JPH04123243A - Data writing device - Google Patents

Abstract

PURPOSE:To extend memory using life and to effectively utilize a memory resource by providing this data writing device with a deciding means for deciding the using life of the memory and an address changing means for setting up a new write address in write data by referring the stored contents of a write address control means. CONSTITUTION:The data writing device is provided with the deciding means 4 for checking whether data written in the memory 1 have normally been written or not and the address changing means 5 for setting up a new write address in write data by referring the stored contents of the write address control means 2. When the limit of the using life is decided, a new write address out of excessive capacity is set up in the write data by referring the stored contents of the means 2. Thereby, data to be frequently written are stored in another area. Thus, the memory using life can be extended and the memory resource can be effectively utilized.

Description

[Detailed description of the invention] [Purpose of the invention] [Industrial application field] The present invention allows data to be rewritten. It relates to data writing devices such as EEPROM.

[Conventional technology]

EEFROM is well known as a nonvolatile memory in which stored information can be electrically erased and rewritten. Various types of data are written to this type of memory, but in conventional data writing, a fixed address was set for each piece of data, and when the data content was changed, it was written to that fixed address. .

By the way, the number of times that data can be rewritten in an EEPROM is limited to approximately 10,000 times. If the rewriting limit is exceeded, the memory function will be significantly degraded, resulting in inconveniences such as the inability to store data normally.

On the other hand, depending on the application, it may be necessary to repeatedly write only specific data, and in such cases, the number of rewrites to a specific address increases, so the lifespan of a specific area will end sooner than other areas. There is a possibility that such a situation may occur. Further, there are cases where a specific area is repeatedly written due to malfunction, and even in such a case, only the specific area reaches the end of its life sooner.

However, if a specific area reaches the end of its lifespan quickly, the data assigned to that area's address cannot be stored accurately, so the entire memory had to be discarded even if other areas were usable. .

[Problem to be solved by the invention]

Therefore, as mentioned above, with conventional rewritable memory such as EEPROM, there is a possibility that the number of rewrites in some areas will suddenly increase, and it is necessary to shorten the memory life and make effective use of memory resources. There was a problem with it becoming unusable.

The present invention has been made in view of the above-mentioned circumstances, and provides a data writing device that can extend the memory life by averaging the number of data rewrites in the entire memory, and can effectively utilize memory resources. The purpose is to

[Structure of the Invention] [Means for Solving the Problems] In order to achieve the above object, the pig writing device according to the present invention is capable of rewriting data multiple times, and is capable of rewriting data more than once. A memory having a large capacity, a write address management means in which a storage address of data stored in the memory and an area whose life has expired in the memory are stored, and writing based on the storage contents of the write address management means. data writing means for writing data to a predetermined address of the memory, and checking whether the data written by the data writing means to the predetermined address of the memory has been written normally; a determination means for determining the lifespan; and when the determination means determines that the write area has reached its lifespan, a new write address is determined for the write data by referring to the memory contents of the write address management means; and address changing means for setting the address.

[Effect]

According to the present invention, when data is written to a predetermined address, it is checked whether the data has been written normally or not, and it is determined whether the area has reached the end of its lifespan. If it is determined that the service life has come to an end, a new write address is set for the write data from among the remaining capacity by referring to the storage contents of the address management means. Therefore, for example, data that is frequently written 1q is stored in a separate area, so memory resources can be used effectively, and as a result,
Extends lifespan.

〔Example〕

Examples of the present invention will be described below.

FIG. 1 is a diagram showing functional blocks of a data writing device according to an embodiment of the present invention. In this embodiment, an EEPROM (hereinafter referred to as "memory") 1 having a capacity of several bytes of full data A times the total data capacity to be written, and a storage address and a memory of data stored in this memory 1 are used. A write address management means 2 in which an area whose life has reached the end of its life is stored, and a memory 1
a data writing means 3 for writing predetermined data to a predetermined address in the memory 1; a determining means 4 for checking whether the data written to the memory 1 has been written normally; An address change stage 5 for setting a new write address for the write data by referring to the storage contents of the write address management means 2 when it is determined that the service life has expired.

Memory 1 has, for each data item, A data areas (data size bytes) in which the data is stored, and a management data area (1 byte) in which information such as the number of data areas in which the data is currently stored is stored. ) are provided for each. The addresses of this data area and management data area are stored in the address management means 2 for each data,
It is updated by input from the address changing means 5.

Next, the operation of this embodiment configured as above will be explained with reference to FIGS. 2 to 4.

