JP2019045951A - Vehicle information memory device - Google Patents

Abstract

To provide a vehicle information memory device capable of securing reliability of stored data while reducing the use capacity of a non-volatile memory.SOLUTION: In a vehicle failure diagnosis system 10, a memory control unit 28 of an engine ECU 12 writes the number of rewrites Nr1 read from a first number storage area 30n in a volatile memory 26 before starting an update of a first information storage area 30v, and writes an unused value not used for counting the number of rewrites Nr1 in the first number storage area 30n. The memory control unit 28 performs memory control to count and update the number of rewrites Nr1 read from the volatile memory 26 after the update of the first information storage area 30v is completed and to write the same in the first number storage area 30n.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle information storage device mounted on a vehicle and storing vehicle information indicating the state of the vehicle.

  BACKGROUND Conventionally, a vehicle information storage device mounted on a vehicle and storing vehicle information indicating the state of the vehicle is known. For example, various techniques have been proposed for improving the reliability of failure diagnosis information sequentially stored in a non-volatile memory with respect to a vehicle self-diagnosis function (OBD; On-Board Diagnostics).

  Patent Document 1 proposes an apparatus for determining an abnormality related to the storage state of a non-volatile memory by storing the same failure code (DTC; Diagnostic Trouble Code) in three storage areas and taking majority of data. ing.

Patent 4475320 gazette

  Recently, engine ECUs (Electronic Control Units) compatible with the OBD 2 are becoming widespread. The ECU simultaneously stores not only the failure code but also freeze frame data at the moment when the failure code is generated.

  However, in the device proposed in Patent Document 1, since it is necessary to always prepare three sets of storage areas for majority, the use capacity of nonvolatile memory is increased by 50% as compared with the case of two sets. It will This problem is noticeable because this used capacity is roughly proportional to the size of freeze frame data.

  The present invention has been made to solve the above-described problems, and it is an object of the present invention to provide a vehicle information storage device capable of securing the reliability of stored data while reducing the used capacity of the nonvolatile memory.

  A vehicle information storage device according to the present invention is a device mounted on a vehicle and storing vehicle information indicating a state of the vehicle, the non-volatile memory having a first storage area and a second storage area, and A volatile memory storing at least the number of times of rewriting of vehicle information, and a storage control unit performing storage control for the non-volatile memory and the volatile memory, the first storage area stores the vehicle information A first information storage area and a first number storage area in which the number of rewrites is stored, the second storage area stores a second information storage area in which the vehicle information is stored, and the number of rewrites is stored And the storage control unit is configured to store the number of rewrites read from the first number storage area before starting the update of the first information storage area to the volatile memory. writing And writing a nonuse value not used for counting the number of rewrites in the first number storage area, counting and updating the number of rewrites read from the volatile memory after updating of the first information storage area is completed And performing storage control of writing in the first number storage area, and writing the number of rewrites read from the second number storage area in the volatile memory before starting updating the second information storage area; And writing a nonuse value not used for counting the number of rewrites in the second number storage area, counting and updating the number of rewrites read from the volatile memory after updating of the second information storage area is completed And performs storage control to write in the second number storage area.

  By configuring in this way, for example, even when the information temporarily stored in the volatile memory is lost due to a momentary power loss, the numerical relationship between the number of times of rewriting currently stored (a single value Alternatively, the update status of the first storage area and the second storage area can be determined based on the relative value), and the stored data can be properly recovered by performing the necessary measures thereafter. Thereby, the reliability of stored data can be ensured while reducing the used capacity of the nonvolatile memory.

  In the storage control unit, the number of rewrites stored in the first number storage area is the nonuse value, and the number of rewrites stored in the second number storage area is the nonuse value If not, the number of rewrites in the second number storage area is copied and written in the first number storage area, and the vehicle information in the second information storage area is copied and written in the first information storage area The control is performed, and the number of rewrites stored in the first number storage area is not the nonuse value, and the number of rewrites stored in the second number storage area is the nonuse value. A storage control is performed in which the number of times of rewriting of the first number storage area is copied and written in the second number storage area, and the vehicle information of the first information storage area is copied and written in the second information storage area It is also good.

  As a result, in a state in which one of the storage areas whose number of rewrites is an unused value is being updated, the number of rewrites and the vehicle information can be copied from the other storage area to restore the latest storage state.

