Control device and vehicle

Abstract

To reduce useless utilization of a nonvolatile memory in a configuration for storing information on an operation mode in the nonvolatile memory.SOLUTION: An on-vehicle control device for controlling writing to a non-volatile memory includes: writing means for writing data corresponding to a drive mode of a vehicle to the non-volatile memory when the drive mode satisfies a reference; measuring means for measuring the number of times of writing by the writing means; and limiting means for limiting an amount of data to be written in the nonvolatile memory by the writing means based on measurement results of the measuring means.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates mainly to an in-vehicle control device. [Background technology]

[0002] Patent Document 1 describes the configuration of an event data recorder (EDR) as a device that stores information indicating the details of a vehicle's driving behavior when the behavior satisfies a standard, such as sudden deceleration, in an on-board nonvolatile memory. According to Patent Document 1, when the remaining memory capacity of the nonvolatile memory falls below a standard, the information to be written in the nonvolatile memory is transmitted to a server outside the vehicle via a communication device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-120792 Summary of the Invention [Problem to be solved by the invention]

[0004] Since it may be difficult to achieve appropriate communication depending on the communication environment, it may be necessary to store the information in a non-volatile memory on board the vehicle. On the other hand, semiconductor memory such as a flash memory is typically used as the non-volatile memory, and from the viewpoint of the number of write cycles and the associated reliability, it is desirable to prevent unnecessary use of the non-volatile memory.

[0005] The present invention was made in response to the recognition of the above-mentioned problems, and has an exemplary object to prevent unnecessary use of nonvolatile memory in a configuration in which information on driving modes is stored in the nonvolatile memory. [Means for solving the problem]

[0006] One aspect of the present invention relates to a control device, the control device comprising: A vehicle equipped with a wheel and a driving assistance device that performs predetermined driving assistance,To control writing to non-volatile memory of A control device, The aforementioned a writing means for writing data corresponding to the driving behavior of the vehicle into the nonvolatile memory when the driving behavior satisfies a standard; a counting means for counting the number of writes by the writing means; a limiting means for limiting the amount of data that the writing means writes to the nonvolatile memory based on the measurement result of the measuring means. 、 The driving assistance includes two or more modes with different driving assistance levels, and when the limiting means limits the amount of data that the writing means writes to the nonvolatile memory, the driving assistance is changed to a mode with a lower driving assistance level. R It is characterized by: [Effects of the Invention]

[0007] According to the present invention, it is possible to prevent unnecessary use of the nonvolatile memory. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing a system configuration of a vehicle. [Figure 2] 10 is a flowchart illustrating a method for controlling writing to a nonvolatile memory. [Figure 3] 10 is a table showing a method for managing contents written to a nonvolatile memory. [Figure 4] FIG. 10 is a schematic diagram showing a method for measuring the number of writes to a nonvolatile memory. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims, and not all combinations of features described in the embodiments are necessarily essential to the invention. Two or more of the features described in the embodiments may be arbitrarily combined. Furthermore, the same reference numerals are used for the same or similar components, and redundant explanations will be omitted.

[0010] First Embodiment (System configuration) 1 is a block diagram showing an example of the system configuration of a vehicle 1 according to the first embodiment. The vehicle 1 includes wheels 11, a driving operation device 12, a detection device 13, a driving assistance device 14, a volatile memory 15, a non-volatile memory 16, a control device 17, and a position identification device 18. In this embodiment, the vehicle 1 is a four-wheeled vehicle having two front wheels and two rear wheels as the wheels 11, but in other embodiments, the vehicle 1 may be a two-wheeled vehicle or a three-wheeled vehicle, and the number of wheels 11 is not limited to that in this example.

[0011] The driving operation device 12 includes an acceleration operator 121, a deceleration operator 122, and a steering operator 123. Generally, an accelerator pedal is used as the operator 121, and a brake pedal may be used as the operator 122. A steering wheel may be used as the operator 123. Other types of operators, such as levers or buttons, may also be used for the operators 121 to 123.

