JP2001084180A - File managing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a file managing device normally resuming a file operation without destroying any file or data even when an abnormal state such as power source interruption is generated during the file operation. SOLUTION: In this file managing device, an identification code indicating the processing contents of wiring processing or the like are recorded in an operation history recording region 10, and when the writing processing or the like is normally ended, the identification code is deleted. Afterwards, when the recording of the identification code is left in the operation history recording region 10, the identification code is analyzed, and the data stored in the data region or the like are restored.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file management apparatus for accessing a flash memory capable of erasing data in block units.

[0002]

2. Description of the Related Art In recent years, flash memories are widely used as storage media for portable information devices such as digital still cameras and PDAs. A flash memory is an electrically readable and writable non-volatile memory, such as an SRAM or a DRAM.
Unlike a RAM, it has a feature that data can be retained even after power is turned off.

However, a flash memory cannot be overwritten, and in order to rewrite data at an arbitrary address in a physical address space, it is necessary to temporarily erase the data. A flash memory is usually composed of a plurality of blocks, and data can be erased only in block units. The size of the block varies from chip to chip, but is from a few kilobytes to a few hundred kilobytes.

FIG. 19 is an explanatory diagram showing a logical format on a flash memory in a conventional file management apparatus disclosed in Japanese Patent Application Laid-Open No. 11-53248, for example.
In the figure, 100 is a reserved area, 101 is a FAT (Fi
le AllocationTable), 102 is a directory area, 103 is a data area, and 104 is an arbitrary area in the data area 103.

As shown in FIG. 19, the storage area of the flash memory is divided into a reserved area 100, a FAT 101, a directory area 102, and a data area 103, and the data area is composed of a plurality of blocks. FA
The technique of managing files with T and a directory is a well-known technique that has been well known in the art, and a brief description will be given below.

The data area 103 is an area for storing file data, and is logically divided into fixed-size areas called sectors. The data area 103 is accessed in units of sectors (those handling large-capacity storage areas are accessed in units called clusters composed of a plurality of consecutive sectors).
It is a value such as 56 bytes or 512 bytes.

[0007] A file is stored in a plurality of sectors according to its data size. Even if the file size is not divisible by the sector size, the last sector is occupied by the file, and the data of another file is not stored in the surplus area of the sector. The FAT 101 has an entry corresponding to each sector on a one-to-one basis, and it can be known from the FAT 101 entry whether data is written to the sector or whether the sector is a free sector.

In the directory area 102, a file name, a file size, file attribute information, a file start sector number, and the like are recorded. Also, FAT10
1 includes map information indicating in which sector the file data is stored in which order.

If the file cannot be stored in one sector, the FAT 101 entry records the number of the sector in which data is to be stored continuously. When reading the file data, the FAT entries are sequentially read from the starting sector number recorded in the directory, so that the file data separately recorded in a plurality of sectors can be read as one data.

Next, the conventional file management device is
The operation when updating the file recorded in No. 4 will be described. FIG. 20 is a flowchart showing the processing contents of a conventional file management device. First, the file management device searches for a free block in the data area 103 (step ST201).

Next, the file management apparatus copies files recorded in an area other than the area 104 among the files recorded in the block (5) where the area 104 exists, to an empty block (step ST20).
2) Copy the updated file recorded in the area 104 to the empty block (step ST203).

When the file management device completes copying the file, it deletes block (5) (step ST204), and deletes the FAT 101 and the directory area 1.
02 is updated (step ST205).

[0013]

Since the conventional file management apparatus is configured as described above, when the flash memory is mounted on a portable information device or the like, the following problems occur. That is, since a portable information device uses a battery (battery) as a main power supply, the power supply may be suddenly shut down due to the exhaustion of the battery (or the power supply may be shut down due to a user's erroneous operation). .
For example, when the power supply shuts down after the execution of step ST204 in FIG. 20, the FAT 101 and the directory area 102 are deleted even though the block (5) is erased.
Because the data of has not been updated, restart the power supply,
There is a problem in that if an attempt is made to read the corresponding file after updating, the file in the erased state (the file of block (5)) is read.

[0014] The block in which the updated file is recorded also has an FA regardless of the recorded file.
Since the entry in T101 is recognized as an empty sector area, there is a problem that a file cannot be written correctly. Further, when updating the FAT101, the FAT101
If the power is cut off when the file is erased, the data in the FAT 101 is completely lost, and all the files cannot be read.

[0015] The present invention has been made to solve the above-described problem, and even if an abnormal state such as a power shutdown occurs during a file operation, the file operation can be performed without destroying the file or data. An object of the present invention is to provide a file management device that can be restarted normally.

[0016]

A file management device according to the present invention records an identification code indicating the processing content in an operation history recording area of a flash memory when a writing means executes a writing process or an updating process. When the writing process or the updating process is completed normally, an operation history recording means for erasing the identification code is provided, and when the identification code is recorded in the operation history recording area of the flash memory, the identification code is deleted. Is analyzed to recover the data stored in the data area and the management area.

In the file management device according to the present invention, when the writing means executes a writing process or an updating process, an identification code indicating the processing content is recorded in an operation history recording area of the flash memory, and the writing process is performed. Or, when the update processing is normally completed, an operation history recording unit that records an identification code indicating a normal end in the operation history recording area is provided, and an identification code indicating a normal end is not recorded in the operation history recording area of the flash memory. An analysis of the identification code indicating the contents of the processing is performed to recover the data stored in the data area and the management area.

The file management apparatus according to the present invention executes a recovery process according to the analysis result of the identification code, and writes or updates the data stored in the data area and the management area before the execution of the update processing. The content is returned.

In the file management apparatus according to the present invention, when the deletion means executes the deletion processing or the update processing, the identification code indicating the processing content is recorded in the operation history recording area of the flash memory, and the deletion processing or the update processing is performed. Is normally completed, an operation history recording means for erasing the identification code is provided. If the identification code is recorded in the operation history recording area of the flash memory, the identification code is analyzed and the data area and the data area are analyzed. The data stored in the management area is restored.