  Further, the storage control unit is configured to, when the number of rewrites stored in the first number storage area is larger than the number of rewrites stored in the second number storage area, the vehicle of the first information storage area Storage control is performed to copy information and write in the second information storage area, and the number of rewrites stored in the first number storage area is smaller than the number of rewrites stored in the second number storage area The storage control may be performed to copy the vehicle information in the second information storage area and write it in the first information storage area.

  As a result, in a state in which one storage area having a large number of rewrites is updated and the other storage area is before update, the vehicle information is copied from one storage area to shift to the latest storage state. be able to.

  Further, the storage control unit may not write to the first storage area and the second storage area other than the copy until the storage control for copying the vehicle information is completed. By prohibiting writing other than duplication during recovery of stored data, it is possible to prevent occurrence of an abnormality relating to the storage state.

  Further, the vehicle information storage device may stop the supply of power in response to the turning-off operation of the ignition switch of the vehicle. Vehicles that do not have a self-shutdown function after the engine is turned off are particularly effective because they can not obtain volatile memory data backup.

  According to the vehicle information storage device of the present invention, it is possible to secure the reliability of stored data while reducing the used capacity of the non-volatile memory.

BRIEF DESCRIPTION OF THE DRAWINGS It is a whole block diagram of the vehicle failure diagnostic system incorporating the vehicle information storage apparatus in one Embodiment of this invention. It is a transition diagram regarding the storage state of the non-volatile memory shown in FIG. 1, and volatile memory. It is a figure which shows typically the characteristic of the storage control in each area.

  Hereinafter, preferred embodiments of a vehicle information storage device according to the present invention will be described and described with reference to the accompanying drawings.

[Configuration of Vehicle Failure Diagnosis System 10]
FIG. 1 is an overall configuration diagram of a vehicle failure diagnosis system 10 in which a vehicle information storage device according to an embodiment of the present invention is incorporated. The vehicle failure diagnosis system 10 is a system mounted on a vehicle (for example, a two-wheeled vehicle or a four-wheeled vehicle) not shown and having a self-diagnosis function of the vehicle. The vehicle failure diagnosis system 10 includes an engine ECU 12 as a vehicle information storage device, a sensor group 14, an engine 16, and a power supply 18.

  The sensor group 14 includes one or more sensors capable of detecting the state of the vehicle. Examples of the sensor include a water temperature sensor, an oil temperature sensor, a vehicle speed sensor, a crank angle sensor, an intake pressure sensor, an atmospheric pressure sensor, a throttle opening sensor, and an O 2 sensor.

  The power supply 18 supplies power to each part of the vehicle (including the engine ECU 12). Here, the power supply 18 supplies power to the engine ECU 12 or stops the supply thereof in conjunction with on / off of the ignition switch 20.

  The engine ECU 12 performs operation control of the engine 16 which is a drive source of the vehicle, and acquires and stores information indicating the state of the vehicle (hereinafter, vehicle information) as needed. Specifically, the engine ECU 12 is configured to include an arithmetic processing unit 22, a non-volatile memory 24, and a volatile memory 26.

  The arithmetic processing unit 22 includes, for example, a central processing unit (CPU) or a micro-processing unit (MPU). The arithmetic processing unit 22 functions as a storage control unit 28 which performs storage control on the nonvolatile memory 24 and the volatile memory 26 by reading and executing a program from a ROM (Read Only Memory) not shown.

  The non-volatile memory 24 is a memory capable of holding stored data without supplying power, and is constituted of, for example, an EEPROM (Electrically Erasable Programmable Read-Only Memory) and a flash memory. The nonvolatile memory 24 has two storage areas (hereinafter, the first storage area 30 and the second storage area 32) having the same area size.

  The first storage area 30 includes a first count storage area 30n in which one rewrite count Nr1 is stored, and a first information storage area 30v in which M sets (M ≧ 1) of vehicle information Iv1 are stored. . The second storage area 32 includes a second count storage area 32n in which one rewrite count Nr2 is stored, and a second information storage area 32v in which M sets (M ≧ 1) of vehicle information Iv2 are stored. .

  The number of rewrites Nr1 is the number of successful rewrites of the first storage area 30 (update of the vehicle information Iv1), and the number of rewrites Nr2 is the number of successful rewrites of the second storage area 32 (update of the vehicle information Iv2). is there. The vehicle information Iv1 and Iv2 correspond to, for example, information of one set of failure code (DTC) and freeze frame data (time series of sensor values).