[0012] The detector 13 detects the driving behavior of the vehicle 1. The driving behavior typically indicates factors directly or indirectly related to the longitudinal and / or lateral speed and acceleration of the vehicle 1. Examples of such factors include the amounts of operation of the operators 121-123 that realize acceleration, deceleration, and steering of the vehicle 1, or physical quantities corresponding thereto. As an example, the detector 12 detects the amounts of operation of each of the operators 121-123.

[0013] It should be noted that the contents of detection by the detection device 13 are not limited to those in this example, and the detection device 13 is capable of detecting various states of the vehicle 1 regardless of whether the vehicle 1 is moving or not, and is capable of acquiring information indicating the states.

[0014] The detection results of the detection device 13 can be stored in the volatile memory 15, which will be described later, together with related information at the time of the detection. Examples of this related information include time information indicating the time at which the detection occurred, and location information indicating the location of the vehicle 1 on the map data at the time of the detection.

[0015] The driving assistance device 14 performs predetermined driving assistance. The concept of driving assistance includes assisting in at least one of acceleration, deceleration, and steering. With such driving assistance device 14, the vehicle 1 has a driving assistance mode and a manual driving mode as operation modes. In the driving assistance mode, the driving assistance device 14 assists with some or all of the acceleration, deceleration, and steering operations, thereby reducing the burden on the occupant as a driver. On the other hand, in the manual driving mode, the occupant is the main driver of the vehicle 1, and performs all of the acceleration, deceleration, and steering operations as the driver.

[0016] In addition, when the driving assistance device 14 assists with all acceleration, deceleration, and steering operations, the driving operation of the vehicle 1 is mainly performed by the driving assistance device 14, and such an operating mode may be referred to as an automatic driving mode and distinguished from the driving assistance mode.

[0017] The concept of driving assistance may include not only direct assistance with driving operations but also indirect assistance. Therefore, the driving assistance device 14 may further perform, for example, calculation processing of a driving route to a destination and notification of the route to the passenger or driver.

[0018] The volatile memory 15, the details of which will be described later, temporarily stores the detection results of the detection device 13. For the volatile memory 15, a DRAM (dynamic random access memory) can generally be used.

[0019] The nonvolatile memory 16, the details of which will be described later, can store part of the detection results of the detection device 13 that are temporarily stored in the volatile memory 15. A known semiconductor memory or semiconductor element memory may be used for the nonvolatile memory 16, and main examples thereof include NAND flash memories such as eMMC (embedded multi media card), UFS (universal flash storage), and SSD (solid state drive), but NOR flash memories may also be used.

[0020] The control device 17 continuously stores the detection results of the detection device 13 in the volatile memory 15, and selects a portion of the detection results and stores them in the non-volatile memory 16 when a predetermined condition is met. That is, the detection device 13 continuously detects the driving manner of the vehicle 1, and the detection results are sequentially written to the volatile memory 15. On the other hand, when a predetermined condition is met, a corresponding portion of the detection results written in the volatile memory 15 is selected and written to the non-volatile memory 16.

[0021] Examples of the above condition being met include when the absolute value of acceleration when accelerating the vehicle 1 is greater than a reference value, and when the absolute value of acceleration when decelerating the vehicle 1 is greater than a reference value. Another example of the above condition being met is when an impact value applied to the vehicle 1 from the outside is greater than a reference value. Therefore, when an unexpected event occurs in the vehicle 1, that is, when the driving manner of the vehicle 1 satisfies the criterion, the detection result of the detection device 13 may be selectively written to the non-volatile memory 16.

[0022] Each function of the control device 17 may be implemented by either software or hardware. For example, the functions of the control device 17 may be implemented by one or more processor circuits with memory individually reading and executing programs. Alternatively, the functions may be implemented by driving corresponding circuit units (e.g., ASICs (Application Specific Integrated Circuits)).

