JP2002106411A - Vehicular data storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cope with occurrences of plural times of events for analyzing the cause of the occurrence of the event such as a failure on the basis of the stored detection value of a sensor. SOLUTION: The device has a first control unit U1 for performing a fault diagnosis by controlling the engine and a second control unit U2 for controlling a data storage control. When an IG switch is turned on, the detection values of the sensor on the engine rotating speed, the vehicle speed, etc., are, together with a failure code, addressed onto both of the memories M1, M2, then updated and stored. In case a fault detection related event such as lighting of a warning lamp occurs, writing onto the first memory is prohibited. Afterward, the detection value of the sensor is addressed onto the second memory M2, then updated and stored. Furthermore, writing onto the second memory M2 is prohibited when a next event occurs. Only a part of the detection value of the sensor associated with the first fault occurrence can be made to be updated and stored on the second memory M2. The detection value of the sensor can be updated and stored after being thinned out in accordance with the processing burden of the writing control part 21 to control updating and storing onto memories M1, M2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle data storage device.

[0002]

2. Description of the Related Art A vehicle is equipped with many devices such as an engine, an automatic transmission, an airbag, and an air conditioner.
When an event such as a failure or abnormality occurs in these devices, or when an event such as activation of an airbag occurs, it is desired that the cause of the occurrence of these events can be easily analyzed. Japanese Patent Application Laid-Open No. H11-65647 discloses a system in which a failure history is stored in a PC card that can be taken out of a vehicle. JP-A-8-12123
Japanese Patent Publication No. 8 discloses that a peak hold value of the engine speed is stored in a memory at predetermined intervals. In Japanese Patent Application Laid-Open No. 9-183360, the vehicle acceleration is always stored in a RAM, and when the airbag is activated, the vehicle acceleration before and after that is stored in the memory.
There is disclosed one in which writing to a memory thereafter is prohibited.

[0003]

However, if the writing of the memory storing and updating the sensor detection value is prohibited at the time of occurrence of the event, the subsequent event cannot be handled. That is, depending on the content of the failure or the vehicle accident, a second event occurrence may occur after the first event occurrence, and there may be a considerable causal relationship between the two event occurrences.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle data storage device capable of analyzing the cause even if an event occurs a plurality of times. is there.

[0005]

In order to achieve the above object, according to the present invention, basically, at least two memories are used to store a sensor detection value every time an event occurs. I can do it.

Specifically, the present invention adopts the following solution. That is, as described in claim 1 of the claims, the sensor detection value is constantly updated and stored in an address designated area of the memory, and is written to the memory when a preset event occurs or after that. A vehicle data storage device provided with storage control means for prohibiting the occurrence of an event, wherein at least two memories, a first memory and a second memory, are provided as the memories, and the storage control means When an event occurs, the sensor detection value is updated and stored after addressing both the first memory and the second memory, and when the first event occurs, writing to the first memory is inhibited. Then, the subsequent sensor detection value is updated and stored after addressing only the second memory, and when the second event occurs, the writing to the second memory is also prohibited. And Aru.

In the present invention, the following solution is adopted. That is, as described in claim 2 of the claims, a vehicular data storage device provided with a storage control means for storing a sensor detection value in an address designated area of a memory when a preset event occurs. At least two memories, a first memory and a second memory, are provided as the memories, and the storage control means addresses the sensor detection value only in the first memory when the event does not occur. To update and store at the time of the first occurrence of the event, prohibit writing to the first memory, and select a subsequent sensor detection value according to the first occurrence of the event. The address is stored in the memory after the address is specified, and when the second event occurs, the writing to the second memory is also prohibited.

[0008] Preferred embodiments based on the above-mentioned respective solutions are as described in claim 3 and the following claims.

[0009]

According to the first aspect of the present invention, since the sensor detection value is stored in a separate memory for each event occurrence, not only the cause of each event occurrence but also a plurality of event occurrences It is possible to perform analysis including the causal relationship in the above.

