JP2013242828A - Data consistency guarantee system - Google Patents

Abstract

A data integrity guarantee system capable of guaranteeing the integrity of data used for calculation of a plurality of data reference S / Ws.
Data used by a data reference S / W1, 2, and 3 is stored in a calculation data storage buffer 41. The calculation data storage buffer 41 is used for calculation by a data reference S / W1, 2, and 3. A data reference presence / absence recording area 411 for recording the presence / absence of reference to the data storage buffer 41 is provided, and the buffer management S / W 4 stores the latest data in the data storage buffer 41 for calculation according to the recording in the data reference presence / absence recording area 411. In response to the data reference request from the storage and data reference S / W 1, 2, 3, the reference instruction of the operation data storage buffer 41 and the update of the data reference presence / absence recording area 411 are performed, and the data reference presence / absence recording area 411 is updated. However, when all the data references S / W have already been referenced, all the data references S / W are made unreferenced.
[Selection] Figure 1

Description

  The present invention relates to a data integrity assurance system that provides data integrity assurance for a plurality of data reference S / Ws (software).

Recent automobiles realize advanced control by using information obtained from various sensors. For example, in vehicle integrated control, the behavior of a vehicle is estimated based on information such as vehicle speed / acceleration / yaw rate / steering angle / accelerator opening, and the anti-lock brake system (hereinafter referred to as ABS) is applied in a direction to stabilize the vehicle behavior. ), Traction control system (hereinafter TCS), and electric power steering (hereinafter EPS).
In vehicle integrated control, ABS, TCS, and EPS control software (S / W) is considered as one of the components of a system that controls vehicle behavior in an integrated manner, and each control S / W controls each independently. Instead of integrated control.
Further, there is a vehicle speed as data commonly used by each control S / W of ABS, TCS, and EPS. If each control S / W uses vehicle speed data that is not updated at the same timing, the behavior of the entire vehicle becomes unstable. Therefore, it is important for each control S / W to perform calculations based on data updated at the same timing, that is, data with guaranteed consistency.
In addition, in data that can be acquired in time series such as vehicle speed data, the greater the number of data that can guarantee consistency, the shorter the control cycle of the control S / W that is calculated using it, and smoother It is possible to control the behavior of the vehicle.

In Patent Document 1, the execution priority of processing is set in each of S / W (data reference S / W) for performing some calculation with reference to data and S / W (data disclosure S / W) for releasing data. Has been.
The data disclosure S / W has two types of data to be provided to the data reference S / W: public data and storage data. The latest data is stored in the public data, and data that guarantees consistency is stored in the stored data.
When the data reference S / W makes a reference request, the data disclosure S / W compares the execution priority of the data reference S / W with the execution priority of the data reference S / W, thereby determining the reference destination of the data reference S / W. Switch to public data or stored data.
For the data reference S / W that performs arithmetic processing based on data with guaranteed consistency, the execution priority is set lower than the data disclosure S / W, thereby ensuring data consistency. .

Japanese Patent Laying-Open No. 2011-170626 (pages 5-9, FIG. 1)

  The ideal activation order of the data update processing by the data disclosure S / W and the calculation processing of a plurality of data reference S / Ws is to be stored by the data disclosure S / W after all the data reference S / W processing is completed. This is the activation order for performing data update processing (see FIG. 2 described later). Under such conditions, the data consistency can be sufficiently guaranteed by using the data consistency guarantee method described in Patent Document 1.

However, the update process of data and the calculation process of a plurality of data reference S / Ws are not necessarily performed in an ideal order.
As an example, data update processing is delayed between the data reference S / W1 and the data reference S / W2 in the R + 1 cycle as a result of data update processing being delayed due to other S / W interrupt processing or the like. If entered (see FIG. 3 to be described later), the data reference S / W1 uses the stored data N, and the data reference S / W2 and the data reference S / W3 use the stored data N + 1 because the update process has been inserted. Since the calculation is performed, the consistency of data used for the calculation in the R + 1 cycle cannot be guaranteed.

In addition, in a system configured with multitask / multithread / multicore, etc., if the processing in which the activation order of a plurality of data reference S / Ws is not the same every time, other S / W interrupt processing, etc. As a result, the activation order of the data reference S / W is changed, and the same data reference S / W may be activated a plurality of times until one cycle of processing is completed (see FIG. 7 described later).
For example, the activation order of the data reference S / W3 in the R cycle and the data reference S / W1 in the R + 1 cycle are switched, and the data reference S / W1 becomes 2 before the processing of the data reference S / W in the R cycle is completed. If the number of data that can guarantee the consistency is only one when the activation is performed once, the data reference S / W3 in the R cycle can only refer to the data N + 1. The consistency of the data used for the calculation is lost.
Therefore, when the number of data that can guarantee the consistency is only one, when the start order of the data reference S / W is changed, the data used by the replaced data reference S / W for the calculation is matched. Sex cannot be guaranteed.
When the same phenomenon occurs in the vehicle integrated control, the result of each control S / W calculated based on the data whose consistency is not guaranteed cannot be used for the control. There is a problem that the timing becomes irregular and the behavior of the vehicle becomes unstable.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a data integrity guarantee system that can guarantee the integrity of data used to calculate a plurality of data reference S / Ws. Yes.

  In the data integrity guarantee system according to the present invention, a plurality of data reference means for performing calculations using data respectively, data used for the calculations by the data reference means are stored, and whether data is referenced by the data reference means is recorded. A storage buffer having a data reference presence / absence recording area, and buffer management means for managing storage of data in the storage buffer and reference by the data reference means for the stored data. In the data reference presence / absence recording area, when all data reference means are unreferenced, new data is stored in the storage buffer, and when the data reference means requests reference to data stored in the storage buffer, data reference presence / absence recording is performed. If the data reference means is unreferenced in the area, the data reference means In addition, the reference of the data in the storage buffer is instructed, the reference by the data reference means is recorded in the data reference presence / absence recording area, and the data reference presence / absence recording area of the storage buffer is already referenced by all the data reference means In this case, all data reference means unreference the data reference presence / absence recording area of the storage buffer.

