JP2000222292A - Data managing method utilizing flash memory - Google Patents

Abstract

PROBLEM TO BE SOLVED: To store data to be held even in a state of power source off in the same flash memory together with a program, for example. SOLUTION: A data storage block 2 is secured in the blocks of a flash memory 12, data to be held even at the time of power source off are stored, erasing processing is separated and only write processing of data is performed by a system of rotation using the plural data storage blocks 2 at the time of reloading the data. To that end, the data storage block 2 is composed of a block managing area 3, a data managing area 4 and a data storage area 5, the state information of the present block and the erasing states of the other blocks are stored in the block managing area 3, the data managing area 4 is composed of data managing tables 20 as many as the number of data areas in the data storage area 5, and the data storage area 5 is composed of plural data areas in the equal size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data management method and apparatus using a flash memory, and more particularly, to a flash capable of storing a program and data that must be retained without power supply in the same flash memory. The present invention relates to a data management method using a memory.

[0002]

2. Description of the Related Art In a conventional portable electronic device, particularly a portable telephone, a battery is used as a power supply source, and there is a possibility that power supply may be lost. Therefore, important data such as a telephone number is stored. The memory uses an EEPROM which is a non-volatile memory capable of holding data even without power supply. In addition, a rewritable flash memory is used as a nonvolatile memory for storing a program in order to shorten product development by shortening a product shipping cycle. In portable electronic devices, miniaturization of individual parts and reduction of the number of parts used are considered necessary along with reduction in size and weight.

[0003]

Therefore, conventionally, EEP
If the data stored in the ROM can be stored in the flash memory storing the program, EE
Although the PROM can be eliminated and the size and weight can be reduced, the flash memory has some restrictions due to the structure of the storage element, and has the following problems.

The first problem is that data cannot be written in a flash memory unless it is in an initial state. Therefore, in order to rewrite previously written data, the data cannot be written without first erasing the data. Therefore, data at an arbitrary address cannot be arbitrarily rewritten. Erasing unit is not several bytes but several tens of kilobytes.
The data is written in blocks or chips of several hundred kilobytes, and the data writing speed or the erasing speed is much longer than the data reading speed. In particular, the erasing time is longer because the erasing unit is longer. To rewrite data, the flash memory is erased and then returned to the initial state after the data to be rewritten is temporarily saved somewhere in the unit of erasing, and the data which is not desired to be erased is changed from the save destination to the initial state. Since it is necessary to write to a memory and then to a new portion to be written, rewriting takes time.

[0005] The second problem is that data cannot be read during data writing or erasing. Therefore, if data conventionally stored in the EEPROM is simply allocated to the flash memory, there is a restriction on data reading every time data is rewritten, which makes it difficult to operate the program as before. .

A third problem is that, in a portable electronic device such as a portable telephone, the battery may be unexpectedly removed due to its structure, but it takes time to write and erase data. It is easily conceivable that the power supply is cut off during writing and erasing. Further, when the power is supplied again after the power supply is cut off and the flash memory operates, the flash memory does not remain in the state of being writing or erasing. Therefore, especially in erasing, the storage elements are not erased all at once, so checking only a part of the data does not mean that the entire erasing unit has been erased. Means that it is necessary to read the data of the entire erasure unit, which takes time.

Therefore, an object of the present invention is to provide the first, second,
By solving the third problem, there is provided a data management method using a flash memory so that data that must be retained even in a power-off state can be stored together with, for example, a program in the same flash memory. It is in.

[0008]

A data management method using a flash memory according to the present invention has a data storage area for storing data which needs to be held even when the power is turned off in a data unit of a data area size. A data storage block is secured by a block serving as an erase unit of the flash memory, and for each data storage area, information indicating a state of the data storage area and information of the data stored in the data storage area; The data is managed using information indicating the state of the own block and the state of the other block for each of the blocks.