According to the second aspect of the present invention, since the sensor detection value is stored in a separate memory for each event occurrence, not only the cause of each event occurrence but also the plurality of occurrence events It is possible to perform an analysis including the causal relationship of Also, the update storage after the first event occurrence is 1
Since the detection is performed by selecting the sensor detection value corresponding to the event that has occurred at the time of the event, the cause analysis of the event occurrence can be more easily performed.

According to the third, fourth, and fifth aspects of the present invention, it is preferable to minimize the load of the update storage.

According to the invention described in claim 6, it is possible to set only one data reading portion.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the control system diagram of FIG.
Is a first control unit for the engine, U2 is a second control unit for data storage control, and U3 is a third control unit for navigation. The first control unit U1 controls the operation of the engine according to various input signals, and the control unit U1 outputs detection values from various sensors related to the engine to the second control unit U2. The sensor detection value includes, for example, the engine speed, the throttle opening, the vehicle speed, the coolant temperature, and the ON / OFF state of the brake switch.
Further, the first control unit U1 transmits a failure code signal indicating the content of the failure to the second control unit U2 when any failure occurs and the warning lamp is turned on. In the embodiment, the warning lamp is turned on when a predetermined event occurs.

The third control unit U3 is, as known,
The current position obtained by using the GPS sensor is recorded on CD or DV
The current position of the vehicle on the road map is specified by collating with the road map information stored in D or the like. Then, on the display screen, the road map and the current position of the vehicle are displayed. Further, the third control unit U3 uses the wireless communication means 1 such as a mobile phone to communicate with the information center 2 that transmits outside-vehicle information via the Internet or the like as shown in FIG. The information outside the vehicle obtained by the communication is input to the second control unit U2. In FIG. 2, a vehicle having the control system shown in FIG.

As the outside-of-vehicle information, information which affects the breakdown of a vehicle or an accident is selected. Snowfall, etc.), traffic information (traffic regulation, traffic congestion information, etc.), event occurrence cases near the current position of the vehicle, disaster information, etc. In the embodiment, the outside-of-vehicle information is updated and stored together with the sensor detection value in order to easily and accurately determine the cause of the occurrence of the event.

The second control unit U2 has a CPU 11 that controls the entire system. The CPU 11 receives data values such as the detected values of various sensors such as the engine speed via an input I / F 12, receives a failure code signal via a malfunction / failure detection unit 13, and outputs information outside the vehicle. Is input via the communication unit 14. The CPU 11
, A command signal from the operation switch group 15 that is manually operated is input via the operation switch processing unit 16. The operation switch group 15 includes a second control unit U
In addition to a main switch for turning ON and OFF the switch 2, a switch for issuing a command to transfer stored sensor detection values and information outside the vehicle to the outside of the vehicle as described later is included.

Data transfer from the memories M1 and M2, that is, readout of stored data to the outside is performed via the transfer unit 17, but this transfer is set to be performed only from the second memory M2. That is, the transfer or reading of the storage data of the first memory M1 is performed via the second memory M2 after the storage data of the first memory M1 is temporarily copied to the second memory M2.

The second control unit U2 further has a control unit 21 for writing data. This control unit 21
U22 and DPRAM (dual port RAM) 23. The control unit 21 controls writing to the first memory M1 including an SRAM and the second memory M2 including a flash memory as a nonvolatile memory. That is, the CPU 22 receives a data write signal from the CPU 11, and
The writing of the above-described sensor detection value and the information outside the vehicle to the first memory M1 or the second memory M2 is controlled. The data stored in the memories M1 and M2 is DPRA
The data can be transferred from the transfer unit 17 to the outside of the vehicle via M23. The transfer of the stored data is performed in response to the operation of the transfer command switch included in the switch group 15.