  The volatile memory 26 is a memory that can hold stored data only when power is supplied, and is configured of, for example, a dynamic random access memory (DRAM) or a static random access memory (SRAM). The volatile memory 26 has a storage area 34 in which information necessary for storage control (specifically, the first rewrite frequency A, the second rewrite frequency B, and the latest vehicle information Iv) is temporarily stored.

[Operation of engine ECU 12]
The engine ECU 12 as a vehicle information storage device is configured as described above. Subsequently, the operation of the engine ECU 12 (in particular, the storage control unit 28) will be described in detail with reference to FIGS. 2 and 3.

  FIG. 2 is a transition diagram related to storage states of the non-volatile memory 24 and the volatile memory 26 shown in FIG. More specifically, this figure shows the stepwise change of the stored values in the first storage area 30, the second storage area 32, and the storage area 34 at each of the processing steps S0 to S10. In addition, the part (storage area) where the stored value was updated is described by the thick rectangular frame.

  Step S0 corresponds to the storage state in which the fifth rewrite is normally performed. In this case, the number of times of rewriting Nr1 (= 5) of the first storage area 30 is equal to the number of times of rewriting Nr2 (= 5) of the second storage area 32. Further, all the vehicle information Iv1 of the first storage area 30 matches the vehicle information Iv2 of the second storage area 32. Note that the value “NULL” is stored in the storage area 34 by the initialization operation of the storage control unit 28.

  In step S1, the storage control unit 28 performs control to temporarily store the latest vehicle information Iv by writing the latest vehicle information (hereinafter referred to as the latest vehicle information Iv) from the sensor group 14 in the volatile memory 26. . As a result, the stored value (latest vehicle information Iv) of the storage area 34 is updated from "NULL" to "sixth information".

  In step S2, the storage control unit 28 temporarily stores the latest vehicle information Iv by reading out the number of rewrites Nr1 of the first storage area 30 from the non-volatile memory 24 and writing it in the storage area 34 of the volatile memory 26. Take control. As a result, the stored value (first rewrite count A) of the storage area 34 is updated from “NULL” to “5”.

  In step S3, the storage control unit 28 updates the number of rewrites Nr1 of the first storage area 30 (specifically, the first number storage area 30n) to a value not used for counting (hereinafter referred to as an unused value). Take control. This non-use value may be an arbitrary value (specifically, a value larger than the upper limit value) deviating from the operation range of the number of times of rewriting Nr1 including, for example, 0.

  As described above, the storage control unit 28 writes the number of rewrites Nr1 read from the first number of storage areas 30n to the volatile memory 26 before starting the update of the first information storage area 30v, and the number of rewrites Nr1. Storage control is performed to write an unused value not used for counting in the first count storage area 30n (steps S2 and S3).

  In step S4, the storage control unit 28 performs control to read out the temporarily stored latest vehicle information Iv from the volatile memory 26 and write it in the first storage area 30 of the non-volatile memory 24. As a result, the storage value (vehicle information Iv1) of the first information storage area 30v is updated from the "fifth information" to the "sixth information".

  In step S5, the storage control unit 28 reads the temporarily stored first rewriting number A from the volatile memory 26, updates the count (A (A + 1), and then stores it in the first storage area 30 of the non-volatile memory 24. Control writing. As a result, the stored value (number of rewrites Nr1) of the first number storage area 30n is updated from "0" to "6".

  As described above, the storage control unit 28 performs storage control to count and update the number of rewrites Nr1 read from the volatile memory 26 after the update of the first information storage area 30v is completed, and to write the same to the first count storage area 30n. (Steps S4 and S5).

  In step S6, the storage control unit 28 controls the temporary storage of the number of rewrites Nr2 by reading the number of rewrites Nr2 of the second storage area 32 from the non-volatile memory 24 and writing it in the storage area 34 of the volatile memory 26. I do. As a result, the stored value (second rewrite count B) of the storage area 34 is updated from “NULL” to “5”.

  In step S7, the storage control unit 28 performs control to update the number of rewrites Nr2 stored in the second storage area 32 (specifically, the second number storage area 32n) to the nonuse value (0). Here, the non-use value of the number of times of rewriting Nr2 may be the same as or different from the non-use value of the number of times of rewriting Nr1.

  As described above, the storage control unit 28 writes the number of rewrites Nr2 read from the second number of storage areas 32n to the volatile memory 26 before starting the update of the second information storage area 32v, and the number of rewrites Nr2 Storage control is performed to write an unused value not used for counting in the second count storage area 32n (steps S6 and S7).