In the file management device according to the present invention, when the deletion means executes the deletion processing or the update processing, the identification code indicating the processing content is recorded in the operation history recording area of the flash memory, and the deletion processing or the update processing is performed. Is normally provided, an operation history recording means for recording an identification code indicating the normal end in the operation history recording area is provided. If the identification code indicating the normal end is not recorded in the operation history recording area of the flash memory, the processing is performed. The identification code indicating the content is analyzed to restore the data stored in the data area and the management area.

The file management apparatus according to the present invention executes recovery processing according to the analysis result of the identification code, and deletes data stored in the data area and the management area before the deletion processing or the update processing is performed. It is intended to return to the contents.

According to the file management apparatus of the present invention, only when the same identification code is recorded twice consecutively,
The identification code is handled as a valid identification code.

In the file management apparatus according to the present invention, when the detecting means detects a hardware error, the processing of the writing means is stopped and the processing of the restoring means is started.

In the file management apparatus according to the present invention, when the detecting means detects a hardware error, the processing of the deleting means is stopped and the processing of the restoring means is started.

The file management device according to the present invention executes the same processing as when the detecting means detects a hardware error when the detecting means cannot receive a hardware error status signal from the flash memory for a certain period of time or more. It is like that.

In the file management apparatus according to the present invention, when the writing means is writing file data to one bank, a reading means for reading data from the other bank is provided.

The file management apparatus according to the present invention is provided with reading means for reading data from the other bank when the deleting means is deleting a sector from one bank.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a block diagram showing a file management device according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an external input via an I / F unit 4 in response to an input signal from a key input unit 3. Flash memory 5
The I / F unit 4 reads the file stored in the flash memory 5 and outputs the data to the outside, or transfers the file data stored in the flash memory 5 to the VRAM 6. This is an MPU for displaying on the display unit 7 or deleting a file stored in the flash memory 5.

Reference numeral 2 denotes a ROM for storing a program executed by the MPU 1 and the like. Reference numeral 3 denotes a key input unit provided with a switch for turning on and off a power supply and various keys for receiving various operations from a user. ,
An I / F unit for outputting data to the outside, 5 a flash memory capable of erasing data in block units, 6 a VRAM for storing data and the like, 7 a display unit for displaying data and the like, and 8 a display unit for displaying data and the like A RAM used as a work memory when the MPU 1 executes various processes. Note that MP
U1 constitutes a writing unit, a deleting unit, an operation history recording unit, and a recovery unit.

FIG. 2 is an explanatory diagram showing a logical format on the flash memory 5 in the file management device.
In the figure, 10 is an operation history recording area, 11 is a FAT,
12 is FATCOPY, 13 is a directory area, 14
Is a directory save area, 15 is a data area, and 16 is a data save area. A management area is composed of the FAT 11 and the directory area 13.

As shown in FIG. 2, the storage area of the flash memory 5 includes an operation history recording area 10, a FAT 11, a FA
It is divided into a TCOPY 12, a directory area 13, a directory save area 14, a data area 15, and a data save area 16, and the data area is composed of a plurality of blocks. It is assumed that the flash memory 5 used by the file management device in the first embodiment has 32 blocks.

As described above, a block is an erase unit of a flash memory. Block (0) is stored in the operation history recording area 10, block (1) is stored in the FAT 11,
Block (2) in FATCOPY 12, block (3) in directory area 13, block (4) in directory save area 14, block (5) to (30) in data area 15, data save area. The block (31) is allocated to 16.

The data area 15 has 12 addresses per block.
Eight sectors are arranged, and each sector is logically mapped by a number from 0 to 3327. FAT11
Has a 2-byte entry for one sector, and the entry data in the initial state (the state where no file exists) is '0000'. When a file that fits in one sector is recorded, for example, 'FFFF' is recorded in the FAT entry of the corresponding sector. When a file is recorded in a plurality of sectors, the number of the next connected sector is recorded in the FAT entry. 'FFFF' is recorded in the last sector of the file. Search for empty sectors
Scans FAT11 and finds that entry data is' 000
The search can be performed by searching for 0's.

FIG. 3 is an explanatory diagram showing the format of the directory area 13. In FIG. 3, reference numeral 20 denotes a directory check byte, which is data for identifying whether the directory is a file-registered directory or an unused directory. Is recorded. It is assumed that the directory check byte 20 is “00” in the initial state. By scanning the directory check byte 20, an unused directory can be searched. 21 is a file name, 22 is a file attribute, 23 is a date, 24 is a start sector number indicating the number of the first sector in which data of the file is recorded, and 25 is a file size.

The operation history recording area 10 is the only data (hereinafter, referred to as an operation identification code) indicating the progress of processing when writing a file, and is necessary for restoring the file management device when an error occurs. This is an area for recording information. Normally, it is in the erased state. The specific recording contents and the timing of recording the operation history will be described later.

In the flash memory 5 used by the file management device, all bits are set to "1" at the time of erasing. The directory save area 14 is the directory area 1
3 is a temporary area used when rewriting the contents of No.3. The data save area 16 is a temporary area used when rewriting the contents of the data area 15. FATC
OPY12 is an area where the same data as FAT11 is recorded. The method of providing the FATCOPY 12 has been often used in the past to improve the reliability of the file management device.

Next, the operation will be described. FIG. 4 is a flowchart showing a file writing process by the file management device. First, upon receiving a file write command from the key input unit 3, the MPU 1 calculates the number of sectors required to store the file. And MPU1
The FAT 11 is scanned to search for empty sectors for the required sectors (step ST1). At this time, if there is no empty sector for the required sector, it is notified that the file cannot be written (step ST17).

When the MPU 1 searches for a necessary sector for a free sector, the operation identification code “A000” indicating that the file is being written to the operation history recording area 10.
And the number of the sector in which the file is to be recorded (step ST2), and the file is recorded in the corresponding sector (step ST3).

The MPU 1 has a directory area 1
Scan the directory check byte 20 of 3
An unused directory is searched (step ST4), and the management data of the directory area 13 is copied to the directory save area 14 (step ST5). Also, MPU1
Adds an operation identification code 'A001' indicating that the directory is being updated to the operation history recording area 10 (step ST6).