[0023] The position identification device 18 identifies the position of the vehicle 1 on map data of the vehicle 1, and is capable of acquiring the position information. An example of the position identification device 18 is a GNSS (Global Navigation Satellite System) sensor. Examples of map data include those typically used in car navigation systems, such as HD (High-definition) maps and SD (Standard) maps. As another example, an environmental map generated or updated based on information about past travels of the vehicle 1 may be used. For example, the driving assistance device 14 described above can provide driving assistance based on the position information acquired by the position identification device 18.

[0024] These elements 12 to 18 are capable of sending and receiving signals via a system bus or the like, and with this configuration, the control device 17 controls writing to the non-volatile memory 16, and in this embodiment, if an unforeseen event occurs in the vehicle 1, part of the detection results of the detection device 13 is stored in the non-volatile memory 16 as information (or data) indicating the event.

[0025] Although these elements 12 to 18 are shown as individual units here for ease of explanation, at least some of their functions may be provided separately or integrated with other parts. That is, the elements 12 to 18 may be formed by one or more ECUs (electronic control units), and multiple ECUs may be installed at corresponding positions on the vehicle 1 depending on the functions and uses.

[0026] In the following description, an unexpected event that occurs in the vehicle 1 may be referred to as an "event," and information written to the non-volatile memory 16 may be referred to as "event data." Because the event data is written as a record to the non-volatile memory 16, the control device 17, together with the detection device 13 and the non-volatile memory 16 (and, incidentally, the volatile memory 15), may be referred to as an "event data recorder." Event data is erased from the non-volatile memory 16 after a predetermined period of time has elapsed or in order from oldest to newest, and is overwritten with new data.

[0027] (Regarding utilization of non-volatile memory) In addition to the event data described above, information (or data) necessary for realizing driving assistance in the driving assistance mode is written by the control device 17 to the nonvolatile memory 16. The information to be written to the nonvolatile memory 16 in the driving assistance mode is regulated by predetermined laws and regulations, and examples thereof include: "Attachment 123: Technical Standards for Operational Status Recording Devices" of "Safety Standards for Road Transport Vehicles (as of April 28, 2021)," Ministry of Land, Infrastructure, Transport and Tourism, https: / / www.mlit.go.jp / common / 001346769.pdf Examples include:

[0028] Therefore, if the above-mentioned event data is unnecessarily written to the nonvolatile memory 16 at a high frequency, the nonvolatile memory 16 will be deteriorated early. This may cause difficulty in utilizing the nonvolatile memory 16 in the driving assistance mode, or even in executing the driving assistance itself. Therefore, it is necessary to suppress or reduce unnecessary writing of event data to the nonvolatile memory 16.

[0029] 2 is a flowchart showing an example of a method for controlling the writing of event data to nonvolatile memory 16. This flowchart is mainly executed by control device 17, and the outline thereof is to limit the amount of event data to be written to nonvolatile memory 16 when the number of times data is written to nonvolatile memory 16 is large. Furthermore, this flowchart is started in response to the start of vehicle 1 (when vehicle 1 becomes ready to drive), regardless of whether the vehicle is in the driving assistance mode or the manual driving mode.

[0030] In step S2000 (hereinafter simply referred to as "S2000"; the same applies to other steps described below), the control device 17 acquires the detection results of the detection device 13 (information indicating the driving mode of the vehicle 1) and writes them to the volatile memory 15. From this perspective, the control device 17 can be said to function as an acquisition unit and a writing unit.

[0031] In S2010, the control device 17 determines whether an event (unforeseen event) has occurred. From this perspective, the control device 17 can be said to function as a determination unit. Here, as an example, it is determined that an event has occurred in response to the absolute value of the acceleration occurring in the vehicle 1 becoming greater than a reference value. Therefore, the determination in S2010 can be made substantially simultaneously with writing the detection result of the detection device 13 to the volatile memory 15 (S2000). Furthermore, the determination in S2010 may be made based on an acceleration sensor that may typically be mounted on the vehicle 1, but alternatively / accompanyingly, it may also be made based on the detection result of the detection device 13. If an event has occurred, the process proceeds to S2020; if not, the process returns to S2000.