  In step S <b> 8, the storage control unit 28 performs control of reading the temporarily stored latest vehicle information Iv from the volatile memory 26 and writing the latest vehicle information Iv in the second storage area 32 of the non-volatile memory 24. Thereby, the stored value (vehicle information Iv2) of the second information storage area 32v is updated from the "fifth information" to the "sixth information".

  In step S9, the storage control unit 28 reads the temporarily stored second rewrite count B from the volatile memory 26, updates the count (B B B + 1), and then stores it in the second storage area 32 of the non-volatile memory 24. Control writing. Thereby, the stored value (number of rewrites Nr2) of the second number storage area 32n is updated from "0" to "6".

  As described above, the storage control unit 28 performs storage control to count and update the number of rewrites Nr2 read from the volatile memory 26 after the update of the second information storage area 32v is completed, and to write the same to the second count storage area 32n. (Steps S8 and S9).

  Step S10 corresponds to the storage state in which the sixth rewriting is normally performed. The value “NULL” is stored in the storage area 34 by the initialization operation of the storage control unit 28. Here, the number of times of rewriting Nr1 (= 6) of the first storage area 30 is equal to the number of times of rewriting Nr2 (= 6) of the second storage area 32. Further, all the vehicle information Iv1 of the first storage area 30 matches the vehicle information Iv2 of the second storage area 32.

  FIG. 3 is a diagram schematically showing the features of storage control in each section. More specifically, this figure shows the behavior (events and results) of storage control for each processing timing when the state check processing is performed.

  Here, the "state check" is a process of confirming the storage state of the non-volatile memory 24, and specifically means to confirm whether the number of rewrites Nr1 and the number of rewrites Nr2 match. . The processing phases are classified into ten sections (first to tenth sections) shown in FIG.

  The storage control unit 28 may periodically or periodically execute the state check process. As an irregular example, [1] when reading out the nonvolatile memory 24, [2] immediately after the on operation of the ignition switch 20, or [3] a predetermined time has elapsed from the end of the series of operations shown in FIG. When is mentioned.

  In the first to third sections, the number of rewrites Nr1 and Nr2 are equal to one another (Nr1 = Nr2 = 5). In this case, the storage control unit 28 determines that both of the vehicle information Iv1 and Iv2 are latest, and does not perform special processing on the non-volatile memory 24. That is, the non-volatile memory 24 maintains the state (the state where data synchronization is maintained) in which the fifth vehicle information Iv1 and Iv2 are stored.

  In the fourth and fifth sections, the number of rewrites Nr1 stored in the first number storage area 30n is an unused value (that is, Nr1 = 0), and the number of rewrites Nr2 stored in the second number storage area 32n is It is not an unused value (Nr2 = 5). In this case, the storage control unit 28 determines that only the vehicle information Iv2 is the latest.

  That is, in a state where one storage area (first storage area 30) whose number of rewrites Nr1 is an unused value is being updated, the number of rewrites Nr2 and vehicle information Iv2 are updated from the other storage area (second storage area 32). It is possible to return to the latest memory state by duplicating.

  In this case, the storage control unit 28 duplicates the rewrite count Nr2 of the [1] (Nr1 1 Nr2) second count storage area 32n and writes it in the first count storage area 30n, as well as [2] (Iv1 I Iv2) The storage control is performed to copy the vehicle information Iv2 of the 2 information storage area 32v and write it in the first information storage area 30v. As a result, the non-volatile memory 24 returns to the state in which the fifth vehicle information Iv1 and Iv2 are stored (that is, the state in which data synchronization is maintained).

  Here, the storage control unit 28 does not write in the first storage area 30 and the second storage area 32 other than this duplication until the storage control for copying the vehicle information Iv2 is completed. By prohibiting writing other than duplication during recovery of stored data, it is possible to prevent occurrence of an abnormality relating to the storage state.

  In the sixth and seventh sections, the number of rewrites Nr1 (= 6) and Nr2 (= 5) are not unused values, and satisfy the magnitude relationship of Nr1> Nr2. In this case, the storage control unit 28 determines that only the vehicle information Iv1 is the latest.

  That is, in a state in which one storage area (first storage area 30) having a large number of rewrites Nr1 is updated and the other storage area (second storage area 32) is not updated, the first storage area 30 is It is possible to shift to the latest memory state by duplicating the vehicle information Iv1.