The MPU 1 has an operation identification code 'A001'
Is added to the operation history recording area 10, the directory area 13 is block erased (step ST7). Then, the MPU 1 merges the new directory data with the existing directory data and records the merged management data in the directory area 13 (step ST8).

Next, the MPU 1 operates in the operation history recording area 10.
, An operation identification code 'A002' indicating that the FAT is being updated is added (step ST9). MPU
When the operation identification code 'A002' is additionally written in the operation history recording area 10, the block 1 erases the FAT 11 (step ST10). Then, the MPU 1 performs recording of the new FAT entry and writing back of the existing FAT entry (step ST11). That is, in advance, FATCOP
The existing FAT entry copied to Y12 and the new FAT
Merge the AT entry and update the FAT entry.

Next, when the updating of the FAT 11 is completed, the MPU 1 additionally writes an operation identification code 'A003' indicating that the FAT updating is completed in the operation history recording area 10 (step ST12). When the operation identification code 'A003' is added to the operation history recording area 10, the MPU 1 erases the block in the FATCOPY 12 (step ST13).

Then, the MPU 1 copies the management data (FAT entry) of the FAT 11 to the FATCOPY 12 to prepare for the next file writing process (step ST14). Further, the MPU 1 erases blocks in the directory save area 14 (step ST15), and erases blocks in the operation history recording area 10 (step ST1).
6).

Here, consider the case where the power supply is suddenly shut off during the above-described file writing process and the process ends abnormally.
Here, as an example, a description will be given assuming that the power supply is cut off during the processing of step ST8 in FIG. However, in order to clarify the effect of the present invention, first, a case where the restoration process is not performed at all will be described.

When restarting and trying to write the file again, the following situation occurs. First, in step ST1, the FAT11 is scanned for a free sector. At the time of abnormal termination, writing to the FAT entry has not been completed, so the file-written sector is recognized as a free sector. ,
The file is overwritten.

However, the flash memory 5 cannot correctly record data even if data is rewritten without erasing data in an area in which data has been written once. Therefore, the process proceeds as if the data was written normally in the sequence, but a file with incorrect contents is stored in the flash memory 5.

Next, a case in which a recovery process is performed based on the operation history will be described. FIG. 5 is a flowchart showing a recovery process executed at the time of restart. First, MPU1
At the time of restart, the data in the operation history recording area 10 is checked (step ST20).

When no operation identification code is recorded in the operation history recording area 10 (when the operation identification code is erased), the MPU 1 determines that an abnormal end state has not occurred, and performs a recovery process. Ends, and the process proceeds to a normal process. On the other hand, when the record of the operation identification code is left (when the operation identification code is not erased), it is determined that the abnormal end state has occurred, and the processes after step ST21 are executed.

When the MPU 1 recognizes the occurrence of the abnormal end state, the MPU 1 analyzes the operation identification code recorded last in the operation history recording area 10 and determines which of the file writing processes is being executed. It is determined whether the process has been completed (step ST21). In the first embodiment, step S
Since it is assumed that an abnormal end has occurred during the execution of T8, the operation identification code recorded at the end of the operation history recording area 10 is “A001”.

Although the contents of the recovery processing are slightly different depending on the time of occurrence of the abnormal end, the processing shown from step ST22 is a flow chart in the case where the operation identification code 'A001' is detected. If the last recorded operation identification code is a different code, step ST29, step S29
T30, the process proceeds to step ST31.

In step ST21, the MPU 1 determines
When the operation identification code 'A001' is detected, the directory area 13 is block erased (step ST2).
2) The management data in the directory save area 14 is copied to the directory area 13 (step ST23).

The MPU 1 has an operation history recording area 10
The data of the block including the sector indicated by the sector number is copied to the data save area 16 by referring to the sector number recorded in the data save area 16 (step ST24). And M
PU1 performs block erasing of the block including the sector (step ST25), and executes a process of writing back valid data other than the sector (step ST26). That is,
A process of writing back only the data stored in the sectors other than the sector indicated by the sector number among the sectors constituting the block to the original block sector is executed.

When the MPU 1 returns the contents of the data area 15 to the state before the data write processing is executed as described above, the MPU 1 erases the data save area 16 as a block (step ST27), and the operation history recording area The block 10 is erased (step ST28). By the above recovery processing, the data of the sector whose FAT entry indicates a free sector is erased, and the management data of the directory recorded halfway is also erased.

As described above, the operation identification code is sequentially recorded in the operation history recording area 10 during the file writing process.
The number of the sector for recording the file is also the operation history recording area 1
0, and if an abnormal end occurs due to power shutdown, the operation identification code is analyzed when the power is restarted, and the contents of the flash memory 5 are repaired. There is an effect that it is possible to obtain a file management device that uses the flash memory 5 as a storage medium that is resistant to an abnormal end state and has high data reliability.

FIG. 6 is a flowchart showing a file deletion process by the file management device. First, MPU1
Receives a file deletion command from the key input unit 3,
The number of the sector storing the file to be deleted is searched (step ST40). Then, when searching for the sector number, the MPU 1 copies the data of the block including the sector to be deleted to the data save area 16 (step ST41). The MPU 1 records the operation identification code 'A100' indicating that the file is being deleted, the file number of the file, and the number of the block including the sector to be deleted in the operation history recording area 10 (step ST42). ).

The MPU 1 erases the block containing the sector to be deleted (step ST43), and executes a process of writing back valid data other than the file to be deleted (step ST44). In other words, of the sectors constituting the block, only the data stored in the sectors other than the sector to be deleted is written back to the sector of the original block.

Next, when the MPU 1 executes the data write-back processing, the operation identification code 'A101' indicating to the operation history recording area 10 that the data deletion has been completed.
Is added (step ST45). After adding the operation identification code 'A101' to the operation history recording area 10, the MPU 1 copies the management data of the directory area 13 to the directory save area 14 (step ST46).

