable data areas.

11. The memory of claim 10, wherein said block allocation structure area stores an occupied area after identifying an occupied area whether said occupied area is occupied by said first file group or said second file group.

12. The memory of claim 10, wherein two of said block allocation structure area are allocated on said non-partitioned non-volatile memory.

13. The memory of claim 9, further comprising a connector on said non-partitioned non-volatile memory for connecting said non-volatile memory with a read and write device.

14. The memory of claim 9, wherein said non-partitioned non-volatile memory is a flash memory.

15. A method for controlling a file system of a non-partitioned non-volatile memory, comprising steps of:

a first boot record indicating information of storing a first file group at a head address of said non-volatile memory;

storing second boot record indicating information of a second file group at an end address of said non-volatile memory; and

generating an address for accessing a file of said first file group based on information of said first boot record when reading or writing files of said first file group, and generating an address for accessing a file of said second file group based on said information of second boot record when reading or writing files of said second file group.

16. The method for controlling a file system of a non-partitioned non-volatile memory of claim 15, further comprising a step of allocating a block allocation structure area on said non-partitioned non-volatile memory, wherein said block allocation structure area stores erasing frequency information of each block of said non-partitioned non-volatile memory and information on usable data areas.

17. The method for controlling a file system of a non-partitioned non-volatile memory of claim 16, wherein said step of allocating a block allocation structure area identifies an occupied area whether said occupied area is occupied by said first file group or said second file group and stores said occupied area into said block allocation structure area.

18. The method for controlling a file system of a non-partitioned non-volatile memory of claim 15, wherein said steps of storing said first boot record and said second boot record do not need to partition said non-partitioned non-volatile memory for storing said first boot record and said second boot record.