When the power is turned on, the initialization routine shown in FIG.
CN T) to O゛. Next, each time write data is input to the writing means 3, a write routine shown in FIG. 3 is executed. That is, the writing means 3 refers to the address management means 2 to obtain the addresses of the data area and management data area of the data requested to be written, and writes the respective data to the addresses (step Sl). Then, after a predetermined period of time has elapsed since the writing, for example, 10 m5 has passed (step S2), the data is read from the memory 1 into the determination means 4 (step S3), and is read as the data requested to be written. It is determined whether or not the data are equal to each other (step S4). As a result of the determination, if they are equal, the writing process is ended. Also, if the data area has reached the end of its lifespan,
Since they are not written correctly, they do not become equal in step S4. Therefore, the address changing means 5 determines which data area is currently being used among the A data areas prepared from the data in the management data area (step S5).
), if all A are not used up yet, set the area with l data size shift as a new data area, transmit the address to the address management means 2 and the writing means 3, and rewrite the contents of the management data area ( Step S6),
Further, the above data is written to the newly set data area and management data area (step S7).

Note that in step 5, if all A areas have already reached the end of their lifespan, an error message is displayed (step S8).

Further, when referring to the written data, a reference routine shown in FIG. 4 is executed.

According to this embodiment, a capacity of A times the data size → -1 byte is provided for each piece of data, and the currently used data area is managed in the 1-byte management data area. Therefore, data areas that are frequently rewritten and reach the end of their lifespan quickly are switched to other data areas, so that they can be used until all memory resources are used up, making effective use of memory resources and eliminating the need for traditional usage methods. The lifespan of memory can be significantly extended.

Next, other embodiments of the present invention will be described.

In this embodiment, the basic functional block configuration is the same as that shown in FIG. 1, but the configuration of the memory consisting of EEPROM is different. The memory used in this embodiment is roughly divided into two areas, one being a data area for storing degoters, and the other being an address storage area for storing addresses of each data. The address storage area has a capacity of (total number of data x 3 + 2) bytes, and consists of a 3-byte address area provided for each data and a 2-byte additional area. In the 3-byte address area allocated for each piece of data, 2 bytes store the storage address of the current data, and the remaining 1 byte stores the data size. Further, the additional area stores as an initial value the address that becomes the start when the area corresponding to the size of each data is removed sequentially from the start address of the data area. Further, it is assumed that the data area has a capacity that is sufficiently larger than the total data size, and is used in order from the first address.

Next, the operation of this embodiment will be explained with reference to FIGS. 5 to 7.

First, by the initialization routine shown in FIG.
The data area and address storage area are initialized. Next, the write routine shown in FIG. 6 is executed to write data. In other words, the data requested to be written is
The data is written to the address stored in the address area (step TI). And after writing,
For example, if 10 m5 have passed (step T2), the data is read from the memory 1 into the determining means 4 (step T2).
3) It is determined whether the data requested to be written and the read data are equal (step T4). As a result of the determination, if they are equal, the writing process is ended. If they are not equal, the start address of the data is changed to the address stored in the additional area, and the address shifted by the data size from this address is set as the final address (step T5). Data is written anew to the address changed in this way (step T6). Then, the address is updated to either the address stored in the additional area or an address shifted by the data size requested for writing.

Further, when referring to the written data, a reference routine shown in FIG. 7 is executed.

As described above, according to this embodiment, the start address of the writable data area and the size of each data are managed, and when a certain area reaches the end of its lifespan, the data is transferred to the start address of the writable data area. Since the data is filled in sequentially starting from the address and the first address is updated according to the data size, it is possible to use memory resources effectively, similar to the above embodiment, and compared to the conventional method of using memory, Lifespan can be significantly extended.

[Effects of the Invention] As described in detail above, the present invention provides a data writing device that can extend the memory life by averaging the number of data rewrites in the entire memory, and can effectively utilize memory resources. Can be provided.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram of a data writing device according to an embodiment of the present invention, FIG. 2 is a diagram showing an initialization routine of the embodiment, and FIG. 3 is a diagram illustrating an initialization routine of the embodiment. , FIG. 6 is a diagram showing the write routine of the embodiment at the same place, and FIG. 7 is a diagram showing the reference routine of the embodiment at the same place. 1...EEPROM, 2...Address management means, 3.
Data writing means, 4. Judgment means, 5. Address changing means.

Claims (1)

[Scope of Claims] A memory that allows data to be rewritten multiple times and has a capacity sufficiently larger than the amount of data to be written, and a storage address of the data stored in the memory and a lifespan in the memory. a write address management means in which an area stored in the memory is stored; a data write means for writing write data to a predetermined address of the memory based on the storage contents of the write address management means; determining means for determining the lifespan of the data writing area by checking whether data written to a predetermined address of the data writing area has been written normally; A data writing device comprising: address changing means for setting a new write address for the write data by referring to the storage contents of the write address management means when the write address has been written.