  In this case, the storage control unit 28 duplicates the rewrite count Nr1 of the [1] (Nr2 2 Nr1) first count storage area 30n and writes it in the second count storage area 32n, while the [2] (Iv2 I Iv1) first Storage control is performed to copy the vehicle information Iv1 of the first information storage area 30v and write it in the second information storage area 32v. Note that, instead of copying the number of times of rewriting Nr1, the number of times of rewriting Nr2 that has been updated may be written in the second number storing area 32n.

  As in the case of the fourth and fifth sections, the storage control unit 28 sends the first storage area 30 and the second storage area 32 other than this copy until the storage control for copying the vehicle information Iv1 is completed. Do not write As a result, the non-volatile memory 24 is in a state of storing the sixth vehicle information Iv1 and Iv2 (that is, a state in which data synchronization is maintained).

  In the eighth and ninth sections, the number of rewrites Nr1 stored in the first count storage area 30n is not the unused value (Nr1 = 6), and the number of rewrites Nr2 stored in the second count storage area 32n is the unused value (That is, Nr2 = 0). In this case, the storage control unit 28 determines that only the vehicle information Iv1 is the latest.

  That is, in a state where one storage area (second storage area 32) in which the number of rewrites Nr2 is an unused value is being updated, the number of rewrites Nr1 and vehicle information Iv1 from the other storage area (first storage area 30) By copying, it is possible to shift to the latest memory state.

  In this case, the storage control unit 28 duplicates the rewrite count Nr1 of the [1] (Nr2 2 Nr1) first count storage area 30n and writes it in the second count storage area 32n, while the [2] (Iv2 I Iv1) first Storage control is performed to copy the vehicle information Iv1 of the first information storage area 30v and write it in the second information storage area 32v.

  As in the case of the sixth and seventh sections, the storage control unit 28 sends the first storage area 30 and the second storage area 32 other than this copy until the storage control for copying the vehicle information Iv1 is completed. Do not write As a result, the non-volatile memory 24 is in a state of storing the sixth vehicle information Iv1 and Iv2 (that is, a state in which data synchronization is maintained).

  In the tenth section, the number of rewrites Nr1 and Nr2 are equal to one another (Nr1 = Nr2 = 6). In this case, the storage control unit 28 determines that both of the vehicle information Iv1 and Iv2 are latest, and does not perform special processing on the non-volatile memory 24. That is, the non-volatile memory 24 maintains the state in which the sixth vehicle information Iv1 and Iv2 are stored (the state in which data synchronization is maintained).

[Effect by engine ECU 12 (vehicle information storage device)]
As described above, the engine ECU 12 is mounted on a vehicle and stores vehicle information Iv1 and Iv2 indicating the state of the vehicle, and [1] a non-volatile memory 24 having a first storage area 30 and a second storage area 32. And [2] volatile memory 26 which stores at least the number of times of rewriting Nr1 and Nr2 of vehicle information Iv1 and Iv2, and [3] storage control unit 28 which performs storage control for nonvolatile memory 24 and volatile memory 26. The first storage area 30 includes a first information storage area 30v for storing vehicle information Iv1 and a first number storage area 30n for storing the number of times of rewriting Nr1. Storage area 32 includes a second information storage area 32v in which vehicle information Iv2 is stored, and a second count storage area 32n in which the number of times of rewrite Nr2 is stored.

  [6] Then, the storage control unit 28 writes the number of rewrites Nr1 read from the first number storage area 30n to the volatile memory 26 (6a) before starting the update of the first information storage area 30v (6b) ) Write an unused value (= 0) not used for counting the number of rewrites Nr1 in the first number storage area 30n. [7] The storage control unit 28 counts and updates the number of rewrites Nr1 read from the volatile memory 26 after the update of the first information storage area 30v is completed, and (7b) the first number storage area 30n. Perform storage control to write.

  [8] The storage control unit 28 writes the number Nr2 of rewrites read from the second number storage area 32n to the volatile memory 26 (8a) before starting updating the second information storage area 32v (8b) 2.) Write an unused value (= 0) not used for counting the number of rewrites Nr2 in the second number storage area 32n. [9] The storage control unit 28 counts and updates the number of rewrites Nr2 read from the volatile memory 26 after the update of the second information storage area 32v is completed, and (9b) the second number storage area 32n. Perform storage control to write.

  By configuring in this way, for example, even when the information temporarily stored in the volatile memory 26 is lost due to a momentary power loss, the numerical values of the two rewrite times Nr1 and Nr2 currently stored. The update status of the first storage area 30 and the second storage area 32 can be determined based on the relationship (single value or relative value), and the storage data can be properly recovered by performing the necessary measures thereafter. Thereby, the reliability of stored data can be ensured while reducing the used capacity of the non-volatile memory 24.