In a data management method using a flash memory according to the present invention, a data storage area is secured in a block serving as an erasing unit of the flash memory, and information indicating the state of the data storage area for each data storage area and the data storage area. Information on the data stored in the data storage area,
Using the information indicating the status of the own block and the other blocks for each block, data "rewrite" stores data in a data storage area and indicates "stored" corresponding to the data storage area. This is performed by storing information indicating the type of the data and the information and overwriting the information indicating “no data storage” corresponding to the data storage area in which the old data exists, and accompanying the “rewriting” of the data in the flash memory. Eliminating the erasing process to the initial state at the time of "rewriting" the data eliminates the time required for "rewriting" of the data in the flash memory, and saves the data that must be retained even when the program and the power are off. Can be stored in the same flash memory.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below. The data management method using the flash memory according to the present embodiment is suitable for application to a rewritable memory of a program, particularly to a portable electronic device having a flash memory, and the program is retained without the program and power supply. Data to be stored is stored in the same flash memory, and the EEPROM can be deleted when applied to a portable electronic device, thereby realizing a reduction in size and weight.

In the following description, a portable telephone will be described as an example of a portable electronic device using a flash memory. FIG. 1 is a block diagram illustrating a configuration of a mobile phone to which the data management method according to the present embodiment is applied. A mobile phone 10 having a flash memory in which the program can be rewritten has a CPU 11, a flash memory 12, a RAM 13, a control unit 14, a radio unit 15,
It is composed of an antenna 16, a battery 17, and the like.

The CPU 11 is a wireless unit 1 of the mobile phone 10.
5 and the like to communicate via a base station (not shown) and to control each unit. The flash memory 12 is divided into blocks 0 to n, each block of which is several tens of kilobytes to several hundreds of kilobytes, and stores programs and data that must be retained even when power is turned off. is there. As a reference of the flash memory, there is a data sheet of a flash memory MBM29LV800B manufactured by Fujitsu. The RAM 13 is used as a temporary storage area for general-purpose data, and is used for writing and reading. When the power is not supplied, the RAM 13 does not need to hold the data.
AM is used.

The control unit 14 controls each unit as a portable telephone, for example, by communicating with a CPU 11 via a base station (not shown). The radio unit 15 is for performing communication with the base station by radio frequency. The antenna 16 is for transmitting and receiving signals to and from the base station by radio frequency. Battery 17 is
It serves as a power supply for supplying power to each section of the mobile phone 10.

The mobile phone 10 communicates with a base station (not shown) via the antenna 16 so that the CPU 11, the flash memory 12, the RAM 13, and the control unit 14 control the radio unit 15 to perform communication. The flash memory 12 stores programs and data that must be retained even when power is turned off. The RAM 13 is written and read as a temporary storage location for general-purpose data that does not need to be held when power is not supplied.

FIG. 2 is an explanatory diagram showing the configuration of the flash memory 12 in the mobile phone 10. As shown in FIG. The flash memory 12 is divided into blocks such as block 0 to block n. One block is number 10
Kilobytes to hundreds of kilobytes. The flash memory 12 stores programs and data that must be retained even when the power is turned off. As an area for storing data, a data storage block 2 is reserved for each block.

In general, due to the configuration of the storage element of the flash memory, arbitrary data cannot be written unless the block is erased and set to the initial state. As a data rewriting process, the data before rewriting is temporarily saved somewhere in the unit of erasing, then erased, data not to be erased is written from a save destination, and then a step of writing new data to be written is performed. For this reason, the writing process requires time. Thus, in the present embodiment, erasing processing is performed separately, and only data writing processing is performed at the time of data rewriting, so that data rewriting processing is performed efficiently. For this purpose, a plurality of data storage blocks 2 are used in rotation.

In this embodiment, a case will be described in which three blocks n-2 to n shown in FIG. 2 of the flash memory 12 are secured as data areas for storing data. The data storage block 2 obtained by enlarging the block n-1 of the flash memory 12 includes a block management area 3, a data management area 4, and a data storage area 5. The block management area 3 stores status information such as whether the current block is in use, unused, or used. Further, the erase status of other blocks is stored. The erasure status is information such as whether erasure is in progress or erasure is completed.