Next, the MPU 1 operates in the operation history recording area 10.
Is added to the operation identification code 'A102' indicating that the directory is being updated (step ST4).
7). The MPU 1 adds the operation identification code 'A102' to the operation history recording area 10 and
Is erased (step ST48). Also, MP
U1 makes the directory of the deleted file unused, and records the latest management data in the directory area 13 (step ST49). The management data relating to files other than the file to be deleted is stored in the directory save area 14 in the directory area 1.
Copy to 3.

Next, the MPU 1 operates in the operation history recording area 10.
, An operation identification code 'A103' indicating that the FAT is being updated is added (step ST50). MP
When U1 adds the operation identification code 'A103' to the operation history recording area 10, the block erases the FAT11 (step ST51). Also, MPU1 has a new FAT
The entry is recorded and the existing FAT entry is written back (step ST52). That is, FATCO
The existing FAT entry copied to the PY 12 and the new FAT entry are merged to update the FAT entry.

Next, when the updating of the FAT 11 is completed, the MPU 1 adds an operation identification code 'A104' indicating that the FAT updating is completed to the operation history recording area 10 (step ST53). After additionally writing the operation identification code 'A104' in the operation history recording area 10, the MPU 1 erases the block of the FATCOPY 12 (step ST54).

Then, the MPU 1 copies the management data (FAT entry) of the FAT 11 to the FATCOPY 12 in preparation for the next file deletion processing (step ST55). Further, the MPU 1 erases the block of the data save area 16 (step ST56) and erases the block of the directory save area 14 (step ST56).
57), the block is erased from the operation history recording area 10 (step ST58).

Here, consider the case where the power supply is suddenly shut off during the above-described file deletion processing and the processing ends abnormally.
Here, as an example, a description will be given assuming that the power is turned off after the process of step ST43 in FIG. Note that all files stored in the block containing the sector to be deleted have been deleted, so if you restart without performing any recovery processing, if you try to read the file stored in that block, The file in the erased state will be read.

Next, a case in which a recovery process is performed based on the operation history will be described. FIG. 7 is a flowchart showing a recovery process executed at the time of restart. First, MPU1
At the time of restart, data in the operation history recording area 10 is checked (step ST60).

When no operation identification code is recorded in the operation history recording area 10 (when the operation identification code is erased), the MPU 1 determines that an abnormal end state has not occurred, and performs a recovery process. Ends, and the process proceeds to a normal process. On the other hand, when the record of the operation identification code is left (when the operation identification code is not erased), it is determined that the abnormal end state has occurred, and the processing after step ST61 is executed.

When the MPU 1 recognizes the occurrence of the abnormal end state, the MPU 1 analyzes the operation identification code recorded last in the operation history recording area 10 and determines which one of the file deletion processes is being executed. It is determined whether the process has been performed (step ST61). In the first embodiment, step S
Since it is assumed that abnormal termination has occurred after the execution of T43, the operation identification code recorded at the end of the operation history recording area 10 is “A100”.

Although the contents of the recovery processing are slightly different depending on the time of occurrence of the abnormal end, the processing shown after step ST62 is a flowchart when the operation identification code 'A100' is detected. If the last recorded operation identification code is a different code, step ST67, step S67
The process proceeds to T68, step ST69, and step ST70.

MPU 1 determines in step ST 61
When the operation identification code 'A100' is detected, the block including the sector indicated by the sector number is erased with reference to the sector number recorded in the operation history recording area 10 (step ST62). And MPU1
Copies the data copied in the data save area 16 to the above block in step ST41 of FIG. 6 (step ST63).

When the MPU 1 returns the contents of the data area 15 to the state before the data deletion processing is executed as described above, the MPU 1 erases the data save area 16 as a block (step ST64), and also stores the operation history recording area. Then, block 10 is erased (step ST65), and the file deletion process is executed again (step ST66). Since the number of the file to be deleted is recorded in the operation history recording area 10, it can be recognized by referring to the operation history recording area 10. By the above-mentioned restoration processing, the deleted valid file is restored.

As described above, according to the first embodiment, the operation identification code is sequentially recorded in the operation history recording area 10 during the file deletion processing, and the number of the file to be deleted and the file to be deleted are stored. The number of the block including the current sector is also stored in the operation history recording area 10, and if an abnormal end occurs due to power shutdown or the like, the operation identification code is analyzed when the power is restarted, and the contents of the flash memory 5 are restored. Therefore, a file management apparatus using a flash memory 5 having high data reliability as a storage medium, which is resistant to a sudden abnormal termination state such as a sudden power shutdown and the like, can be obtained.

Embodiment 2 In the first embodiment, the case where the operation history recording area 10 is erased as a block when the file writing process or the file deleting process ends normally is described. However, it indicates that the file writing process or the file deleting process ends normally. The operation identification code is added to the operation history recording area 10 so that the operation history recording area 10
When the empty area of the storage area becomes smaller than a certain size, the operation history recording area 10 may be erased as a block. In addition,
The configuration of the file management device and the logical format on the flash memory 5 are the same as those in FIGS. 1 and 2 in the first embodiment.

Next, the operation will be described. FIG. 8 is a flowchart showing a file writing process by the file management device. First, upon receiving a file write command from the key input unit 3, the MPU 1 calculates the number of sectors required to store the file. And MPU1
The FAT 11 is scanned to search for a necessary sector for a free sector (step ST80). At this time, if there is no empty sector for the required sector, it is notified that the file cannot be written (step ST98).

When the MPU 1 searches for empty sectors for the required sectors, it checks the empty area of the operation history recording area 10 (step ST81). If the free area is equal to or smaller than the predetermined size, the MPU 1
Is erased (step ST82). On the other hand, if the free space is equal to or larger than a certain size, the operation history recording area 10
Then, the operation identification code 'A000' indicating that the file is being written and the number of the sector for recording the file are recorded (step ST83), and the file is recorded in the corresponding sector (step ST84).