[0032] Here, if no event has occurred, the process returns from S2010 to S2000, and therefore, as described above, the detection device 13 continuously detects the driving mode of the vehicle 1, and the detection results are constantly written to the volatile memory 15. Note that the detection results of the detection device 13 written to the volatile memory 15 in S2000 are erased, for example, after a predetermined time has elapsed; that is, relatively new detection results are temporarily stored in the volatile memory 15.

[0033] In S2020, the control device 17 generates a signal Sig0 indicating that the event data is to be written to the nonvolatile memory 16. From this perspective, the control device 17 can be said to function as a signal generating unit. As will be described in detail later, based on the signal Sig0, some of the correspondences among the examination results stored in the volatile memory 15 are read out. Here, the control device 17 has a built-in counter, and counts up a value Val0 indicating the number of writes to the nonvolatile memory 16 as the signal Sig0 is generated.

[0034] In the following description, the signal Sig0 may be referred to as the write execution signal Sig0, and the value Val0 may be referred to as the write count measurement value Val0.

[0035] In S2030, the control device 17 determines whether the write count measurement value Val0 is equal to or greater than the threshold value Val. TH1 From this point of view, the control device 17 can be said to function as a determining unit. TH1 If so, proceed to S2040, otherwise (Val0 <Val TH1 In this case, proceed to S2110.

[0036] In S2040, the control device 17 determines whether the write count measurement value Val0 is equal to or greater than the threshold value Val. TH2 (>Val TH1 From this point of view, the control device 17 functions as a determining unit. TH2 If so, proceed to S2310, otherwise (Val0 <Val TH2 In this case, proceed to S2210.

[0037] In S2110, the control device 17 reads a part of the detection result of the detection device 13 from the volatile memory 15 based on the execution signal Sig0, and writes the part as event data to the non-volatile memory 16. From this point of view, the control device 17 can be said to function as a reading unit and a writing unit. Here, in S2110, Val0 <Val TH1 Therefore, it can be said that the number of times the event data is written to the nonvolatile memory 16 is relatively small. Therefore, the event data written to the nonvolatile memory 16 in S2110 only needs to be an amount of data based on a predetermined standard (this will be referred to as event data D1 to distinguish it from other event data described later). The event data D1 is the detection result of the detection device 13 for a predetermined period based on the timing of generation of the signal Sig0.

[0038] In S2210, Val TH1 ≦Val0 <Val TH2It can be said that the number of times the event data is written to the nonvolatile memory 16 is relatively large. Therefore, in S2210, the amount of event data to be written to the nonvolatile memory 16 is more limited than in S2110, and the event data with the limited amount of data (referred to as event data D2 for the sake of distinction) is written to the nonvolatile memory 16. From this perspective, it can be said that the control device 17 functions as a reading unit, a writing unit, and a limiting unit.

[0039] Here, in S2210, the driving assistance device 14 may additionally be notified that the number of writes to the non-volatile memory 16 is relatively large. The driving assistance mode may include two or more modes with different driving assistance levels (degrees of driving assistance). In this case, the driving assistance device 14 changes the current mode to a mode with a lower driving assistance level based on the above notification, thereby making it possible to impose a predetermined restriction on the information to be written to the non-volatile memory 16 in the driving assistance mode.

[0040] For example, if the driving assistance mode includes a first mode and a second mode with a lower driving assistance level, and the driving assistance device 14 is executing the first mode at the time of the notification, the driving assistance device 14 can change the driving assistance mode from the first mode to the second mode in response to the notification. If the driving assistance mode includes three or more modes, the driving assistance mode may be changed to a mode with a lower driving assistance level in a stepwise manner.