The data storage area 5 is an area for storing data, and is composed of a plurality of data areas of an appropriate uniform size. For example, assume that the size of one data area is 16 bytes. As shown in FIG. 2, the data areas are numbered in the order of use (a) as shown in FIG. 2, and the data areas are used in the order shown in the use order (a).

The data management area 4 has a data storage area 5
And the same number of data management tables 20 as the number of data areas. The data management table 20 is configured with one data unit size of the flash memory. For example, D15
To D0, the number of data bits for one address is one.
Since it is 6 bits, the size of one data unit is 16 bits. Here, one data unit size is 16 bits. That is, one data management table has 16 bits.

The numbers shown in the data management area 4 are the numbers of the data management table 20. Then, numbers are assigned in the order of the use order (b), and the data areas have the same number as the number. For example, the number assigned to the data management table 20 of the data area m is:
M in the data management area 4. Data management table 2
0 stores management information such as whether the data stored in the data storage area 5 is valid or invalid, whether data is being written, and information on what data is stored. A data number is stored as information on what data is stored in the data area. In this method, similar data such as rewriting at the same timing in data to be stored are previously collected for each data number equal to the data area, and the data group is numbered. By storing this number in the data management table 20, information on what data is stored in the data area is stored. In addition, by regularly arranging the data area and the data management table 20, it is possible to easily calculate the head address of the data area from the address of the data management table 20, so that it does not take time to read necessary data. To

FIG. 3 shows the data management table.
This will be described with reference to FIG. FIG. 3 is an explanatory diagram showing the configuration of this data management table. The data management table 20 shown in FIG. 3 is an example in the case where the flash memory 12 has one data unit of 16 bits. This data management table 20
As shown in (1), management is performed by giving meaning to each bit. The reason for giving meaning in bit units is that the flash memory 1
This is because data cannot be arbitrarily rewritten due to the nature of 2. When the flash memory 12 is viewed in bit units, it is impossible to overwrite the data in the initial state with the data opposite to the initial state due to the structure of the storage element, and it is necessary to erase the data in the initial state. , It is possible to overwrite the same data as the initial state with the opposite data.
By utilizing this property, it is possible to manage information such as whether data is being written or data in the data area is valid by changing the information in bit units.

By providing the data management area 4 for storing the use state of the data area in the block, the state of the data area can be searched by searching only the data management area 4 so that the capacity of one block depends on the capacity. Without being performed, the use state of the data area can be grasped, and required data can be easily detected.

Next, the block management area 3 shown in FIG. 2 will be described with reference to FIG. FIG. 4 is an explanatory diagram showing this block management area. The block management area 30 shown in FIG. 4 is the same as the block management area 3 in FIG.
The block management area 30 includes a current block use presence / absence table 31 shown in FIG. 5 and an erase status table 32 of each block shown in FIG.

The current block use / non-use table 31 and each block erasure status table 32 are also the data management table 2.
Similar to 0, management is performed by giving meaning to each bit. Each table is composed of one data unit size of the flash memory. Here, as in the data management table 20, the size of one data unit is 16 bits.

When a flash memory is used as a program rewritable memory, as described above, (1) the flash memory 12 is divided into blocks of several kilobytes to several hundreds of kilobytes. Until after erasing in units and initializing, arbitrary data can not be written, and several hundred μ
(2) In the data rewriting process, data to be rewritten for each erase block is temporarily saved to a save destination, and then the block is erased and rewritten. Writing data that has not been saved from the save destination, and then writing the new data to be written takes a long time in the processing,
(3) When the flash memory 12 is viewed in bit units, it is impossible to “overwrite” data in the initial state on data opposite to the initial state due to the structure of the storage element. However, there is a property that it is possible to “overwrite” data opposite to the initial state on the same data as the initial state.