Next, a first control unit U1 and a second control unit U2 related to writing data to the memories M1 and M2.
Will be described with reference to the flowcharts of FIGS. In the embodiment, a warning lamp is turned on when a failure or abnormality occurs in a device (an engine in the embodiment) controlled by the first control unit U1, and at least when a warning lamp is turned on, a predetermined preset value is set. It is assumed that the event has occurred. And when the warning lamp is turned on,
In other words, a plurality of types of failures or abnormalities are set, for example, when the temperature of the cooling water rises above a predetermined temperature, when the amount of engine oil falls below a predetermined amount, or when the engine stalls. Only one may be provided, or each may be provided individually for each failure or abnormality. Then, immediately after the ignition switch is turned on, an initial check is performed to determine whether or not the warning lamp is disconnected. The lighting of the warning lamp at the time of the initial check is not regarded as an event occurrence. In the following description, Q or R indicates a step.

First, referring to FIG. 3 showing an outline of the overall control in the first control unit U1, after confirming that the first control unit U1 has been activated in Q1, the IG switch is turned on. Confirmation)
In Q2, the centering of the warning lamp is checked as described later. Next, in Q3, normal control (for example, fuel injection amount control, ignition timing control, and the like) of the engine performed by the first control unit U1 is performed as described below. In Q4, transmission control for the second control unit U2 is performed as described later. Finally, in Q5,
The first control unit U1 performs a fault diagnosis related to the engine as a device to be controlled.

The contents of Q2 in FIG. 3 are shown in FIG. In Q11 of FIG. 4, it is determined whether or not a predetermined time has elapsed since the first control unit U1 was activated.
The predetermined time is set in consideration of the time required for performing the disconnection check, and is used to confirm whether the disconnection check has been completed. If the determination in Q11 is NO, in Q12, the warning lamp is checked for disconnection. This disconnection check is performed by, for example, performing control to temporarily turn on the warning lamp and turning on the warning lamp. This is performed by checking whether a predetermined change has occurred.

FIG. 5 shows the contents of Q3 in FIG. At Q15 in FIG. 5, various signals for engine control are read. Next, in Q16, control values required for engine control, such as the fuel injection amount and the ignition time, are calculated for the modes of the read various signals. Then, the control value calculated as described above is used as a control signal for various actuators for engine control (for example, a fuel injection valve or the like).
Is output to

FIG. 6 shows the contents of Q4 in FIG. In Q20 of FIG. 6, various signals input to the first control unit U1 and various control signals output from the first control unit U1 are transmitted from the first control unit U1 to the second control unit U2. You.

The contents of Q5 in FIG. 3 are shown in FIG. In Q21 in FIG. 7, failure diagnosis is performed based on various signals input to the first control unit U1 and various control signals output from the first control unit U1. In Q22, it is determined whether or not the possibility of failure is equal to or greater than a predetermined value. If the determination in Q22 is YES, the warning lamp is turned on, and the fact that the warning lamp is turned on, that is, the occurrence of the event is transmitted to the second control unit U2. The transmission of the occurrence of the event to the second control unit U2 includes a failure code indicating the content of the failure.

FIG. 8 shows an outline of the overall control of the second control unit U2. In Q31 of FIG. 8, it is determined whether or not there is a storage start command. In the embodiment, the storage is started when the IG switch is ON, and the IG switch is ON in Q31. It is determined whether or not. If the determination in Q31 is YES, in Q32, the memories M1, M2
, That is, sensor detection values such as the engine speed and the throttle opening.

If NO in Q31, it is determined in Q33 whether or not there is a command to transfer the data stored in the memories M1 and M2 to the outside of the vehicle. This transfer command is issued when performing an analysis based on the stored data or the like. Whether the transfer command switch included in the switch group 15 is turned on or whether a transfer device (tester / reader) is connected is determined. Will be determined. If the determination in Q33 is YES, in Q34, the data stored in the memories M1 and M2 is transferred out of the vehicle as described later. If the determination in Q33 is NO, the process returns.