  According to this invention, the data reference presence / absence recording area for storing a plurality of data reference means for performing calculations using data, storing data used for the calculation by the data reference means, and recording the presence / absence of data reference by the data reference means And a buffer management means for managing storage of data in the storage buffer and reference by the data reference means for the stored data, the buffer management means including a data reference presence / absence recording area of the storage buffer When all the data reference means are unreferenced, new data is stored in the storage buffer. When the data reference means requests reference to the data stored in the storage buffer, the data reference means is stored in the data reference presence / absence recording area. Is not referenced, the data reference means is referred to the data in the storage buffer. When the reference by the data reference means is recorded in the data reference presence / absence recording area and the data reference presence / absence recording area of the storage buffer is already referenced by all the data reference means, the data reference presence / absence recording of the storage buffer is recorded. Since all data reference means make the area unreferenced, new data is stored in the storage buffer at the timing when the data consistency is not lost, and the consistency of data used by multiple data reference means is guaranteed. Can do.

It is the schematic which shows the system configuration | structure of the vehicle integrated control system by Embodiment 1 of this invention. It is a figure which shows the calculation process order of the ideal data update process and several data reference S / W in a vehicle integrated control system. It is a figure which shows the calculation processing order of data reference S / W in the operation example 1 of the vehicle integrated control system by Embodiment 1 of this invention. It is a flowchart which shows the flow of a buffer management S / W process of the vehicle integrated control system by Embodiment 1 of this invention. It is a flowchart which shows the flow of each S / W process of the vehicle integrated control system by Embodiment 1 of this invention. It is the schematic which shows the system configuration | structure of the vehicle integrated control system by Embodiment 2 of this invention. It is a figure which shows the calculation processing order of data reference S / W in the operation example 2 of the vehicle integrated control system by Embodiment 2 of this invention. It is a flowchart which shows the flow of a process of buffer management S / W of the vehicle integrated control system by Embodiment 2 of this invention. It is a flowchart which shows the flow of each S / W process of the vehicle integrated control system by Embodiment 2 of this invention. It is a figure which shows the calculation processing order of data reference S / W in the operation example 3 of the vehicle integrated control system by Embodiment 2 of this invention. It is a flowchart which shows the flow of each S / W process when the data consistency in the operation example 3 of the vehicle integrated control system by Embodiment 2 of this invention cannot be guaranteed. It is a figure explaining the shift | offset | difference of starting timing of data reference S / W in the operation example 4 of the vehicle integrated control system by Embodiment 2 of this invention. It is a figure explaining the adjustment of the starting timing of data reference S / W in the operation example 4 of the vehicle integrated control system by Embodiment 2 of this invention.

Embodiment 1 FIG.
<Configuration>
Hereinafter, a vehicle integrated control system (data consistency guarantee system) for controlling the vehicle behavior in a direction to stabilize the vehicle according to the first embodiment will be described.
1 is a schematic diagram showing a system configuration of a vehicle integrated control system according to Embodiment 1 of the present invention.
In FIG. 1, the vehicle integrated control system includes data references S / W1 to 3 (data reference means) that calculate using data, and data storage for calculation that stores data used by the data references S / W1 to S3. The buffer 41 (storage buffer) and the buffer management S / W 4 (buffer management means) for managing the calculation data storage buffer 41 are configured. These data references S / W 1 to 3 and the buffer management S / W 4 are computers. It is executed by.
The calculation data storage buffer 41 has a data reference presence / absence recording area 411 which is an area for recording the reference presence / absence information of the data references S / W1 to S3-3.
The data reference S / W1 is an ABS control S / W. The data reference S / W2 is a TCS control S / W. The data reference S / W3 is an EPS control S / W.
The buffer management S / W 4 refers to the calculation data storage buffer 41 with respect to the data reference S / W based on the information recorded in the data reference presence / absence recording area 411 in response to the data reference request of the data reference S / W. The reference presence / absence information recorded in the data reference presence / absence recording area 411 is updated.
Here, for simplification of explanation, it is assumed that the data handled is only vehicle speed data. This is because only the vehicle speed data is commonly used in all of the ABS control S / W, the TCS control S / W, and the EPS control S / W. An operation example of each data reference S / W will be described later.

FIG. 2 is a diagram showing an ideal data update process and a calculation process order of a plurality of data reference S / Ws in the vehicle integrated control system.
In FIG. 2, as the R cycle, in steps S201, S301, and S401, the data reference S / W1, the data reference S / W2, and the data reference S / W3 are activated, and after the data reference, the buffer management is performed in step S501. The S / W 4 acquires the latest data N + 1, and then, in the R + 1 cycle, in steps S202, S302, and S402, the data reference S / W1, the data reference S / W2, and the data reference S / W3 are activated, respectively. After the reference, in step S502, the buffer management S / W4 acquires the latest data N + 2, and then in steps S203, S303, and S403, the data reference S / W1, the data reference S / W2, and the data reference S / W3 are obtained. Each is activated and references data.

FIG. 3 is a diagram showing the calculation processing order of the data reference S / W in the operation example 1 of the vehicle integrated control system according to the first embodiment of the present invention.
In FIG. 3, the latest data N + 1 acquisition in step S511 is after the start of the data reference S / W1. Details will be described later.

Next, the operation will be described.
When no data reference S / W has been referred to the data reference presence / absence recording area 411 of the calculation data storage buffer 41, the buffer management S / W 4 stores the acquired latest data in the calculation data storage buffer 41. If at least one data reference S / W already referenced exists in the data reference presence / absence recording area of the calculation data storage buffer 41, the latest data is not stored in the calculation data storage buffer 41.
If the latest data acquisition cycle is slow, the latest data is temporarily stored in another storage buffer, and the latest data stored in another storage buffer is stored at a timing that does not destroy the integrity of the data. It may be copied to the calculation data storage buffer 41.