For this reason, the above (1), (2), (3)
From the point of view, as shown in FIG.
A block management area 3 for data management, a data management area 4 and a data storage area 5 for storing data are provided therein. The data storage area 5 is composed of a plurality of equally sized data areas, and the data management table 20 of FIG. 3 corresponding to each data area is provided in the data management area 4 shown in FIG.

When performing "rewriting" of data, in addition to storing data in the data area, information indicating data storage and information of what data are stored in the corresponding data management table 20, Information indicating no data storage is overwritten in the data management table 20 corresponding to the data area in which the old data exists, utilizing the property of the flash memory 12. In this way, the configuration is such that data can be "rewritten" with only a minimum data write process.

A plurality of blocks for storing data are used in rotation. The valid blocks among the blocks to be rotated are identified by the current block use presence / absence table 31 shown in FIG. 5 in the block management area 3 (same as the block management area 30 in FIG. 3) provided in each block. When a valid data area exists in a block, data representing a valid block is written to the current block use presence / absence table 31, and when changing from a valid block to an erasable block, the property of the flash memory 12 is utilized. Then, the data indicating the erasable block is "overwritten" in the current block use presence / absence table 31. In this way, while the blocks that store data are used in rotation, by managing whether each block is valid or invalid, the data rewriting process is performed separately from the erasing process, and only the data writing process is performed during data rewriting. The configuration should be such that it is sufficient. As a result, the efficiency of the writing process is improved, and the data and the program that must be held even without power supply to the same flash memory can coexist.

Further, by providing the data management area 4 for storing the use state of the data area in the block, the state of the data area can be searched for only the data management area 4. The configuration is such that the use state of the data area can be grasped without being influenced, and required data can be easily detected.
In addition, by regularly arranging the data area and the data management table 20, it is possible to easily calculate the head address of the data area from the address of the data management table. The configuration is such that the difference in the capacity of the memory blocks can be easily accommodated.

As described above, the battery may be unexpectedly removed due to the structure of the portable electronic device, and the power supply may be cut off during data writing and erasing. Further, when the power is supplied again after the power supply is cut off and the flash memory operates, the flash memory does not remain in the state of being writing or erasing. In particular, in erasing, the memory elements are not erased all at once, so checking only a part of the data does not mean that the entire erased block has been erased. It is necessary to read the data of the entire block, which takes time. Therefore, utilizing the properties of the flash memory 12, when writing data to the data area, write the start of writing to the data management table 20 before writing to the data area, and after writing to the data area, write over the write completion. "Yes. At the time of block erasure, erasure is started before erasure by utilizing the properties of the flash memory 1 in the block erasure status table 32 shown in FIG. Is written, and the completion of erasing is overwritten by the completion of erasing.

By leaving the data writing and erasing statuses as described above, it is possible to easily confirm whether or not the erasing has been completed, even after power interruption during data writing or erasing or interruption of processing due to resetting. .

Next, the operation will be described. First, the "writing" of data will be described with reference to the flowcharts shown in FIGS. Here, a flash memory in which the initial state of the storage element is “1” will be described as an example. Further, the blocks n-2 to n of the flash memory 12 shown in FIG.
The description will be made assuming that the rotation is performed in the order of -2.

First, prior to "writing" data to the data area, a block to be used in the flash memory 12 is determined. This use block is determined by checking the current block use presence / absence table 31 shown in FIG. 5 of the block management area 30 of each block shown in FIG. 4 and detecting a block that can be made “valid (in use)”. As a result, when there is no block that can be set to “valid (in use)”, the current block use presence / absence table 3 in the block management area 30 of the unused block to be used next is rotated by block rotation.
1 is written as "valid (in use)" (step S in FIG. 7).
10, step 11). At this time, the state of the current block use table 31 changes from the state of the current block use table indicated by reference numeral 40 to the state of the current block use table indicated by reference numeral 41 as shown in FIG. 7B.
On the other hand, if the block can be made “valid (in use)”, the next step S11 is omitted.

After the used block is determined in this way, next, as shown in the flowchart of FIG. 9, the data management area 4 in the used block is confirmed from the lowest data management table 20 in the use order. An unused data area is detected (step S30).