The contents of Q32 in FIG. 8 are shown in FIG.
Explaining briefly the example shown in FIG. 9, when no event occurs, data including the sensor detection value is updated and stored in both memories M1 and M2 after addressing. That is, the oldest data in the set storage capacity range is deleted, while the newest data is written and stored so that changes in the stored data over a predetermined time range can be recognized. The stored time range is preferably as long as possible, and is set to range from several minutes to tens of minutes, depending on the memory capacity.

When the first event occurs, information outside the vehicle is obtained, and the obtained information outside the vehicle is stored in the first memory M1.
After the address has been specified and stored, the writing to the first memory M1 is prohibited (the stored data is stored to analyze the cause of the event occurrence later).

After the first occurrence of an event, data such as a sensor detection value is updated and stored after addressing in the second memory M2. When the second event occurs, the outside-of-vehicle information is obtained, and the obtained outside-of-vehicle information is stored in the second memory M.
After the address has been specified and stored in the second memory M2 only, writing to the second memory M2 is prohibited (the stored data is saved to analyze the cause of the event occurrence later). When the writing to the second memory M2 is performed by the occurrence of the second event, the control ends.

Assuming the above, in Q41 of FIG. 9, whether the warning lamp has been turned on twice (except for lighting for the check of disconnection) or not,
It is determined whether or not a failure has been detected. This determination is a determination as to whether or not an event has occurred twice. If the determination in Q41 is NO, in Q42, it is determined whether the warning lamp has been turned on once (excluding the lighting for the disconnection check) or whether a failure has been detected once. Is determined, which is to determine whether or not the event has occurred once.

If the determination in Q42 is NO, it means that no event has occurred, and this time is when the data values such as sensor detection values are updated and stored.
That is, control is performed such that data values are addressed and stored while replacing old data values with new data values within the range of the memory capacity.

The storage of data values such as sensor detection values differs depending on the processing load on the data writing control unit 21, especially the processing load on the DPRAM 23. That is, Q42
If the determination is YES, in Q43, the control unit 21
It is determined whether or not the processing load is equal to or higher than a predetermined level. If the determination in Q43 is NO, in Q44, in addition to the vehicle state, the type of sensor detection value, and various input signals and output signals received in response to the failure occurrence prediction, the addresses are designated in both memories M1 and M2. Then, it is updated and stored. When the determination in Q43 is YES, in addition to the engine speed and the vehicle speed, which particularly indicate the vehicle state, the type of the sensor detection value, and the various input signals and output signals received in response to the failure occurrence prediction, each is decimated. In a state where each data amount is reduced (in a state where the number of data per unit time is reduced), both the memories M1 and M2 are updated and stored after being addressed.

If the determination in Q42 is YES, Q4
In 6, it is determined whether or not it is immediately after lighting of a warning lamp or detection of a failure. If the determination in Q46 is YES, in Q47, outside-vehicle information is obtained as described later. Next, in Q48, the obtained outside-of-vehicle information is stored in the first memory M1 after addressing it in correspondence with the sensor detection value, and is written into the first memory M1 after storing in the outside-of-vehicle information. Is forbidden.

After Q48 or when NO is determined in Q46, it is determined in Q49 whether or not the processing load on the control unit 21 is equal to or higher than a predetermined level. This Q
If the determination in step 49 is NO, the various data are updated and stored after being specified in the memory without being thinned out (Q
If the answer is YES in the determination of Q49, the data is updated and stored after specifying the address in the memory while the data is decimated (corresponding to Q45). However, Q50, Q5
1, the only memory to be updated and stored is the second memory M2 (writing to the first memory M1 is performed in Q48).
Banned in).