Then, the MPU 1 stores the directory area 1
Scan the directory check byte 20 of 3
An unused directory is searched (step ST85), and the management data of the directory area 13 is copied to the directory save area 14 (step ST86). Also, MP
U1 adds an operation identification code 'A001' indicating that the directory is being updated to the operation history recording area 10 (step ST87).

The MPU 1 has the operation identification code “A001”
Is added to the operation history recording area 10, the directory area 13 is block erased (step ST88). Then, the MPU 1 merges the new directory data with the existing directory data and records the merged management data in the directory area 13 (step ST89).

Next, the MPU 1 operates in the operation history recording area 10.
, An operation identification code 'A002' indicating that the FAT is being updated is added (step ST90). MP
When U1 adds the operation identification code 'A002' to the operation history recording area 10, the block erases the FAT 11 (step ST91). And MPU1 is a new FA
The recording of the T entry and the writing back of the existing FAT entry are executed (step ST92). That is, in advance, FATC
The existing FAT entry copied to OPY12 and the new FAT entry are merged to update the FAT entry.

Next, when the updating of the FAT 11 is completed, the MPU 1 additionally writes an operation identification code 'A003' indicating that the FAT updating is completed in the operation history recording area 10 (step ST93). When the operation identification code 'A003' is added to the operation history recording area 10, the MPU 1 erases the block in the FATCOPY 12 (step ST94).

Then, the MPU 1 copies the management data (FAT entry) of the FAT 11 to the FATCOPY 12 in preparation for the next file writing process (step ST95). Also, the MPU 1 erases the block of the directory save area 14 (step ST96), and adds an operation identification code “A0FF” indicating that the file writing process has been normally completed to the operation history recording area 10 (step ST97). ).

In the first embodiment, when the operation history recording area 10 is not erased when the power is turned on, the operation identification code is analyzed and the recovery process is executed. In the second embodiment, the operation history is restored. If the operation identification code last recorded in the recording area 10 is not the operation identification code indicating the normal end, the operation identification code is analyzed and the same recovery processing as in the first embodiment is executed. To

In the file deletion process, similarly to the file writing process, when the last operation identification code recorded in the operation history recording area 10 is not the operation identification code indicating normal end, the operation identification is performed. The code is analyzed to execute the same recovery processing as in the first embodiment.

The flash memory 5 has a disadvantage that the time required for data writing and block erasing is longer than the data reading time. As described above, according to the second embodiment, when the file writing process or the file deleting process ends normally, the operation identification code indicating the normal end is added, and the free space in the operation history recording area 10 is added. Since the block erase is performed when the area becomes smaller than a certain size, the overhead of the erase time can be reduced, and as a result,
This has the effect of improving the system throughput.

Embodiment 3 In the first and second embodiments, the case where the operation identification code is sequentially recorded in the operation history recording area 10 during the file writing process or the file deletion process has been described. However, as shown in FIG. At the time of recording, the operation identification code may be recorded in the operation history recording area 10 twice consecutively. The configuration of the file management device and the logical format on the flash memory 5 are the same as those in FIGS. 1 and 2 in the first embodiment.

In the first embodiment, as an example of the abnormal termination during the file writing process, step ST8 in FIG.
The case where the power supply is cut off during the execution of the processing described above has been described. However, in rare cases, the power supply may be shut off while the operation identification code is being recorded. If the power is turned off during the operation history recording, the operation identification code may not be recorded correctly, and the recovery process may not be executed correctly.

FIG. 9 shows that the sector numbers are "0010" and "00".
When writing a file to sectors 11 ',' 0012 ',' 0013 ', and' 0014 ', step S
FIG. 14 is an explanatory diagram showing a recording state of an operation history before executing T3. '0010', '001' following 'A000'
1 ',' 0012 ',' 0013 ', and' 0014 'are the numbers of the sectors for recording the file. 'FFFF' indicates that the data is in the erased state.

On the other hand, FIG. 10 shows that in step ST2,
The number of the sector for recording the file is set in the operation history recording area 1
This shows an example of the recording state of the operation history in the case of abnormal termination during recording to 0. Originally '0
The data to be recorded as “013” is incorrectly “0”.
000 'is recorded. In this case, since the detected operation identification code is “A000”, the restoration process (step ST29) in FIG. 5 is executed. FIG. 11 is a flowchart showing the processing contents of the recovery processing.

The MPU 1 refers to the sector number recorded in the operation history recording area 10 and stores the data of the block including the sector indicated by the sector number in the data save area 16.
(Step ST100). And MPU
The block 1 erases a block including the sector (step ST101) and executes a process of writing back valid data other than the sector (step ST102). That is,
A process of writing back only the data stored in the sectors other than the sector indicated by the sector number among the sectors constituting the block to the original block sector is executed. Then, the MPU 1 erases blocks in the data save area 16 (step ST103), and erases blocks in the operation history recording area 10 (step ST104).

As described above, the recovery process executes the process for erasing the data stored in the sector of the sector number recorded in the operation history recording area 10.
If the recovery processing is executed in the operation history recording state shown in FIG. 10, the data stored in the sector with the sector number '0000' will be erased by mistake.

FIG. 12 is similar to FIG.
9 shows an example of the recording state of the operation history when the operation is abnormally terminated while the number of the sector for recording the file is being recorded in the operation history recording area 10.
Originally, data where “0013” should be recorded twice consecutively is “0000” and “FFFF”.

In the third embodiment, in step ST100 of FIG. 11, only the operation identification code in which the same value is recorded twice consecutively is treated as valid data. Therefore, '0000' is treated as invalid data, and the data of sector number '0000' is not erased by mistake.

Although the operation of the file writing process has been described here, the operation of the file deletion process is the same as that of the file deletion process except that the data to be recorded in the operation history is different.

As described above, according to the third embodiment, at the time of file write processing, the logical address for writing a file and the operation identification code for identifying the progress of processing are stored twice in the operation history recording area 10 successively. The number of the file to be sequentially recorded and deleted during the file deletion process,
Since the number of the block being erased and the operation identification code for identifying the progress of processing are successively recorded twice consecutively in the operation history recording area 10, even if the operation ends abnormally during the operation history recording, the operation is correctly performed. The history can be analyzed and the recovery process can be executed. As a result, an effect is obtained that a file management device using the flash memory 5 as a storage medium with further improved data reliability can be obtained.