Further, the buffer management S / W 4 stores the data reference S / W that has issued a reference request in the calculation data storage buffer 41 based on the information in the data reference presence / absence recording area 411 of the calculation data storage buffer 41. Permission / disapproval of reference to the recorded data is issued.
Then, the data reference S / W that has been referred to is recorded in the data reference presence / absence recording area 411.
Further, when all the data references S / W refer to the data stored in the operation data storage buffer 41, the buffer management S / W 4 does not refer to all the data reference presence / absence recording areas 411 of the operation data storage buffer 41. To.

<Processing flow>
Next, the flow of processing of the buffer management S / W 4 will be described using the flowchart of FIG.
The buffer management S / W4 is activated by acquisition of the latest data, a reference request for the data reference S / W1 to S3, or by periodic activation. In the first embodiment, a description will be given of a case where activation is performed by acquisition of the latest data or a reference request for data reference S / W.
First, the buffer management S / W 4 confirms whether the latest data acquisition or the data reference S / W reference request is activated (S1011). If the latest data is acquired, the process proceeds to step S1012. If the data reference S / W is requested, the process proceeds to step S1014.

In step S1012, it is determined whether or not all the data reference presence / absence recording areas 411 of the calculation data storage buffer 41 are unreferenced. When all the data reference presence / absence recording areas 411 are unreferenced, it means that there is no data reference S / W referring to the data stored in the calculation data storage buffer 41 or the calculation data storage buffer. Since the data stored in 41 is referred to by all the data references S / W, this means that the data reference presence / absence recording area 411 has been reset.
Therefore, since there is no data reference S / W that requires data currently stored in the calculation data storage buffer 41, the latest data is stored in the calculation data storage buffer 41 (S1013). After the storage or when any data reference S / W has been referred to, the buffer management S / W4 process is terminated.

  In step S1014, it is determined whether or not the data reference S / W requesting the reference has already referred to the calculation data storage buffer 41. If the reference has not been made, the data reference S / W requesting the reference is instructed to refer to the operation data storage buffer 41, and the data reference presence / absence recording area 411 of the data reference S / W that has requested the reference. Is changed to “referenced” (S1015). After the change or when the reference has been made, the process proceeds to step S1016.

In step S1016, it is determined whether all the data reference presence / absence recording areas 411 of the calculation data storage buffer 41 have been referred to. When all of the data has been referred to, the data stored in the operation data storage buffer 41 is referred to by all the data references S / W1 to S3, so that it is not necessary to store the data.
Therefore, in order to reset the data reference presence / absence recording area 411, all the data reference presence / absence recording areas 411 of the calculation data storage buffer 41 are changed to unreferenced (S1017). If not all references have been made, it is necessary to store the data in the operation data storage buffer 41 until the reference to the unreferenced data reference S / W is completed. Terminate the process.

<Operation example 1>
An operation example 1 will be described as a specific operation example with reference to FIGS. 1, 3, and 5.
The buffer management S / W 4 in FIG. 1 stores the reference presence / absence information of the data reference S / W 1, the data reference S / W 2, and the data reference S / W 3 recorded in the data reference presence / absence recording area 411 of the calculation data storage buffer 41. Based on this, the acquired latest data is stored in the calculation data storage buffer 41 at a timing that does not destroy the consistency of the data stored in the calculation data storage buffer 41.
The data reference S / W1, the data reference S / W2, and the data reference S / W3 perform arithmetic processing by referring to the vehicle speed data stored in the arithmetic data storage buffer 41 managed by the buffer management S / W4.

First, initial conditions in this operation example 1 will be described.
The data reference S / W1, the data reference S / W2, and the data reference S / W3 access the calculation data storage buffer 41 managed by the buffer management S / W4 with the vehicle speed data necessary for performing the calculation process. Get by. The data reference S / W1, the data reference S / W2, and the data reference S / W3 are independent S / Ws, and do not directly interfere with the activation order and the activation cycle.

Next, the activation order of the data reference S / W1, the data reference S / W2, and the data reference S / W3 will be described. In the first embodiment, the case of starting in the order of data reference S / W1, data reference S / W2, and data reference S / W3 is set as an ideal start order. Also in the first embodiment, each data reference S / W is activated in the order shown in FIG. Further, as shown in FIG. 3, a state in which the calculation processing of all the data reference S / Ws is completed using the same vehicle speed data is defined as one cycle.
In FIG. 3, the data reference S / W is sequentially activated in the same activation order as in FIG. 2, but the latest data acquisition timing is different from that in FIG.

The description of the operation example 1 starts from step S212 in which the data reference S / W1 in the R + 1 cycle in FIG. 3 is activated. The situation of the calculation data storage buffer 41 at this time is B101 in FIG.
First, the data reference S / W1 is activated and requests data reference to the buffer management S / W4 (step S212 in FIG. 3). The buffer management S / W4 activated by the reference request for the data reference S / W1 determines whether or not the data reference S / W1 is referred to the calculation data storage buffer 41 based on the data reference presence / absence recording area 411 (step S1014 in FIG. 4). ).
Since the data reference presence / absence recording area 411 in B101 in FIG. 5 is not referenced, the buffer management S / W4 instructs the data reference S / W1 to refer to the calculation data storage buffer 41. After recording that the data reference S / W1 has referred to the data reference presence / absence recording area 411 of the calculation data storage buffer 41 (step S1015 in FIG. 4), the data reference S / W1 is calculated using the acquired data N. Process.
Since the state of the storage buffer after step S212 in FIG. 3 is B102 in FIG. 5, when the process proceeds to step S1016 in FIG. 3, the data reference by the data reference S / W2 and the data reference S / W3 is not completed. The buffer management S / W4 ends the process.