If the determination in Q41 is YES, it means that the event has already occurred twice, and in this case,
In Q52, it is determined whether or not it is immediately after lighting of a warning lamp or detection of a failure. If the determination in Q52 is YES, in Q53, outside-vehicle information is obtained as described below (corresponding to Q47). Then, Q5
In 4, the acquired outside-of-vehicle information is stored in the second memory M2 after addressing it in correspondence with the sensor detection value, and after storing in the outside-of-vehicle information,
Writing to is prohibited. If NO in Q52, the process returns. FIG. 9 is based on the premise that the warning lamp is turned on or the failure is detected twice or less. When the warning lamp is turned on or the failure is detected three or more times, the update storage in the memory is not performed.

FIG. 10 shows the contents of Q47 and Q53 in FIG. In Q61 of FIG. 10, the connection is made to the information center 2 via the Internet, for example.
In Q62, the current position of the vehicle V, the type of desired outside-of-vehicle information, and the outline of the occurrence event are transmitted to the information center 2.
In Q63, the data received from the information center 2 is temporarily stored for later writing to the memories M1 and M2.

FIG. 11 shows an information center 2 corresponding to FIG.
2 shows the contents of control on the side. In Q65 of FIG. 11, after the content transmitted from the vehicle V is received, Q
At 66, data according to the request from the vehicle V is selected. Then, in Q67, the selected data is returned to the vehicle V.

FIG. 12 shows the contents of Q34 in FIG. In Q71 of FIG. 12, it is determined whether one or more warning lamps have been turned on or a failure has been detected before. If the determination in Q71 is NO,
It is terminated as it is.

If the determination in Q71 is YES, in Q72, the contents stored in the second memory M2 are read out by specifying the address. This reading is performed in the second control unit U.
This is performed by copying data to a tester / reader outside the vehicle connected to 2 or displaying the data on a display screen (not shown).

After Q73, in Q74, it is determined whether or not there is a second data transfer command. If the determination in Q74 is YES, in Q75, it is determined whether two warning lamps have been turned on or a failure has been detected previously. If the determination in Q75 is YES, Q
At 76, it is determined whether or not the contents stored in the second memory M2 have already been transferred. In the determination of Q76, YE
In the case of S, in Q77, the contents stored in the first memory M1 are transferred via the second memory M2 (corresponding to Q73). In the embodiment, the data cannot be directly transferred from the first memory M1 to the outside.
The contents stored in the first memory M1 are transferred to the outside of the vehicle via the memory M2.

FIG. 13 shows a modification of FIG. 9. Only the differences from FIG. 9 will be described below. First, in Q83 corresponding to Q43, it is determined whether the failure occurrence prediction, that is, the degree of certainty of the failure occurrence is equal to or higher than a predetermined level. If the determination in Q83 is YES, the data is thinned out in Q85 and updated and stored (same as Q45 in FIG. 9), and if the determination in Q83 is NO, the data is updated and stored without thinning out in Q84. (Same as Q44 in FIG. 9). Further, Q89 in FIG. 13 corresponds to Q49 to Q51 in FIG. That is, in the example of FIG. 13, writing of data to the second memory M2 immediately after the occurrence of the first event is performed without thinning regardless of the processing load on the control unit 21.

Here, of the above-mentioned control, a method of storing data in the memory will be supplementarily described with reference to FIG. 14 and subsequent figures. First, FIG. 14 corresponds to the example of FIG. 9, in which the data values including the sensor detection values are updated and stored in both memories M1 and M2.
After storing the acquired outside-of-vehicle information in the memory M1, it is time to perform a process of prohibiting writing to the first memory M1. FIG. 14 shows a process in which the data value is updated and stored in the second memory M2 without occurrence of the second event after occurrence of the first event. Of course, when the second event occurs, the information outside the vehicle is obtained, the obtained information outside the vehicle is stored in the second memory M2, and then the writing to the second memory M2 is prohibited.