[0041] In S2310, Val0 ≥ Val TH2 It can be said that the number of times the event data is written to the nonvolatile memory 16 is even greater. Therefore, in S2310, the amount of event data to be written to the nonvolatile memory 16 is further limited compared to S2210, and the event data with the further limited amount of data (referred to as event data D3 for the sake of distinction) is written to the nonvolatile memory 16. From this perspective, it can be said that the control device 17 functions as a reading unit, a writing unit, and a limiting unit.

[0042] As in S2210, in S2310, the driving assistance device 14 may be notified that the number of writes to the non-volatile memory 16 is even greater. In this case, the driving assistance mode may be changed to one with a lower driving assistance level than in S2210, for example, one that does not require the recording of event data, or may be changed to a manual driving mode.

[0043] Furthermore, the threshold value Val TH1 and Val TH2 For example, a value of several hundred or several thousand may be set for the nonvolatile memory 16, but the present invention is not limited to this and a value based on the design of the nonvolatile memory 16 may be set in advance.

[0044] Here, with regard to the above-described event data D1, D2, and D3 indicating the detection results of the detection device 13, limiting the data volume only requires that the area used in the nonvolatile memory 16 be reduced, and essentially corresponds to a small data size itself. Therefore, for example, if the detection device 13 detects multiple items (e.g., acceleration, deceleration, steering, etc.) and the event data D1 indicates the detection results of the multiple items, the event data D2 or D3 may indicate the detection results of only a portion of the multiple items. Furthermore, for example, if the event data D1 indicates the detection results for a predetermined period based on the timing of the generation of the signal Sig0, the event data D2 or D3 may indicate the detection results for a shorter period. Furthermore, if the number of times the event data is written to the nonvolatile memory 16 (i.e., the measurement value Val0) is unnecessarily large, the control device 17 limits the amount of event data to be written to the nonvolatile memory 16. This reduces the area of ​​the nonvolatile memory 16 used when writing event data, appropriately prevents unnecessary use of the nonvolatile memory 16, and thus reduces deterioration of the nonvolatile memory 16.

[0045] The write count measurement value Val0 is the upper limit (>Val TH2 ), here Val TH1 ≦Val0 <Val TH2is established, the nonvolatile memory 16 should be replaced with a new one. Therefore, in such a case, the occupant or the driver should be notified that the nonvolatile memory 16 needs to be replaced. This may be realized by a device (such as a liquid crystal display) that the driving assistance device 14 may additionally include, or may be realized by a sound source that may typically be installed in the vehicle 1. In this case, the execution of the driving assistance mode may be additionally restricted.

[0046] As described above, according to this embodiment, when the driving manner of the vehicle 1 satisfies a criterion, the control device 17, when writing event data to the nonvolatile memory 16, limits the amount of the event data based on the measurement result of the number of times the event data is written to the nonvolatile memory 16. The more times the event data is written, the larger the limited amount of data becomes. Therefore, unnecessary use of the nonvolatile memory 16 is appropriately prevented, and deterioration of the nonvolatile memory 16 can be suppressed.

[0047] Furthermore, when the driving assistance mode includes two or more modes with different driving assistance levels, the driving assistance device 14 can perform driving assistance in a mode with a relatively low driving assistance level even after limiting the amount of event data to be written to the nonvolatile memory 16. Therefore, driving assistance can be utilized in a mode with a relatively low driving assistance level until the nonvolatile memory 16 is replaced, for example, until the vehicle 1 arrives at a repair shop.

[0048] In this embodiment, the event data D1 is the detection result of the detection device 13 for a predetermined period based on the timing of the occurrence of the signal Sig0, but the detection result may also include results from a period before the occurrence of the signal Sig0 and a period after the occurrence of the signal Sig0. That is, not only the driving behavior of the vehicle 1 before the occurrence of the event, but also the driving behavior of the vehicle 1 after the occurrence of the event may be recorded as event data in the non-volatile memory 16. This can be achieved by reading from the volatile memory 15 the detection results that are continuously detected by the detection device 13 and continuously written to the volatile memory 15 even after the occurrence of the signal Sig0, and writing them to the non-volatile memory 16.