Here, it is assumed that the latest vehicle speed data (data N + 1) is provided (step S511 in FIG. 3). The buffer management S / W 4 activated by acquiring the latest data determines whether or not to store the acquired latest data in the calculation data storage buffer 41 (step S1012 in FIG. 4).
Looking at the data reference presence / absence recording area 411 of B102 in FIG. 5, it can be seen that the data reference S / W2 and the data reference S / W3 have not completed the reference to the data N. Therefore, if the data N + 1 is stored in the calculation data storage buffer 41 at this time, the data reference S / W in the R + 1 cycle loses the consistency of the data used for the calculation, so the latest data N + 1 is calculated. The data is not stored in the data storage buffer 41 but discarded, and the buffer management S / W 4 ends the process.
The state of the operation data storage buffer after step S212 in FIG. 3 is B103 in FIG.

Next, the data reference S / W2 is activated and requests the buffer management S / W4 to refer to the data (step S312 in FIG. 3). The buffer management S / W4 activated by the reference request for the data reference S / W2 determines whether or not the data reference S / W2 is referred to the operation data storage buffer 41 based on the data reference presence / absence recording area 411 (step S1014 in FIG. 4). ).
From the data reference presence / absence recording area 411 of B103 in FIG. 5, it can be seen that the data reference S / W2 does not refer to the calculation data storage buffer 41. Therefore, the buffer management S / W 4 instructs the data reference S / W 2 to refer to the calculation data storage buffer 41, and the data reference S / W 2 is stored in the data reference presence / absence recording area 411 of the calculation data storage buffer 41. After recording the reference (step S1015 in FIG. 4), the data reference S / W2 performs an arithmetic process using the acquired data N.
Since the status of the storage buffer after step S312 in FIG. 3 is B104 in FIG. 5, when the process proceeds to step S1016 in FIG. 3, the data reference by the data reference S / W3 has not been completed, so the buffer management S / W4 Ends the process.

Subsequently, the data reference S / W3 is activated and requests the buffer management S / W4 to refer to the data (step S412 in FIG. 3). The buffer management S / W4 activated by the reference request for the data reference S / W3 determines whether or not the data reference S / W3 is referred to the calculation data storage buffer 41 based on the data reference presence / absence recording area 411 (step S1014 in FIG. 4). ).
Looking at the data reference presence / absence recording area 411 of B104 in FIG. 5, it can be seen that the data reference S / W3 does not refer to the calculation data storage buffer 41. Therefore, the buffer management S / W 4 instructs the data reference S / W 3 to refer to the calculation data storage buffer 41, and the data reference S / W 3 is stored in the data reference presence / absence recording area 411 of the calculation data storage buffer 41. After recording the reference (step S1015 in FIG. 4), the data reference S / W3 performs an arithmetic process using the acquired data N.
The state of the calculation data storage buffer 41 after step S412 in FIG. 3 is B105 in FIG.

At this time, when the data reference presence / absence recording area 411 of B105 in FIG. 5 is seen, it can be seen that the data N stored in the calculation data storage buffer 41 is referred to by all the data references S / W. Therefore, since it is not necessary to store the data N in the calculation data storage buffer 41, when the processing proceeds to step S1016 in FIG. 3, all the data reference presence / absence recording areas 411 of the calculation data storage buffer 41 are unreferenced (see FIG. 4 step S1017), the buffer management S / W4 ends the process.
The state of the calculation data storage buffer 41 after step S412 in FIG. 3 is B106 in FIG.

Thereafter, it is assumed that the latest data N + 2 is acquired (step S512 in FIG. 3). The buffer management S / W 4 activated by acquiring the latest data determines whether or not to store the acquired latest data in the calculation data storage buffer 41 (step S1012 in FIG. 4). Since all the data reference presence / absence recording areas 411 of the calculation data storage buffer 41 are unreferenced, the latest data N + 2 is stored in the calculation data storage buffer 41 (step S1013 in FIG. 4), and the buffer management S / W4 performs processing. finish.
The state of the storage buffer after step S512 in FIG. 3 is B107 in FIG.

<Effect in Operation Example 1 of Embodiment 1>
According to the operation example 1 of the first embodiment, the presence / absence of reference to the calculation data storage buffer 41 of the data reference S / W is recorded, and the calculation data storage buffer 41 for new data at the timing when the data consistency is lost. By preventing the data from being stored in the data, it is possible to guarantee the consistency of the data used by the plurality of data reference S / Ws in the calculation.

In addition, when the cycle in which the vehicle speed data can be acquired is longer than the activation cycle of the data reference S / W, the data reference S / W may be calculated again using data that has not been updated. Even if the calculation is performed again with the data once used, only the same calculation result is obtained, which is a wasteful calculation process.
In this case, useless arithmetic processing can be suppressed by adding another buffer to the system configuration of the first embodiment.
In a system in which another buffer is added, the acquired latest data is not stored directly in the operation data storage buffer 41 but is temporarily stored in a newly added buffer.
The buffer management S / W 4 stores the data stored in another buffer in the calculation data storage buffer 41 at a timing that does not destroy the consistency of the data stored in the calculation data storage buffer 41. It is possible to suppress unnecessary arithmetic processing while ensuring data consistency.

Embodiment 2. FIG.
<Configuration>
FIG. 6 is a schematic diagram showing a system configuration of a vehicle integrated control system according to Embodiment 2 of the present invention.
In FIG. 6, 1-4 are the same as those in FIG. In FIG. 6, a storage buffer 6, a storage buffer 7, and a storage buffer 8 for storing data used for calculation are provided, and each storage buffer 6, 7, and 8 records data reference presence / absence information by each data reference S / W. Data reference presence / absence recording areas 61, 71, 81 and data storage order recording areas 62, 72, 82 (storage order recording areas) for recording the data storage order for each storage buffer.
The buffer management S / W 4 acquires the data storage order recording areas 62, 72, 82 and the data reference presence / absence recording area 61 of each storage buffer 6, 7, 8 by acquiring the latest data or requesting data reference of each data reference S / W , 71 and 81, the information recorded is updated.
Further, the buffer management S / W 4 designates a storage buffer referred to by each data reference S / W based on the information of each storage buffer.