The example of FIG. 15 shows a case where the data value including the sensor detection value is initially updated and stored only in the first memory M1. In FIG. 15, when the first event occurs, the information outside the vehicle is obtained, and after the information outside the vehicle is stored in the first memory M1, writing to the first memory M1 is prohibited.
After that, the update storage of the sensor detection value in the sensor M2 is started in the second memory M2, but the stored sensor detection value is only a part selected according to the content of the first event. . In other words, as the data to be updated and stored in the second memory M2, data irrelevant to the first occurrence event is omitted. Due to the second occurrence of the event, writing to the second memory M2 is also prohibited.

In the example of FIG. 16, the update storage in either the first memory M1 or the second memory M2 is performed by thinning out data values such as sensor detection values (sensor detection values and the like). Are updated and stored, for example, only one of the three sampled data values is sampled three times). This thinning may be performed only in the update storage before the first event occurrence, or may be performed only in the update storage after the first event occurrence, and the thinning is always performed. You can also. Further, as the memory to be updated and stored by being decimated, only the first memory M1, only the second memory M2, or both memories M1,
M2.

It should be noted that it is also possible to thin out only some data values without thinning out all data values such as sensor detection values. For example, when the engine speed is high, if all the engine speeds obtained in the sampling period for each rotation are updated and stored, the number of data to be stored becomes too large, so it is preferable to perform thinning. In addition, it is possible to always thin out data values that do not change rapidly in a short time, such as the temperature of the engine cooling water.

In the example shown in FIG. 17, as in the case of FIG. 14, it is assumed that update storage is performed in both memories M1 and M2 until the first event occurs, and the first memory M1 The update storage to only one of the second memories M2 is performed only for some of the data values such as the sensor detection value. As such a memory for updating and storing only some of the data values, the second memory M2 which is write-protected when the second event occurs
(Since the type of related data is limited by the occurrence of the first event).

In the example shown in FIG. 18, as in FIG. 14, update storage is performed on both memories M1 and M until the first event occurs.
2 is performed. When the data value is updated and stored in the first memory M1, the change of the thinning rate according to various data value signals and the change of the distribution rate according to the failure code signal are performed. The change in the thinning rate is a change in the degree of the thinning described above. The distribution ratio can be indicated by, for example, a ratio between the number of data of the cooling water temperature and the number of data of the engine rotation speed.
For example, it means that the distribution ratio is changed from 30% to 20%. The fact that the number of data of a certain data value is smaller than the number of data of other data values means that the ratio of a certain data value involved in the occurrence of an event is small. Note that only one of the change of the distribution rate and the change of the thinning rate may be performed, and such a change is performed not only in the first memory M1 but also in the second memory M2. And the second memory M2
Can be performed only for

Although the embodiment has been described above, the present invention is not limited to this, and includes, for example, the following cases. The devices to be subjected to failure detection and the like are not limited to engines, but may be any suitable devices such as automatic transmissions, suspension devices, air conditioners, and the like, and may be failure detection for several types of devices. The types of the memories M1 and M2 are not particularly limited. For example, both memories may be nonvolatile, and both memories M1 and M2 may be non-volatile.
It is also possible to use an SRAM having excellent responsiveness for both 1 and M2.
It is preferable to maintain the storage by a backup power supply so that the storage can be maintained even when the G switch is turned off).

The number of memories can be three or more (corresponding to the third or more occurrence of an event). In this case, the first memory M1
And the relationship between the second memory M2 and the second memory M2 are set as in the above-described embodiment.
What is necessary is just to correspond to the corresponding relationship between the first memory M1 and the second memory M2 (the same applies to the fourth memory and the following). Each step or various members such as a sensor and a switch shown in the flowchart can be expressed by adding a name of a means to a higher-level expression of its function. In addition, the object of the present invention is not limited to what is explicitly specified, but also implicitly includes providing what is expressed as substantially preferable or advantageous. Further, the present invention can be expressed as a storage control method.

[Brief description of the drawings]

FIG. 1 is a control system diagram showing one embodiment of the present invention.

FIG. 2 is a system diagram showing an example of obtaining information outside the vehicle.

FIG. 3 is a flowchart showing control contents of a first control unit that controls a device that is a target of event occurrence.