Embodiment 4 The file management device according to the fourth embodiment detects an error in the hardware status of the flash memory 5, and when an error is detected, interrupts the file write process or the file delete process and performs a recovery process. Is executed.

The configuration of the file management device and the logical format on the flash memory 5 are the same as those in FIGS. 1 and 2 in the first embodiment. However, in the fourth embodiment, the MPU 1 further configures a detection unit and a control unit.

The flash memory 5 includes a DRAM or an SRA
Unlike M, data writing and block erasing are performed by M
This is executed by issuing a software command from PU1. FIG. 13 is a flowchart showing a program command for executing a process of writing data to the flash memory 5.

First, MPU 1 executes a process of writing a program setup command to flash memory 5 (step ST110). And MPU1
Executes the process of writing data to the program address of the flash memory 5 after writing the program setup command (step ST111).

The MPU 1 waits until the status of the flash memory 5 becomes ready (step ST11).
2) When the status of the flash memory 5 becomes ready, the error status of the flash memory 5 is checked (step ST113). With this, MPU
1 can detect a hardware error of the flash memory 5. Therefore, when a hardware error of the flash memory 5 is detected, the subsequent file writing process is interrupted, and the process shifts to a recovery process based on the operation history.

FIG. 14 is a flowchart showing a block erase command for executing block erasure on the flash memory 5. First, the MPU 1 executes a process of writing a block erase / setup command to the flash memory 5 (step ST12).
0). After writing the block erase / setup command, the MPU 1 executes a process of writing a block erase / confirmation command to the flash memory 5 (step ST121).

MPU 1 waits until the status of flash memory 5 becomes ready (step ST12).
2) When the status of the flash memory 5 becomes ready, the error status of the flash memory 5 is checked (step ST123). With this, MPU
1 can detect a hardware error of the flash memory 5. Therefore, when a hardware error of the flash memory 5 is detected, the subsequent file deletion processing is interrupted, and the processing shifts to the recovery processing based on the operation history.

As described above, according to the fourth embodiment, when an error in the hardware status of the flash memory 5 is detected, the file writing process or the file deleting process is interrupted, and the recovery process is executed. Therefore, there is an effect that a file management device using the flash memory 5 as a storage medium with further improved data reliability can be obtained.

Embodiment 5 FIG. In the fourth embodiment, when an error in the hardware status of the flash memory 5 is detected, the file writing process or the file deleting process is interrupted, and the recovery process is executed. A timer may be provided to start measurement when issuance is performed, and if there is no response from the flash memory 5 for a certain period of time, the file writing process or the file deleting process may be interrupted and the recovery process may be executed. The configuration of the file management device and the logical format on the flash memory 5 are the same as those in FIGS. 1 and 2 in the first embodiment.

Step ST1 in FIGS. 13 and 14
In steps 12 and 122, the process of waiting until the status becomes ready polls the status read from the flash memory 5 and checks a specific bit in the status. If the particular bit does not become ready due to some problem, the program may not be able to shift from polling processing to the next processing.

FIG. 15 is a flowchart showing the contents of processing of a program command in the fifth embodiment. First, MPU 1 executes a process of writing a program setup command to flash memory 5 (step ST130). Then, when writing the program setup command, the MPU 1 executes a process of writing data to the program address of the flash memory 5 (step ST131). At that time, M
PU1 starts a timer (step ST132).

The MPU 1 is similar to the fourth embodiment,
While waiting until the status of the flash memory 5 becomes ready (step ST133), the value of the timer is checked during the standby (step ST134). When the value of the timer exceeds a certain value, the status of the flash memory 5 is changed. Even in the non-ready state, the file write processing is interrupted and the recovery processing is executed.

However, as long as the value of the timer is equal to or less than the predetermined value, the standby state is continued, and when the status of the flash memory 5 becomes ready, the same as in the fourth embodiment,
The error status of the flash memory 5 is checked (step ST135). If an error is detected, the file writing process is interrupted, and the recovery process is executed.

In the fifth embodiment, the timer is started during the file writing process, and the recovery process is executed when the value of the timer exceeds a predetermined value. It is sufficient to start the timer after the process of step ST121 in, and the recovery process can be started in the same manner as the file writing process.

As described above, according to the fifth embodiment, the timer for starting measurement when a command is issued to the flash memory 5 is provided. Alternatively, since the file deletion processing is interrupted and the recovery processing is executed, it is possible to obtain a file management apparatus using the flash memory 5 as a storage medium with further improved data reliability.

Embodiment 6 FIG. 2. Description of the Related Art Some recent flash memories include two banks, and can read data from the other bank during writing or deleting of one bank. The above function is called a dual operation function or a background operation function. The file management device according to the sixth embodiment uses the flash memory 5 having the above functions to improve the performance of the processing time in the file writing process and the file deleting process.

FIG. 16 is an explanatory diagram showing a logical format on the flash memory 5 in the file management device. The flash memory 5 is divided into a bank (1) and a bank (2), and the bank (1) has a block (0).
(15), but the bank (2) has the block (16)
(31) is assigned. When write processing or deletion processing is being performed on bank (1), bank (2)
Can be read, and conversely, data can be read from the bank (1) while writing or deleting is being performed on the bank (2).

In the sixth embodiment, block (0) is stored in the operation history recording area 10, block (1) is stored in the FAT11, and block (29) is stored in the FATCOPY12.
However, the directory area 13 has a block (2), the directory save area 14 has a block (30), the data area 15 has blocks (3) to (28), and the data save area 16 has a block (31). Is assigned.
The configuration of the file management device is the same as that of the first embodiment shown in FIG. However, in this sixth embodiment, MP
U1 further constitutes reading means.

As described in the previous embodiment, in the file writing process, the file deleting process, the restoring process, etc.
A process of copying a FAT, a directory, a file, and the like from an arbitrary block to another block is frequently executed. FIG. 17 is an explanatory diagram for explaining an operation at the time of executing a copy process when a flash memory having no dual operation function is used.