FIG. 7 is a diagram showing the calculation processing order of the data reference S / W in the operation example 2 of the vehicle integrated control system according to the second embodiment of the present invention.
In FIG. 7, the data reference S / W1 in the R + 1 cycle is activated prior to the activation of the data reference S / W3 in the R cycle, as in steps S222 and S421. Details will be described later.

FIG. 10 is a diagram showing the calculation processing order of the data reference S / W in the operation example 3 of the vehicle integrated control system according to the second embodiment of the present invention.
In FIG. 10, the data reference S / W is not activated in the order of the data reference S / W1, the data reference S / W2, and the data reference S / W3. Details will be described later.

FIG. 12 is a diagram for explaining a start timing shift of the data reference S / W in the operation example 4 of the vehicle integrated control system according to the second embodiment of the present invention.
In FIG. 12, the vertical axis represents the data reference S / W and the horizontal axis represents time, and the data reference S / W1, the data reference S / W2, and the data reference S / W3 have different activation intervals.

FIG. 13 is a diagram for explaining the adjustment of the activation timing of the data reference S / W in the operation example 4 of the vehicle integrated control system according to the second embodiment of the present invention.
In FIG. 13, the vertical axis represents the data reference S / W and the horizontal axis represents the time. The appropriate adjustment time is inserted into each of the data reference S / W2 and the data reference S / W3 with a short activation interval, The data reference S / W has the same activation interval.

Next, the operation will be described.
The buffer management S / W 4 determines the latest data based on the information in the data reference presence / absence recording areas 61, 71, 81 and the buffer storage order recording areas 62, 72, 82 at the timing of storing the latest data in the storage buffer. Store in the save buffer.
Here, the predetermined storage buffer refers to a storage buffer that satisfies any one condition such as storing the oldest data or not referring to any data reference S / W. After storing data in the storage buffer, the storage order recorded in the buffer storage order recording area of the storage buffer storing the data is updated.

Each data reference S / W refers to the storage buffer selected by the buffer management S / W 4 based on the information of the data reference presence / absence recording area and the buffer storage order recording area of each storage buffer. Then, the buffer management S / W 4 records the data reference S / W that has been referred to in the data reference presence / absence recording area of the selected storage buffer.
When there is a storage buffer in which all the data references S / W have been referred to, the buffer management S / W 4 makes all the data reference presence / absence recording areas of the storage buffer unreferenced.

According to this, for example, when a data reference S / W is activated twice in one cycle, the storage buffer referred to by the data reference S / W activated first time is stored in the data reference presence / absence recording area. Judging from the recorded information, the data reference S / W activated second time can refer to a storage buffer in which data different from the data referred to by the data reference S / W activated first time is stored.
That is, in a situation where the data used for the calculation of the data reference S / W has to be changed depending on the number of activations, the buffer management S / W 4 can provide different data for each of the data reference S / Ws. .

  As described above, when data is provided to the data reference S / W activated a plurality of times in one cycle, information on the presence / absence of the data reference S / W in each storage buffer and the storage order of the stored data are displayed. By using it, it is possible to provide data according to the number of activations of the data reference S / W while guaranteeing the consistency of data obtained at different timings.

As another situation, in a situation where one data reference S / W has already referred to all the storage buffers other than the storage buffer in which the latest data is stored, the buffer management S / W 4 has the data reference S / W. Is instructed to refer to the storage buffer in which the latest data is stored, all the storage buffers are already referred to by the data reference S / W.
In other words, the integrity of the stored data must be guaranteed in all the storage buffers. In this state, when newer data is acquired, the latest data is stored in one of the storage buffers, so that the data originally stored in the storage buffer is overwritten with the latest data.
Therefore, the buffer management S / W 4 cannot provide the data to the data reference S / W that has not yet referred to the originally stored data, and the data consistency is lost.
In such a case, when the data reference S / W requests the data reference in a situation where all the storage buffers in which data other than the latest data are stored have been referred to by one data reference S / W. The data reference S / W is not allowed to refer to the data.

  In this way, the presence / absence of reference to each storage buffer of the data reference S / W is recorded so as not to cause a situation in which the storage buffer in which data reference has not been completed by all the data reference S / Ws is overwritten with the latest data. Then, it is possible to guarantee the consistency of the data stored in the storage buffer by issuing reference permission / non-permission to the data reference S / W according to the status of the storage buffer.

<Processing flow>
Next, the flow of processing performed by the buffer management S / W 4 in FIG. 6 will be described with reference to the flowchart in FIG.
The buffer management S / W 4 in the second embodiment is activated by a reference request for the data reference S / W, or is activated periodically.

  First, it is confirmed whether or not there is a data reference request from the data reference S / W (S10201). If there is no data reference request, the process is terminated, and if there is a reference request, the reference presence / absence record information in the storage buffers 6 to 8 is confirmed (S10202). Based on the information in the reference presence / absence recording area, it is determined whether there is a data reference S / W referring to the storage buffer in which the latest data is stored (S10203). When it exists, it progresses to step S10204, and when it does not exist, it progresses to step S10207.

In step S10204, it is determined whether the data reference S / W referring to the storage buffer in which the latest data is stored is the data reference S / W that has requested data reference.
When the data reference S / W that refers to the storage buffer in which the latest data is stored is the data reference S / W that has requested data reference, the data reference S / W indicates that the data has not been updated. However, since it has been activated, the process ends without doing anything.
Conversely, if the data reference S / W that refers to the storage buffer in which the latest data is stored is not the data reference S / W that has requested data reference, the data reference S / W that has requested data reference. This means that there is a data reference S / W that has been activated earlier, and the process advances to step S10205 to select a storage buffer to be referred to.

  In step S10205, the storage buffer referred to by the data reference S / W that has requested data reference is selected. The oldest buffer is selected from among the buffers satisfying the condition that any data reference S / W has been referred to and the data reference S / W that has requested data reference has not been referred to. Then, the data reference presence / absence recording area of the selected storage buffer is changed to “referenced” (S10206). After the change, go to step S10210.