[0049] In addition, in this embodiment, a counter built in the control device 17 is used to measure the write count measurement value Val0, but the counter may be provided separately from the control device 17, for example, it may be provided in the nonvolatile memory 16. Note that the measurement of the measurement value Val0 by the counter may be performed by counting down, that is, it is sufficient if it is measured cumulatively.

[0050] Furthermore, in this embodiment, in addition to the event data, information necessary for realizing the driving assistance mode is also written to the nonvolatile memory 16, but the configuration of the storage device is not limited to this example as long as unnecessary use of the nonvolatile memory 16 is appropriately prevented. Therefore, in another embodiment, for example, another nonvolatile memory into which information necessary for realizing the driving assistance mode is to be written may be provided separately from the nonvolatile memory 16.

[0051] Second Embodiment The data amounts of the event data written to the nonvolatile memory 16 may be standardized, for example, as 32 KB (kilobytes) for event data D1, 16 KB for event data D2, and 8 KB for event data D3. Therefore, it may be necessary to measure the number of writes in a manner corresponding to the standardization.

[0052] Therefore, in the first embodiment, an example was given in which the signal Sig0 is generated in response to the occurrence of an event and the write count measurement value Val0 is counted up (see S2020 in Figure 2), but it is preferable that the measurement value Val0 be measured for each specified area of ​​the non-volatile memory 16.

[0053] For example, in the example of the event data D1 (32 KB), event data D2 (16 KB), and event data D3 (8 KB), the unit block is 8 KB, and four blocks are used for the event data D1, two blocks are used for the event data D2, and one block is used for the event data D3. These blocks can also be expressed as memory blocks.

[0054] Generally, memory capacity is managed for each address, so by assigning a single address to each memory block, it becomes possible to measure the measurement value Val0 for each address.

[0055] For example, as shown in FIG. 3(a), the measurement value Val0 may be measured and managed for each physical address of the nonvolatile memory 16. As another example, as shown in FIG. 3(b), the measurement value Val0 may be measured for each event data and managed for two or more physical addresses. In these cases, a counter for measuring the measurement value Val0 may be provided in the nonvolatile memory 16. The control device 17 may obtain information indicating the measurement value Val0 from the nonvolatile memory 16.

[0056] 3(c), a logical address is associated with the physical address of the nonvolatile memory 16 so that the physical address can be accessed by an external device. The write count value Val0 may be managed using this logical address.

[0057] Furthermore, the capacity of a single address in the memory may differ depending on the device structure of the nonvolatile memory 16. Therefore, the measurement value Val0 may be managed for each physical address as in the example of Fig. 3(a), but it is preferable to manage it for each event data when two or more physical addresses are required to record the event data as in the example of Fig. 3(b).

[0058] Furthermore, if the write count measurement value Val0 of a physical address associated with a logical address is larger than the measurement values ​​Val0 of other physical addresses, the logical address may be reassociated with a physical address with a smaller measurement value Val0 (a physical address with fewer write counts). This makes it possible to reduce the difference in write count measurement values ​​Val0 between those physical addresses, i.e., to equalize the number of writes among multiple memory blocks.

[0059] If the counter is provided in the nonvolatile memory 16, the control device 17 can use a page table indicating the correspondence between logical addresses and physical addresses when obtaining information indicating the write count measurement value Val0 from the nonvolatile memory 16.

[0060] 4, a monitoring unit 19 may be further provided to monitor data transferred from the volatile memory 15 to the nonvolatile memory 16. The monitoring unit 19 may be provided to monitor a system bus connecting the elements 12 to 18, or may be provided to monitor input data to the nonvolatile memory 16. This makes it possible to measure the write count measurement value Val0 based on the monitoring results of the monitoring unit 19. In this case, the control device 17 may obtain information indicating the write count measurement value Val0 from the monitoring unit 19.