Next, "write start" and a data number to be stored in the data area are written in the data management table 20 corresponding to the detected unused data area (step S31). At this time, the state of the data management table 20 changes from the data management table indicated by reference numeral 60 to the data management table indicated by reference numeral 61.

Next, data is written to the data area (step S32). When the "writing" of the data to the data area is completed (step S33), "valid (writing completed)" is written to the data management table 20 (step S34). The state of the data management table 20 at this time is the state of the data management table indicated by reference numeral 62.

If the data "write" is performed to update the data of the data number which has already been stored, the data management table 20 corresponding to the data area in which the old data exists contains "invalid ( (Used) is written (step S35). At this time, the state of the data management table 20 is the state of the old data management table indicated by reference numeral 63.

When a write error occurs during data writing to the data area, D13 and D12 of the data management table 20 are set to "0", and a record in which the write error occurred at the time of writing the data area is left.

If all the data areas of the current block have been used, the data is stored in the data area of the next block in the rotation order.

These operations are repeated to “write” data.
By performing "rewriting", data can be rewritten without performing an erasing process. Further, since the data unit to be written is the data area size, it is sufficient to write necessary minimum data at the time of data rewriting, and the writing efficiency is improved.

Next, "erase" will be described with reference to FIGS.
This will be described with reference to the flowchart shown in FIG. Since blocks are used for rotation, blocks using all data areas need to be erased. Therefore, first, it is determined whether or not all data areas are used and there is no free space in the data area (step S20). If the data area is "no data area free", necessary data before erasing is described above. Copy to the next block by writing method.
However, this processing does not need to be continued to the data writing processing. When the copying is completed, the blocks using all the data areas can be erased, so "invalid (used)" is written in the current block use presence / absence table 31 (step S21). At this time, the state of the current block use / non-use table 31 is changed from the state of the current block use / non-use table indicated by reference numeral 50 to the state of the current block use / non-use table indicated by reference numeral 51. As a result, the block becomes a block waiting for erasure.

Here, the currently used block is referred to as a block n.
The case where the block n-1 is erased will be described as an example. As shown in the flowchart of FIG. 10, the current block use presence / absence table 31 in the block management area 30 of each block is checked, and a search is made for an invalid “used” block (step S40). Since block n-1 is waiting for erasure, "erasure start" is written in the erasure status of block n-1 in the block management area in block n (step S41). At this time, the state of the erasure status of the block n-1 in the block n is based on the erasure status of the block n-1 indicated by the reference numeral 70 and the block n-1 indicated by the reference numeral 71.
1 is erased. Next, block n-1 is erased (step S42). Then, completion of the erasure is monitored (step S43). When the erasure is completed, the block n-
1 is written in the erase status (step S4).
4). At this time, the state of the erase status of block n-1 is
The erasure state of the block n-1 indicated by the reference numeral 72 is set.

When an error occurs during erasing, D13 and D12 of the erasing status of block n-1 are set to "0", and a record in which an erasing error has occurred during the block erasing is left. The erasing process does not need to be continued from the data writing process. By repeating these steps and erasing, the erasing process can be performed separately from the “writing” of data.

Also, due to the structure of the mobile phone, the battery may be unexpectedly removed, and the power supply may be cut off during data writing and erasing. For example, at the time of block erasure, the start of erasure before erasure is performed by utilizing the characteristics of the flash memory 12 in the block erasure status table 32 in the block management area 30 of the block other than the block to be erased. The end of erasing is overwritten by the end of writing and erasing. By leaving the "write" and "erase" statuses of the data in this manner, it is possible to easily confirm the erasure completion status of the erasure target block even after power interruption during data writing and erasure or interruption of processing due to occurrence of a reset. Becomes possible.

As described above, according to the present embodiment, by setting the data unit to be written to be the data area size,
Since there is no need to rewrite unchanged data, the time required for the writing process can be reduced, restrictions for operating programs in the same memory can be reduced, and a flash memory suitable for portable electronic devices such as a mobile phone is used. There is an effect that a data management method can be provided.