In step S10207, it is determined whether there is a storage buffer in which another data reference S / W has been referred to and the data reference S / W that has requested data reference has not been referenced.
If there is even one storage buffer that satisfies the condition of step S10207, the process proceeds to step S10205. If no buffer satisfies the condition, the process proceeds to step S10208.

  In step S10208, it is determined whether the data reference S / W that has requested the data reference has already referred to all the storage buffers other than the storage buffer in which the latest data is stored. If all the storage buffers other than the storage buffer storing the latest data have been referred to, the process proceeds to step S10210. If not, the process proceeds to step S10209.

  In step S10209, the data reference S / W requesting the reference is instructed to refer to the storage buffer in which the latest data is stored, and the data reference S is stored in the data reference presence / absence recording area of the storage buffer in which the latest data is stored. Record what / W referenced. Thereafter, the process proceeds to step S10210.

In step S10210, it is determined whether there is a storage buffer to which all data reference S / Ws have been referenced. If the data exists, the data stored in the corresponding storage buffer is referred to by all the data reference S / Ws, so that it is not necessary to store the data.
Therefore, in order to reset the data reference presence / absence recording area of the corresponding storage buffer, all the data reference presence / absence recording areas are unreferenced (S10211).

<Operation example 2>
Operation example 2 will be described as a specific operation example in the second embodiment with reference to FIGS.
Note that the initial conditions of Operation Example 2 are the same as the initial conditions of Operation Example 1.
However, the data reference S / W1, the data reference S / W2, and the data reference S / W3 are vehicle speed data necessary for performing the calculation process, and the buffer management S / W4 is a data reference presence / absence recording area 61, 71, 81. And the data storage order recording areas 62, 72, and 82 are obtained by accessing the storage buffer selected based on the information.
Further, when the latest data is acquired, the buffer management S / W 4 stores the latest data in the oldest storage buffer among the storage buffers that are not referenced by any data reference S / W at that time. If there is no storage buffer that does not refer to any data reference S / W, it is stored in the oldest storage buffer.

Next, the activation order of each data reference S / W will be described.
In the activation order of the operation example 2, the activation order of the data reference S / W is changed depending on the processing time of each data reference S / W, the interrupt processing time, and the other S / W processing time. Consider a case in which activation is not always performed in a specific order, and consider an activation order as shown in FIG.

  Furthermore, it is assumed that the buffer management S / W4 has acquired the latest vehicle speed data after the data reference S / W2 in the R cycle in FIG. 7 is activated.

The description of the operation example 2 starts from step S221 in which the data reference S / W1 in the R cycle in FIG. 7 is activated.
The status of each storage buffer at this time is B201 in FIG. The larger the numerical value stored in the data storage order recording area of FIG. 9, the newer the vehicle speed data.

First, the data reference S / W1 is activated and requests the buffer management S / W4 to refer to data (step S221 in FIG. 7). The buffer management S / W4 activated by the reference request for the data reference S / W1 confirms the information in the data storage order recording areas 62, 72, 82 and the data reference presence / absence recording areas 61, 71, 81 (step S10202 in FIG. 8). .
Looking at the data reference presence / absence recording area B201 in FIG. 9, there is no data reference S / W referenced in any storage buffer. 9 shows that the latest vehicle speed data is stored in the storage buffer 6. FIG.
Therefore, the buffer management S / W 4 instructs the data reference S / W 1 to refer to the storage buffer 6, and records that the data reference S / W 1 has referred to the data reference presence / absence recording area 61 of the storage buffer 6. (FIG. 8, step 10209). The data reference S / W1 performs arithmetic processing using the acquired data N.
The status of each storage buffer after step S221 in FIG. 7 is B202 in FIG.

Next, the data reference S / W2 is activated and requests the buffer management S / W4 to refer to the data (step S321 in FIG. 7). The buffer management S / W4 activated by the reference request for the data reference S / W2 confirms the information in the data storage order recording areas 62, 72, 82 and the data reference presence / absence recording areas 61, 71, 81 (step S10202 in FIG. 8). .
Looking at the data reference presence / absence recording area of B202 in FIG. 9, it can be seen that only the data reference S / W1 has been referred to in the storage buffer 6, and there is no data reference S / W referring to the storage buffer 7 and the storage buffer 8.
Therefore, the buffer management S / W 4 instructs to refer to the storage buffer 6 referred to by the previously activated data reference S / W 1 (step 10205 in FIG. 8), and data is stored in the data reference presence / absence recording area 61 of the storage buffer 6. Record that the reference S / W2 refers (step 10206 in FIG. 8). Thereafter, the data reference S / W2 performs arithmetic processing using the acquired data N.
The status of each storage buffer after step S321 in FIG. 7 is B203 in FIG.

Here, it is assumed that the latest vehicle speed data (data N + 1) is acquired (step S521 in FIG. 7).
In the second embodiment, when the latest data is acquired, it is assumed that it is stored in the oldest storage buffer among the storage buffers that do not refer to any data reference S / W at that time.
Looking at the data reference presence / absence recording area of B203 in FIG. 9, since data for which consistency must be guaranteed is stored in the storage buffer 6, it cannot be updated with the latest data. Regarding the storage buffer 7 and the storage buffer 8, since no data reference S / W is referred to, it is not data for which consistency must be guaranteed.
9 shows that the oldest vehicle speed data is stored in the storage buffer 7.
Therefore, the storage buffer for storing the latest vehicle speed data provided becomes the storage buffer 7 and updates the data storage order recording area 72 of the storage buffer 7 (B204 in FIG. 9).