Data of a certain size is read from the copy source block, and the data is stored in the RAM 8 or the RAM inside the MPU 1.
Issue a command to write data to another block.
The read operation and the write operation are repeatedly executed to copy one block of data. The write time takes a longer time than the read time, but the MPU 1 waits until a status indicating that the write operation has been completed is obtained,
Shift to the next data read operation.

FIG. 18 is an explanatory diagram for explaining the operation at the time of executing copy processing when using a flash memory having a dual operation function. FAT1
1, some blocks of the directory area 13 and the data area 15 are configured in a bank (1), and FATCOPY
12, directory save area 14 and data save area 1
Reference numeral 6 denotes a bank (2).

Therefore, when data of bank (1) is copied to bank (2), or conversely, data of bank (2) is copied to bank (1), as shown in FIG.
Since the read operation and the write operation can be executed in an overlapping manner, the data processing time can be reduced. As described above, the data processing time is reduced by the dual operation function, taking the data copy processing between blocks as an example.
It is also possible to apply to other processing such as performing file writing and searching for an unused directory in parallel.

As described above, according to the sixth embodiment, the flash memory 5 having the dual operation function is used, and the logical format is set so that the blocks where data copying and the like are frequently performed are in separate banks. , The data processing time is shortened and the system throughput is improved.

[0114]

As described above, according to the present invention, when the writing means executes the writing process or the updating process, the identification code indicating the processing content is recorded in the operation history recording area of the flash memory. An operation history recording means for erasing the identification code when the writing process or the updating process ends normally is provided, and when the identification code is recorded in the operation history recording area of the flash memory, the identification code is analyzed. Then, since the data stored in the data area and the management area is configured to be restored, an abnormal state such as a power shutdown occurs when the writing unit is executing the writing process or the updating process. Also, there is an effect that file operations can be normally resumed without destroying files and data.

According to the present invention, when the writing means executes the writing process or the updating process, the identification code indicating the processing content is recorded in the operation history recording area of the flash memory, and the writing process or the updating process is performed. Is normally provided, an operation history recording means for recording an identification code indicating the normal end in the operation history recording area is provided. If the identification code indicating the normal end is not recorded in the operation history recording area of the flash memory, the processing is performed. Since the configuration is such that the identification code indicating the content is analyzed and the data stored in the data area and the management area are restored, when the writing unit is executing the writing process or the updating process, the power supply is shut off. Even if an abnormal state occurs, file operations can be normally resumed without destroying files and data.

According to the present invention, the recovery processing is executed in accordance with the analysis result of the identification code, and the data stored in the data area and the management area is restored to the contents before the writing processing or the updating processing is executed. Since it is configured to return, a flash memory that is resistant to a sudden abnormal termination state such as a sudden power shutdown and has high data reliability can be obtained.

According to the present invention, when the deletion means executes the deletion processing or the update processing, the identification code indicating the processing content is recorded in the operation history recording area of the flash memory, and the deletion processing or the update processing ends normally. Then, an operation history recording means for erasing the identification code is provided, and if the identification code is recorded in the operation history recording area of the flash memory, the identification code is analyzed and the data area and the management area are analyzed. Since the stored data is configured to be restored, even if an abnormal condition such as power shutdown occurs while the deletion unit is executing the deletion process or the update process, the files and data are not destroyed, There is an effect that the file operation can be normally resumed.

According to the present invention, when the deletion means executes the deletion processing or the update processing, the identification code indicating the processing content is recorded in the operation history recording area of the flash memory, and the deletion processing or the update processing ends normally. Then, an operation history recording means for recording an identification code indicating a normal end in the operation history recording area is provided, and when the identification code indicating the normal end is not recorded in the operation history recording area of the flash memory, the processing contents are indicated. Since the system is configured to analyze the identification code and recover the data stored in the data area and management area, an abnormal state such as power shutdown occurs when the deletion unit is executing the deletion or update processing. Even so, there is an effect that file operations can be normally resumed without destroying files and data.

According to the present invention, the recovery processing according to the analysis result of the identification code is executed to return the data stored in the data area and the management area to the contents before the deletion processing or the update processing was executed. With such a configuration, a flash memory which is resistant to a sudden abnormal termination state such as a sudden power shutdown and has high data reliability can be obtained.

According to the present invention, the same identification code is
The system is configured to treat the identification code as a valid identification code only when it is recorded consecutively, so that even if it ends abnormally while recording the operation history, it correctly analyzes the operation history and performs recovery processing. Can be executed, and as a result, it is possible to obtain a flash memory with further improved data reliability.

According to the present invention, when the detecting means detects a hardware error, the processing of the writing means is stopped and the processing of the restoring means is started, so that the flash having further improved data reliability is provided. There is an effect that a memory can be obtained.

According to the present invention, when the detecting means detects a hardware error, the processing of the deleting means is stopped and the processing of the restoring means is started. Therefore, the flash memory with further improved data reliability. There is an effect that can be obtained.

According to the present invention, when the detecting means cannot receive the hardware error status signal from the flash memory for a certain period of time or more, the detecting means executes the same processing as when detecting the hardware error. Therefore, even if a failure occurs in the flash memory and a hardware error status signal cannot be received, the recovery unit can execute the recovery process, and as a result, data reliability is further improved. There is an effect that a flash memory can be obtained.

According to the present invention, when the writing means is writing file data to one bank, the reading means for reading data from the other bank is provided, so that the data processing time is reduced. This has the effect of improving the system throughput.

According to the present invention, when the deletion means is deleting a sector from one bank, the reading means for reading data from the other bank is provided, so that the data processing time is reduced, and This has the effect of improving throughput.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a file management device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a logical format on a flash memory 5 in the file management device.

FIG. 3 is an explanatory diagram showing a format of a directory area 13;

FIG. 4 is a flowchart illustrating a file writing process performed by the file management device.

FIG. 5 is a flowchart illustrating a recovery process executed at the time of restart.