  Further, it is more preferable to apply to the engine ECU 12 in which the supply of power is stopped in response to the off operation of the ignition switch 20 of the vehicle. A vehicle that does not have a self-shutdown function after the engine 16 is turned off is particularly effective because data backup of the volatile memory 26 can not be obtained.

[Supplement]
In addition, this invention is not limited to embodiment mentioned above, Of course, it can change freely in the range which does not deviate from the main point of this invention. Or you may combine each structure arbitrarily in the range which a technical contradiction does not arise.

  For example, in this embodiment, the update is performed according to the update order of the first storage area 30 → the second storage area 32, but in the reverse update order (that is, the second storage area 32 → the first storage area 30) May be Also, the update order may not be fixed as long as data synchronization is maintained.

  Moreover, in this embodiment, although the number of times of rewriting Nr1 is stored in the first number of times storage area 30n, an area capable of storing two or more identical values is provided to achieve so-called data multiplexing. It is also good. Specifically, the reliability of the data synchronization process is further improved by determining as a normal value when all the values match or by determining the stored value by majority. The same applies to the second number storage area 32n (number of rewrites Nr2).

10: Vehicle failure diagnosis system 12: Engine ECU (vehicle information storage device)
14 sensor group 16 engine 18 power supply 20 ignition switch 22 arithmetic processing unit 24 non-volatile memory 26 volatile memory 28 storage control unit 30 first storage area 30 n first number storage area 30 v first 1 information storage area 32: second storage area 32n: second number storage area 32v: second information storage area 34: storage area Iv1, Iv2: vehicle information Nr1, Nr2: number of times of rewriting

Claims (5)

A vehicle information storage device mounted on a vehicle and storing vehicle information indicating a state of the vehicle,
A non-volatile memory having a first storage area and a second storage area;
A volatile memory that stores at least the number of times of rewriting of the vehicle information;
A storage control unit that performs storage control on the nonvolatile memory and the volatile memory;
Equipped with
The first storage area includes a first information storage area in which the vehicle information is stored, and a first number storage area in which the number of rewrites is stored.
The second storage area includes a second information storage area in which the vehicle information is stored, and a second number storage area in which the number of rewrites is stored.
The storage control unit
Before starting the update of the first information storage area, the number of rewrites read from the first number storage area is written to the volatile memory, and an unused value not used for counting the number of rewrites is selected. Write to storage area one time,
After the update of the first information storage area is completed, the number of rewrites read out from the volatile memory is counted and updated, and storage control to write in the first number storage area is performed.
Before starting the update of the second information storage area, the number of rewrites read from the second number storage area is written to the volatile memory, and an unused value not used for counting the number of rewrites is selected. Write to storage area 2 times,
After updating of the second information storage area is completed, the number of rewrites read from the volatile memory is counted and updated, and storage control to write in the second number storage area is performed. apparatus. In the vehicle information storage device according to claim 1,
The storage control unit
When the number of rewrites stored in the first number storage area is the non-use value, and the number of rewrites stored in the second number storage area is not the non-use value
Storage control is performed to copy the number of rewrites in the second number storage area and write it in the first number storage area, and copy the vehicle information in the second information storage area and write it in the first information storage area ,
When the number of rewrites stored in the first number storage area is not the nonuse value, and the number of rewrites stored in the second number storage area is the nonuse value
The duplication control of the first number storage area is copied and written in the second number storage area, and the vehicle information of the first information storage area is copied and written in the second information storage area. Vehicle information storage device characterized in that. In the vehicle information storage device according to claim 1,
The storage control unit
When the number of rewrites stored in the first number storage area is larger than the number of rewrites stored in the second number storage area, the vehicle information in the first information storage area is copied, and the second number is stored. Perform storage control to write to the information storage area,
When the number of rewrites stored in the first number storage area is smaller than the number of rewrites stored in the second number storage area, the vehicle information in the second information storage area is copied, and the first number is stored. A vehicle information storage device characterized by performing storage control to write in an information storage area. In the vehicle information storage device according to claim 2 or 3,
The storage control unit does not write to the first storage area and the second storage area other than the copy until the storage control for copying the vehicle information is completed. Storage device. In the vehicle information storage device according to any one of claims 1 to 4,
A vehicle information storage device characterized in that the supply of electric power is stopped in response to the turning-off operation of an ignition switch of the vehicle.

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