[0061] According to this measurement mode, the nonvolatile memory 16 can be utilized so that the number of writes to multiple blocks is averaged. In this case, whether or not to limit the amount of event data to be written to the nonvolatile memory 16 may be determined based on the calculated value (e.g., average value, maximum value, total value, etc.) of the measurement value Val0.

[0062] In the above description, for ease of understanding, each element is denoted by a name related to its function. However, each element is not limited to having the content described in the embodiment as its main function, and may have that function auxiliary to the content. Therefore, each element is not strictly limited to the expression, and the expression can be replaced with a similar expression. In the same spirit, the expression "apparatus" may be replaced with "unit," "component," "piece," "member," "structure," "assembly," etc., or may be omitted.

[0063] For example, the nonvolatile memory 16 may be expressed as a nonvolatile memory section, a nonvolatile memory device, or the like to distinguish it from a memory cell.

[0064] According to the above-described embodiment, it is possible to prevent unexpected stoppage of the driving assistance and to make a highly convenient vehicle available for a wide range of uses, which can contribute to building a foundation for industry and technological innovation and further promoting welfare in a diversifying society. Furthermore, it is possible to prevent an unnecessary increase in the number of writes to the nonvolatile memory 16 and / or to make appropriate use of the nonvolatile memory 16, which can contribute to reducing or preventing unnecessary disposal of the nonvolatile memory 16.

[0065] (Summary of the embodiment) Some features of the above embodiments can be summarized as follows: A first aspect relates to a control device (e.g., 17), the control device comprising: An in-vehicle control device for controlling writing to a non-volatile memory (e.g., 16), A writing means (e.g., S2110, S2210, S2310) for writing data corresponding to the driving behavior of the vehicle to the nonvolatile memory when the driving behavior satisfies a standard; A counting means (e.g., S2020) for counting the number of writes by the writing means; and limiting means (e.g., S2110, S2210, S2310) for limiting the amount of data that the writing means writes to the nonvolatile memory based on the measurement result of the measuring means. According to this feature, the event data can be stored without the nonvolatile memory being used unnecessarily.

[0066] The second aspect is The greater the number of times the write operation is performed, the greater the limited data amount becomes. According to this feature, it is possible to appropriately prevent unnecessary use of the nonvolatile memory.

[0067] The third aspect is The measuring means measures the number of writes for each address of the nonvolatile memory. According to this feature, it is possible to appropriately utilize a plurality of areas of the nonvolatile memory.

[0068] The fourth aspect is The driving manner of the vehicle satisfies the criteria, the absolute value of acceleration during acceleration of the vehicle is greater than a reference value; The absolute value of the acceleration when the vehicle is decelerating is greater than a reference value; and The impact value applied to the vehicle from the outside is greater than a reference value. Contains at least one of According to this feature, the event data can be stored.

[0069] The fifth aspect is The non-volatile memory includes a semiconductor memory (e.g., 16). The above-described control device is applicable to realizing control of writing to a semiconductor memory such as a flash memory.

[0070] The sixth aspect is The device further includes a notification means (e.g., 14) for notifying that the nonvolatile memory needs to be replaced based on the measurement result of the measurement means. According to this feature, the vehicle user can appropriately replace the nonvolatile memory. Although the embodiment illustrates the replacement of the nonvolatile memory alone, the entire unit in which the nonvolatile memory is implemented, such as a memory ECU, may be replaced.

[0071] A seventh aspect relates to a vehicle (e.g., 1), the vehicle comprising: A control device (e.g., 17) according to any one of claims 1 to 6; Wheels (e.g., 11), A driving assistance device (e.g., 14) that performs predetermined driving assistance. That is, the control device described above is applicable to a typical vehicle.

[0072] The eighth aspect is A detection device (e.g., 13) that detects the driving mode; a volatile memory (e.g., 15) for temporarily storing the detection result of the detection device; and a non-volatile memory (e.g., 16); When the detection result satisfies the criterion, the writing means writes the corresponding part of the data temporarily stored in the volatile memory to the nonvolatile memory. According to this feature, the event data can be stored without the nonvolatile memory being used unnecessarily.