Next, the data reference S / W1 in the (R + 1) th cycle is activated to request data reference (step S222 in FIG. 7). The buffer management S / W4 activated by the reference request for the data reference S / W1 confirms the information in the data storage order recording areas 62, 72, 82 and the data reference presence / absence recording areas 61, 71, 81 (step S10202 in FIG. 8). .
Looking at the data reference presence / absence recording area B204 in FIG. 9, it can be seen that the storage buffer 6 has already referred to the data reference S / W1. Looking at the data storage order recording area of B204 in FIG. 9, it can be seen that the latest vehicle speed data is stored in the storage buffer 7.
Therefore, the buffer management S / W 4 instructs the data reference S / W 1 to refer to the storage buffer 7, and records that the data reference S / W 1 refers to the data reference presence / absence recording area 71 of the storage buffer 7. (Step 10209 in FIG. 8). The data reference S / W1 performs arithmetic processing using the acquired data N + 1.
The status of each storage buffer after step S222 in FIG. 7 is B205 in FIG.

Next, the data reference S / W 3 is activated to request data reference (step S421 in FIG. 7). The buffer management S / W4 activated by the reference request of the data reference S / W3 confirms the information in the data storage order recording areas 62, 72, 82 and the data reference presence / absence recording areas 61, 71, 81 (step S10202 in FIG. 8). .
Looking at the data reference presence / absence recording area of B205 in FIG. 9, the storage buffer 6 and the storage buffer 7 have already been referred to by any data reference S / W, and the data reference S / W3 still refers to any storage buffer. You can see that it is not.
Further, in the data storage order recording area of B205 in FIG. 9, in the storage buffer 6 and the storage buffer 7 to which any data reference S / W has already been referenced, the storage buffer 6 stores older data. I understand that.
Therefore, the buffer management S / W 4 instructs the data reference S / W 3 to refer to the storage buffer 6 referred to by the previously activated data reference S / W 1 and data reference S / W 2 (step in FIG. 8). 10205), it records that the data reference S / W3 has referred to the data reference presence / absence recording area 61 of the storage buffer 6 (step 10206 in FIG. 8). Thereafter, the data reference S / W 3 performs a calculation process using the acquired data N.
The status of each storage buffer after step S321 in FIG. 7 is B206 in FIG.

At this time, when the data reference presence / absence recording area B206 in FIG. 9 is viewed, it can be seen that the vehicle speed data stored in the storage buffer 6 is referred to by all the data references S / W. Therefore, since it is not necessary to store the vehicle speed data in the storage buffer 6, all the data reference presence / absence recording areas 61 of the storage buffer 6 are unreferenced (step 10211 in FIG. 8).
The status of each storage buffer after step S421 in FIG. 7 is B207 in FIG.

Next, the data reference S / W2 in the R + 1 cycle is activated to request data reference (step S322 in FIG. 7). The buffer management S / W4 activated by the reference request for the data reference S / W2 confirms the information in the data storage order recording areas 62, 72, 82 and the data reference presence / absence recording areas 61, 71, 81 (step S10202 in FIG. 8). .
Looking at the data reference presence / absence recording area of B207 in FIG. 9, it can be seen that only the data reference S / W1 has been referred to in the storage buffer 7, and there is no data reference S / W referring to the storage buffer 6 and the storage buffer 8.
Therefore, the buffer management S / W 4 instructs the data reference S / W 2 to refer to the storage buffer 7 referred to by the previously activated data reference S / W 1 (step 10205 in FIG. 8). Is recorded in the data reference presence / absence recording area 71 (step 10206 in FIG. 8). Thereafter, the data reference S / W2 performs arithmetic processing using the acquired data N + 1.
The status of each storage buffer after step S322 in FIG. 7 is B208 in FIG.

Next, the data reference S / W3 in the R + 1 cycle is activated to request data reference (step S422 in FIG. 7). The buffer management S / W4 activated by the reference request of the data reference S / W3 confirms the information in the data storage order recording areas 62, 72, 82 and the data reference presence / absence recording areas 61, 71, 81 (step S10202 in FIG. 8). .
Looking at the data reference presence / absence recording area of B208 in FIG. 9, the storage buffer 7 has already been referred to the data reference S / W1 and the data reference S / W2, and the data reference S / W referring to the storage buffer 6 and the storage buffer 8 is I don't know. Therefore, the buffer management S / W4 instructs the data reference S / W3 to refer to the storage buffer 7 referred to by the previously activated data reference S / W1 and data reference S / W2 (step 10205 in FIG. 8). The data reference S / W 3 is recorded in the data reference presence / absence recording area 71 of the storage buffer 7 (step 10206 in FIG. 8). Thereafter, the data reference S / W 3 performs a calculation process using the acquired data N.
The status of each storage buffer after step S422 in FIG. 7 is B209 in FIG.

At this time, when the data reference presence / absence recording area B209 in FIG. 9 is viewed, it can be seen that the vehicle speed data stored in the storage buffer 7 is referred to by all the data references S / W.
Accordingly, since it is not necessary to store the vehicle speed data in the storage buffer 7, all the data reference presence / absence recording areas 71 of the storage buffer 7 are unreferenced (step 10211 in FIG. 8).
The status of each storage buffer after step S421 in FIG. 7 is B210 in FIG.

<Effect in Operation Example 2 of Embodiment 2>
According to the operation example 2 in the second embodiment, a plurality of storage buffers for storing data, an area for recording presence / absence of the data reference S / W for each storage buffer, and an area for recording the order of storing the data are provided. As a result, even if the execution order of the data reference S / Ws in different cycles is changed, it is possible to guarantee the data consistency required for the calculation with each data reference S / W.

<Operation example 3>
In the operation example 2, since the latest vehicle speed data is stored in the storage buffer, the consistency of data provided by the buffer management S / W 4 is not lost. However, storing the latest vehicle speed data in the storage buffer may break the data consistency. In the operation example 3, a method for guaranteeing data consistency in such a case will be described. The operation example 3 will be described with reference to FIGS. 8, 10, and 11.