Further, by using a data area size as a data unit to be written and using a plurality of blocks in the flash memory as a data area by rotation, erasing is not required at the time of writing data, and erasing can be performed at a desired timing. It is possible to reduce restrictions for operating the program and to provide a data management method using a flash memory suitable for a portable electronic device such as a mobile phone.

By storing the states before and after data writing and erasing in the same flash memory, the status as to whether data is being written or erased in the nonvolatile memory irrespective of whether power is supplied or not is provided. Can easily keep track of interruptions and resets during data writing and erasing, and can easily grasp data writing and erasing states even after power is turned off. There is an effect that it is possible to provide a data management method using a flash memory which is suitable for the above.

Further, by providing a data management area for storing the use state of the data area in the block, the state of the data area need only be searched for in the data management area. Not
This has the effect of providing a data management method using a flash memory which can grasp the state of the data area and can easily detect required data.

Further, by regularly arranging the data area and the data management table, the head address of the data area can be easily calculated from the address of the data management table, so that the time required for reading necessary data can be shortened. The size of the data area can be easily calculated from the address of the data management table, and only needs to be the size of the data storage area (for example, 16 bytes), and a flash memory suitable for a portable electronic device such as a mobile phone is used. There is an effect that a data management method can be provided.

Further, there is an effect that a data management method using a flash memory which can easily cope with a difference in the capacity of a block in the flash memory can be provided.

Further, since data stored in the conventional EEPROM can be taken into the flash memory, the EEPROM is used.
Can be deleted, and there is an effect that it is possible to provide a data management method using a flash memory capable of realizing downsizing when applied to a portable electronic device such as a mobile phone.

In the above embodiment, the case where the data management table 20 and the table in the block management area 3 are 16 bits has been described. However, when the access unit of the flash memory is 8 bits, each table has 8 bits. The same effect can be obtained by configuring with bits.

The data management table 80 when the access unit is 8 bits, the current block use / non-use table 81,
FIG. 11 shows an example of the erase status table 82 of the block n. The same applies to other access units.
In the above embodiment, the case where the data area size of the data storage area 5 is 16 bits has been described. However, the data length may be any size as long as it is within one block size of the flash memory and within the data storage area 5.

In the above embodiment, the case where the management flag and the data number are stored in the data management table 20 has been described. However, the management flag and the data number are separated, and an area for storing only the data number is provided separately. A similar effect can be obtained by the management method, and there is an effect that the data number that can be managed can be expanded.

In the above-described embodiment, the case where the number of blocks for storing data is three has been described. However, the same effect can be obtained if the number of blocks is two or more. Further, the configuration in one block can also be used in a data management method when one block stores data.

Further, in the above-described embodiment, the case has been described where each of the data management table 20 and each table in the block management area 3 is configured by a flag in units of bits. Can be obtained. FIG. 12 shows an example in which the data management table 20, the data management table 80 in the block management area 3, the current block use / non-use table 81, and the erasure status table 82 of the block n are configured in byte units.

In the above embodiment, the case where one block in the flash memory 12 is constituted by the block management area 3, the data management area 4, and the data storage area 5 has been described. The same effect can be obtained even if the configuration is such that the block management area 3, the data management area 4, and the data storage area 5 are provided in one block and this one block is used in rotation.

In the above-described embodiment, the data management method for coexisting the program and data in the flash memory 12 has been described. However, the present invention can be used as a data management method when only data is stored in the flash memory 12.

In the above-described embodiment, the case where the flash memory is used as the program rewritable memory has been described. However, the data unit of “write” and “read” is byte or word, and the unit to be erased is divided by the memory. The same effect can be obtained in the memory of the block unit.

Further, in the above embodiment, the description has been given of the case of the flash memory having the initial value of “1” due to the configuration of the storage element. Even in this case, the same effect can be obtained by setting the value to be written in each table of the data management table 20 and the block management area 3 to "1" (the inverted value of "0" written when the initial value is "1"). Can be done.