FIG. 6 is a flowchart illustrating a file deletion process performed by the file management device.

FIG. 7 is a flowchart illustrating a recovery process executed at the time of restart.

FIG. 8 is a flowchart illustrating a file writing process performed by the file management device.

FIG. 9 is an explanatory diagram showing a recording state of an operation history before executing step ST3.

FIG. 10 is an explanatory diagram showing an example of a recording state of an operation history when an abnormal end occurs while the number of a sector for recording a file is being recorded in the operation history recording area 10;

FIG. 11 is a flowchart illustrating processing contents of a recovery processing.

FIG. 12 is an explanatory diagram showing an example of a recording state of an operation history when an abnormal end occurs while the number of a sector for recording a file is being recorded in the operation history recording area 10;

FIG. 13 is a flowchart showing a program command for executing a process of writing data to the flash memory 5;

FIG. 14 is a flowchart showing a block erase command for executing block erasure on the flash memory 5;

FIG. 15 is a flowchart showing processing contents of a program command.

FIG. 16 is an explanatory diagram showing a logical format on the flash memory 5 in the file management device.

FIG. 17 is an explanatory diagram illustrating an operation at the time of executing a copy process when a flash memory having no dual operation function is used.

FIG. 18 is an explanatory diagram illustrating an operation at the time of executing copy processing when a flash memory having a dual operation function is used.

FIG. 19 is an explanatory diagram showing a logical format on a flash memory in a conventional file management device.

FIG. 20 is a flowchart showing processing contents of a conventional file management device.

[Explanation of symbols]

1 MPU (writing means, deletion means, operation history recording means,
Recovery means, detection means, control means, reading means), 2 RO
M, 3 key input section, 4 I / F section, 5 flash memory, 6 VRAM, 7 display section, 8 RAM, 10
Operation history recording area, 11 FAT (management area), 12
FATCOPY, 13 directory area (management area), 14 directory save area, 15 data area, 16 data save area, 20 directory check byte, 21 file name, 22 file attribute, 2
3 Date, 24 starting sector number, 25 file size.

Claims (12)

[Claims] An empty sector in a data area of the flash memory is searched by referring to management data stored in a management area of the flash memory, and file data is written to the empty sector. A writing unit for updating the writing process, and when the writing unit executes a writing process or an updating process, an identification code indicating the processing content is recorded in an operation history recording area of the flash memory;
When the writing process or the updating process ends normally, the operation history recording means for erasing the identification code and, if the identification code is recorded in the operation history recording area of the flash memory, analyze the identification code. And a recovery means for recovering data stored in the data area and the management area. 2. Searching for a free sector in a data area of the flash memory with reference to management data stored in a management area of the flash memory, writing file data to the free sector, and A writing unit for updating the writing process, and when the writing unit executes a writing process or an updating process, an identification code indicating the processing content is recorded in an operation history recording area of the flash memory;
When the writing process or the updating process is completed normally, an operation history recording means for recording an identification code indicating normal completion in the operation history recording area, and an identification code indicating normal completion in the operation history recording area of the flash memory. If not, a file management apparatus comprising: a recovery unit that analyzes an identification code indicating the processing content and recovers data stored in the data area and the management area. 3. The recovery means executes recovery processing according to the analysis result of the identification code, and restores the data stored in the data area and the management area to the contents before the write processing or the update processing is executed. 3. The file management apparatus according to claim 1, wherein the file management apparatus returns the file management information. 4. A block in a data area including a sector to be deleted is searched by referring to management data stored in a management area of the flash memory, and a sector to be deleted is deleted from the block. Deletion means for updating management data, and when the deletion means executes deletion processing or update processing, an identification code indicating the content of the processing is recorded in the operation history recording area of the flash memory, and the deletion processing or update processing is performed. When the operation is normally completed, the operation history recording means for erasing the identification code, and when the identification code is recorded in the operation history recording area of the flash memory, the identification code is analyzed, and the data area and the management area are analyzed. File management device comprising: recovery means for recovering data stored in a file. 5. A block in a data area including a sector to be deleted is searched for by referring to management data stored in a management area of the flash memory, and a sector to be deleted is deleted from the block. Deletion means for updating management data, and when the deletion means executes deletion processing or update processing, an identification code indicating the content of the processing is recorded in the operation history recording area of the flash memory, and the deletion processing or update processing is performed. An operation history recording unit that records an identification code indicating a normal end in the operation history recording area when the operation ends normally; and a processing content when an identification code indicating a normal end is not recorded in the operation history recording area of the flash memory. Recovery means for analyzing the identification code indicating the data area and recovering the data stored in the data area and the management area. File management device. 6. The recovery means executes recovery processing according to the analysis result of the identification code, and returns the data stored in the data area and the management area to the contents before the deletion processing or the update processing was executed. The file management device according to claim 4 or 5, wherein 7. When the operation history recording means records the same identification code twice consecutively in the operation history recording area, the recovery means performs the identification only when the same identification code is recorded twice consecutively. 7. The file management apparatus according to claim 1, wherein the code is treated as a valid identification code. 8. A detecting means for detecting a hardware error of the flash memory, and a control means for stopping the processing of the writing means and starting the processing of the recovery means when the detecting means detects the hardware error. The file management device according to claim 1, wherein 9. A detecting means for detecting a hardware error of the flash memory, and a control means for stopping the processing of the deleting means and starting the processing of the restoring means when the detecting means detects the hardware error. The file management device according to claim 4, wherein the file management device is a file management device. 10. When the detecting means cannot receive a hardware error status signal from the flash memory for a certain period of time or more, the control means executes the same processing as when the detecting means detects a hardware error. The file management device according to claim 8 or 9, wherein 11. When the flash memory is composed of two banks, when the writing means is writing file data to one bank, reading means for reading data from the other bank is provided. 4. The file management device according to claim 1, wherein: 12. When the flash memory is composed of two banks, reading means for reading data from the other bank is provided when the deleting means deletes a sector from one bank. The file management device according to any one of claims 4 to 6, wherein