FIG. 4 is a flowchart showing details of control contents of FIG. 3;

FIG. 5 is a flowchart showing details of control contents of FIG. 3;

FIG. 6 is a flowchart showing details of control contents of FIG. 3;

FIG. 7 is a flowchart showing details of control contents of FIG. 3;

FIG. 8 is a diagram illustrating a second example of performing the storage control of the sensor detection value and the information outside the vehicle.
5 is a flowchart showing the control contents of the control unit.

FIG. 9 is a flowchart showing details of the control contents of FIG. 8;

FIG. 10 is a flowchart showing details of the control contents of FIG. 9;

FIG. 11 is a flowchart showing a control example of an outside-vehicle information transmission center corresponding to the control contents of FIG. 10;

FIG. 12 is a flowchart showing details of the control contents of FIG. 8;

FIG. 13 is a flowchart showing a modification of FIG. 9;

FIG. 14 is a diagram for explaining a storage method in two memories.

FIG. 15 is a diagram for explaining a method of storing data in two memories.

FIG. 16 is a diagram for explaining a storage method in two memories.

FIG. 17 is a view for explaining a method of storing data in two memories.

FIG. 18 is a view for explaining a method of storing data in two memories.

[Explanation of symbols]

1: Mobile phone (for obtaining information outside the vehicle) 2: Information transmission center outside the vehicle V: Vehicle U1: First control unit (for controlling devices such as engines) U2: Second control unit (for storing and controlling sensor detection values, etc.) U3 : Third control unit (for obtaining information outside the vehicle) 17: Transfer unit (for reading stored data) 21: Data writing control unit M1: First memory M2: Second memory

Claims (6)

[Claims] 1. A vehicle comprising a storage control means for constantly storing a sensor detection value in an address designated area of a memory and prohibiting writing to the memory when a preset event occurs or thereafter. A data storage device, wherein at least two memories, a first memory and a second memory, are provided as the memory, and the storage control unit is configured to control the first memory when the event does not occur.
After the address is specified for both the memory and the second memory, the sensor detection value is updated and stored, and when the first event occurs, writing to the first memory is inhibited and the subsequent sensor detection is performed. A data storage device for a vehicle, wherein a value is updated and stored after addressing only in a second memory, and writing to the second memory is also prohibited when a second event occurs. 2. A vehicular data storage device comprising storage control means for storing a sensor detection value in an address designated area of a memory when a preset event occurs, wherein said memory includes at least a first memory and a first memory. Two memories are provided, and the storage control means is configured to control the first memory when the event does not occur.
The sensor detection value is updated and stored in the memory only after the address is specified, writing to the first memory is prohibited at the time of the first occurrence of the event, and the subsequent sensor detection value is generated at the first occurrence. The second is selected according to the event.
A data storage device for a vehicle, wherein an address is stored in a memory after the address is specified, and writing of the second memory is also prohibited when a second event occurs. 3. The storage control unit according to claim 1, wherein the storage control unit stores the update storage when no event occurs, and stores the sensor detection value in at least one of the first memory and the second memory. A data storage device for a vehicle, wherein the data storage device is thinned out. 4. The storage control device according to claim 3, wherein the storage control means updates and stores only a part of the sensor detection values in one of the first memory and the second memory. A vehicle data storage device characterized by the above-mentioned. 5. The storage control unit according to claim 3, wherein the storage control means includes: a vehicle state; a type of a sensor detection value;
A method of storing data for a vehicle, wherein the storage method is changed so that the number of data to be updated and stored is changed in accordance with at least one of the content of the generated event and the processing load of the storage control means. apparatus. 6. The method according to claim 1, wherein only one of the first memory and the second memory includes:
Storage data reading means connected thereto, wherein the storage control means causes the storage data to be fetched from a memory to which the reading means is not connected, via a memory to which the reading means is connected. A vehicle data storage device characterized by the above-mentioned.