In the above embodiment, the case where the SRAM is used as the RAM 13 has been described.
There is no limitation as long as it is a common memory that can read and write.

[0062]

As described above, according to the present invention, the start / end of data writing to the data storage area and the data storage in the data storage area are "present".
Indicating the validity / invalidity of the stored data as to whether the data is stored or not stored, information on the type of data, and a data area effective for storing the data for each block set in the use / non-use table The information on the presence / absence of the presence / absence of the data and the information on the erasure status such as the start / end of the “erase” of the data for each block set in the erasure status table at power-off. However, the data that needs to be retained is managed and stored in the data storage area of a block that is an erase unit of the flash memory, and rewriting using the data storage area in the block or the data storage area of a plurality of blocks is performed. Erasure processing to the initial state accompanying data “rewrite” in flash memory Since eliminating the need to perform at "rewriting" of the data, it is possible to shorten the time required to "rewrite" of the data in the flash memory, can avoid the restrictions on the reading of the data for each rewriting of the data is generated,
Also, by leaving the status of “write” and “erase” of data, it is possible to easily confirm the completion of erasure and the like even after power interruption during data writing and erasure or interruption of processing due to reset occurrence. There is an effect that data that must be retained even in the state can be stored in the flash memory with high reliability.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a mobile phone to which a data management method according to an embodiment of the present invention is applied.

FIG. 2 is an explanatory diagram showing a configuration of a flash memory in a mobile phone to which the data management method according to the embodiment of the present invention is applied;

FIG. 3 is an explanatory diagram showing a configuration of a data management table in a mobile phone to which the data management method according to the embodiment of the present invention is applied.

FIG. 4 is an explanatory diagram showing a block management area in a mobile phone to which the data management method according to the embodiment of the present invention is applied.

FIG. 5 is an explanatory diagram showing a current block use presence / absence table in the mobile phone to which the data management method according to the embodiment of the present invention is applied;

FIG. 6 is an explanatory diagram showing a block erasure status table in a mobile phone to which the data management method according to the embodiment of the present invention has been applied.

FIG. 7 is a flowchart showing an operation at the time of writing data by the data management method according to the embodiment of the present invention.

FIG. 8 is a flowchart showing an operation when data is erased by the data management method according to the embodiment of the present invention.

FIG. 9 is a flowchart showing an operation at the time of writing data by the data management method according to the embodiment of the present invention.

FIG. 10 is a flowchart showing an operation when data is erased by the data management method according to the embodiment of the present invention.

FIG. 11 is an explanatory diagram showing an example of a data management table, a current block use presence / absence table, and a block n erasure status table when one access unit is 8 bits according to a data management method of another embodiment of the present invention. .

FIG. 12 is an explanatory diagram showing an example of a case where a data management table, a current block use / non-use table, and an erasure status table of a block n are configured in byte units according to a data management method of another embodiment of the present invention.

[Explanation of symbols]

2 Data storage block, 3, 30 Block management area, 4 Data management area, 5 Data storage area, 12 Flash memory, 20 Data management table, 31 Use of current block Table (use table) 32... Block erase status table (erase status table).

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[Procedure amendment]

[Submission date] March 27, 2000 (2003.
7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a data management method using a flash memory, and more particularly, to a data management method using a flash memory capable of efficiently performing a data rewriting process.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

Accordingly, an object of the present invention is to solve the first, second, and third problems, thereby reducing the time required for data rewrite processing, and enabling the rewrite processing to be performed efficiently. An object of the present invention is to provide a data management method using a flash memory.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

[0008]

A data management method using a flash memory according to the present invention has a data storage area for storing data which needs to be held even when the power is turned off in a data unit of a data area size. A data storage block is secured in a block which is an erase unit of the flash memory, and information indicating the state of the data storage area for each data storage area set in the block and stored in the data storage area. The data is managed by the information of the data and information indicating the states of the own block and the other blocks for each of the blocks, and an erasing process to an initial state at the time of “rewriting” of the data is omitted. .