[0073] A ninth aspect is The writing means further writes information necessary for executing the driving assistance into the nonvolatile memory. That is, the above-described control device is applicable to a typical vehicle equipped with a driving assistance device.

[0074] A tenth aspect is The driving assistance includes at least one of an acceleration operation, a deceleration operation, and a steering operation. According to such a feature, it is possible to appropriately realize driving assistance for all of acceleration operation, deceleration operation, and steering operation.

[0075] An eleventh aspect is The driving assistance includes two or more modes with different driving assistance levels, When the limiting means limits the amount of data that the writing means writes to the nonvolatile memory, the driving assistance device changes the driving assistance to a mode with a lower driving assistance level. According to such a feature, driving assistance at a relatively low level can be used without unnecessarily utilizing the nonvolatile memory.

[0076] A twelfth aspect is The writing means writes the data corresponding to the driving behavior into the nonvolatile memory when receiving an instruction from the driving assistance device to write the data into the nonvolatile memory. According to this feature, data required for realizing driving assistance can be recorded in the nonvolatile memory.

[0077] The invention is not limited to the above-described embodiment, and various modifications and variations are possible within the scope of the gist of the invention. [Explanation of symbols]

[0078] 1: Vehicle, 16: Non-volatile memory, 17: Control device.

Claims

1. A control device for controlling writing to a non-volatile memory, configured to be mountable on a vehicle having wheels and a driving assistance device that performs predetermined driving assistance, comprising: a writing means for writing data corresponding to the driving behavior of the vehicle into the nonvolatile memory when the driving behavior of the vehicle satisfies a standard; a counting means for counting the number of writes by the writing means; a limiting means for limiting the amount of data that the writing means writes to the nonvolatile memory based on the measurement result of the measuring means; The driving assistance includes two or more modes with different driving assistance levels, and when the limiting means limits the amount of data that the writing means writes to the nonvolatile memory, the driving assistance is changed to a mode with a lower driving assistance level. A control device characterized by:

2. The greater the number of times the write operation is performed, the greater the limited data amount becomes.

2. The control device according to claim 1.

3. The measuring means measures the number of writes for each address of the nonvolatile memory.

3. The control device according to claim 1 or 2.

4. The driving manner of the vehicle satisfies the criteria, the absolute value of acceleration during acceleration of the vehicle is greater than a reference value; The absolute value of the acceleration when the vehicle is decelerating is greater than a reference value; and The impact value applied to the vehicle from the outside is greater than a reference value. Contains at least one of 4. The control device according to claim 1, wherein the control device comprises: a first electrode;

5. The nonvolatile memory includes a semiconductor memory.

5. The control device according to claim 1, wherein the control device comprises: a first electrode;

6. The nonvolatile memory may be replaced based on the measurement result of the measuring means.

6. The control device according to claim 1, wherein the control device comprises: a first electrode;

7. A control device according to any one of claims 1 to 6; Wheels and a driving assistance device that performs predetermined driving assistance; A vehicle characterized by:

8. a detection device for detecting the driving mode; a volatile memory for temporarily storing the detection result of the detection device; a non-volatile memory, When the detection result satisfies the criterion, the writing means writes the corresponding part of the data temporarily stored in the volatile memory to the nonvolatile memory.

8. The vehicle according to claim 7.

9. The writing means further writes information necessary for executing the driving assistance into the nonvolatile memory.

9. The vehicle according to claim 7 or 8.

10. The driving assistance includes at least one of an acceleration operation, a deceleration operation, and a steering operation.

10. A vehicle according to any one of claims 7 to 9.

11. The writing means writes the data corresponding to the driving behavior into the nonvolatile memory when receiving an instruction from the driving assistance device to write the data into the nonvolatile memory.

11. A vehicle according to any one of claims 7 to 10.

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