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

In a data management method using a flash memory according to the present invention, a data storage block having a data storage area for storing data which is required to be held even in a power-off state where a data unit is a data area size is stored in a flash memory. Information indicating the state of the data storage area for each of the data storage areas and information of the data stored in the data storage area, which is set in each block as an erase unit of the block; Using the information indicating the states of the own block and the other blocks for each data, data management is performed to eliminate the need for the data erasing process accompanying the data rewriting, and the time required for the data rewriting in the flash memory And the efficiency of the data rewriting process is improved.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction contents]

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below. The data management method using the flash memory according to the present embodiment is suitable for application to a program rewritable memory, particularly to a portable electronic device having a flash memory, and performs a data rewriting process efficiently. Reducing restrictions on the operation of the program that occurs when a program and data that must be retained even without power supply are stored in the same flash memory, and when applied to a portable electronic device, An EEPROM required to retain data can be deleted, thereby realizing a small and lightweight portable electronic device.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0062

[Correction method] Change

[Correction contents]

[0062]

As described above, according to the present invention, a data storage block having a data storage area for storing data that needs to be held even in a power-off state where the data unit is a data area size is a flash memory. Information indicating the state of the data storage area for each of the data storage areas and information of the data stored in the data storage area, which is set in each block as an erase unit of the block; The data is managed by the information indicating the state of the own block and the other block for each data, so that it is not necessary to perform the erasing process to the initial state accompanying the "rewriting" of the data in the flash memory at the time of "rewriting" of the data. Therefore, the time required for rewriting data in the flash memory can be reduced, and the data There is an effect that can be efficiently performed the rearrangement process can.

Claims (5)

[Claims] 1. A data storage block having a data storage area for storing data that needs to be held even in a power-off state where a data unit is a data area size is secured in a block that is an erase unit of a flash memory. The data is managed by information indicating the state of the data storage area for each data storage area, information of the data stored in the data storage area, and information indicating the states of the own block and other blocks for each block. A data management method using a flash memory. 2. The information indicating the state of the data storage area and the information of data stored in the data storage area are stored in a data management table corresponding to each of the data storage areas. Information indicating the start / end of writing, whether data is stored “present” or “not present” in the data storage area, indicating whether the stored data is valid / invalid, and information about the type of data; The information indicating the status of the own block and the other blocks for each block is used for whether or not there is a valid data area for storing the data for each block set in the use / non-use table for each block. Information on the presence or absence of the data for each block set in the erase status table for each block. 2. The information according to claim 1, wherein the information is an erasure status regarding the start / end of the "erasure".
A data management method using the flash memory described above. 3. The data management table, the use presence / absence table, and the erasure status table, each information is set in a bit unit of one data unit size of the flash memory. Data management method using flash memory. 4. Data is stored in a data storage area, information indicating data storage “present” and information indicating a type of the data are stored in a corresponding data management table, and stored in a data storage area in which old data exists. The corresponding data management table is rewritten by overwriting information indicating "no data storage" in the corresponding data management table, and the erasing process to the initial state accompanying the "rewriting" of the data in the flash memory is performed by the " 4. The data management method using a flash memory according to claim 2 or 3, wherein the method does not need to be performed at the time of "rewriting." 5. A method according to claim 1, wherein a plurality of blocks for storing data are used in rotation based on information on the use or non-use of each block set in a use / non-use table, and whether a block having an effective data storage area is used. Information indicating that the block is valid is written in the table, and when a valid block is changed to an erasable block, information indicating that the block is erasable is overwritten in the use / non-use table of the block. Then, the data is "rewritten" using a plurality of blocks which are the erasing units of the flash memory, and an erasing process to the initial state accompanying the "rewriting" of the data in the flash memory is performed at the time of "rewriting" the data. 4. A data management method using a flash memory according to claim 2, wherein the data management method eliminates the need. .