In the operation example 2, only the activation order of the data reference S / W3 in the R cycle (step S421 in FIG. 7) and the data reference S / W1 in the R + 1 cycle (step S222 in FIG. 7) are switched.
In the operation example 3, new vehicle speed data (data N + 2) is acquired earlier than the data reference S / W3 in the R cycle (step S431 in FIG. 10) is activated (step S532 in FIG. 10), and the data in the R + 2 cycle. Consider the activation order of the data reference S / W when the reference S / W1 is activated (step S233 in FIG. 10).
At this time, the initial condition in the operation example 3 is the same as the initial condition in the operation example 2. Also, as shown in FIG. 11, the flow of processing until the data reference S / W1 is activated and calculation is performed using data N + 1 in the operation example 3 is the same as the process flow of the operation example 2.

In the operation example 3, the flow of processing from step S532 will be described.
After the data reference S / W1 is activated and calculated using the data N + 1, the buffer management S / W4 acquires the latest vehicle speed data (data N + 2) (step S532 in FIG. 10). In the second embodiment, when the latest data is acquired, it is assumed that it is stored in the oldest storage buffer among the storage buffers not referring to any data reference S / W at that time.
Looking at the data reference presence / absence recording area of B305 in FIG. 11, the storage buffer 6 and the storage buffer 7 store data whose consistency must be guaranteed, and therefore cannot be updated with the latest data. Regarding the storage buffer 8, since no data reference S / W is referred to, it is not data for which consistency must be guaranteed.
11 shows that the oldest vehicle speed data is stored in the storage buffer 8. In FIG.
Therefore, the buffer for storing the latest vehicle speed data provided is the storage buffer 8, and the data storage order recording area 82 of the storage buffer 8 is updated (B306 in FIG. 11).

Next, the data reference S / W1 in the R + 2 cycle is activated to request data reference (step S233 in FIG. 10). The buffer management S / W4 activated by the reference request for the data reference S / W1 confirms the information in the data storage order recording areas 62, 72, 82 and the data reference presence / absence recording areas 61, 71, 81 (step S10202 in FIG. 8). .
Looking at the data reference presence / absence recording area of B306 in FIG. 11, it can be seen that the storage buffer 6 and the storage buffer 7 have already referred to the data reference S / W1. Looking at the data storage order recording area of B306 in FIG. 11, it can be seen that the latest vehicle speed data is stored in the storage buffer 8.
Therefore, the buffer management S / W 4 instructs the data reference S / W 1 to refer to the storage buffer 8, but if the data reference S / W 1 refers to the storage buffer 8, all the storage buffers In FIG. 11, the data reference S / W1 is already referred to (B307 in FIG. 11). That is, the state of B307 in FIG. 11 means that data for which consistency must be guaranteed is stored in all the storage buffers.

Here, it is assumed that new data (data N + 3) is acquired (step S533 in FIG. 10). If there is no storage buffer that does not refer to any data reference S / W, the latest data is stored in the oldest storage buffer, so the buffer management S / W 4 stores data N + 3 in the storage buffer 6. (B308 in FIG. 11).
Then, since the data reference S / W3 that does not refer to the data N originally stored in the storage buffer 6 cannot refer to the data N, the buffer management S / W4 stores the data with guaranteed consistency. It cannot be provided for the data reference S / W3.

Therefore, whether or not the data reference S / W1 that has requested data reference in the state of B306 in FIG. 11 has already referred to all the storage buffers in which data other than the latest data is stored. It is determined whether or not (step S10208 in FIG. 8). As a result of the determination, if there is an unreferenced storage buffer in which data other than the latest data is stored, an instruction is given to refer to the storage buffer in which the latest data is stored (step S1 in FIG. 8).
0209), otherwise, nothing is indicated (instruction not to refer to the storage buffer).
As a result, the state of B307 in FIG.

<Effect in Operation Example 3 of Embodiment 2>
According to the operation example 3 in the second embodiment, by recording the presence / absence of each data reference S / W for each storage buffer, it is possible to detect a situation in which the consistency of data is lost.
When a situation where the integrity of data is lost is detected, the data reference S / W is instructed not to refer to the storage buffer, thereby guaranteeing the consistency of the data stored in the storage buffer. can do.

<Operation example 4>
According to the operation example 3, it is determined whether or not the data consistency is lost when the data reference S / W reference request is made. However, if it is possible to determine whether or not the data consistency is lost before the data reference is requested, it is possible to reduce unnecessary reference requests for the data reference S / W.

Therefore, the activation time of each data reference S / W is measured by the time measuring means, and the activation interval of the data reference S / W is calculated by the buffer management S / W4.
The buffer management S / W 4 determines the data reference S / W having an extremely short activation interval by comparing the calculated activation intervals of the data reference S / Ws.
When there is a data reference S / W whose activation interval is extremely short, the activation timing of the data reference S / W is adjusted so that the activation interval is about the same as the other data reference S / W.

Consider a case where the activation interval between the data reference S / W1 and the data reference S / W2 as shown in FIG. 12 is shorter than the data reference S / W3.
Looking at time T1 in FIG. 12, the data reference S / W3 is the timing when the fifth activation starts, but the data reference S / W2 is the sixth activation, and the data reference S / W1 is the eighth activation. It is becoming a situation where the consistency of

Therefore, as shown in FIG. 13, the buffer management S / W4 incorporates the adjustment time into the execution intervals of the data reference S / W1 and the data reference S / W2 with short activation intervals (adjustment times AT1, AT2 in FIG. 13). ), Matching with the activation timing of the data reference S / W3 having the longest activation interval.
In this case, the data reference S / W requesting the data reference is requested again after the adjustment time, or the data reference S / W is instructed by the next data reference request timing.
By this processing, it is possible to reduce the frequency of switching the start order of the data reference S / W and to reduce unnecessary reference requests for the data reference S / W.

<Effect in Operation Example 4 of Embodiment 2>
According to the operation example 4 in the second embodiment, a plurality of storage buffers for storing data, an area for recording presence / absence of reference of the data reference S / W for each storage buffer, and an area for recording the order of storing data, By providing means for measuring the activation time of the data reference S / W, the activation timing of the data reference S / W can be adjusted to bring the data reference S / W closer to the ideal activation order (see FIG. 2). it can.
Then, by bringing the data reference S / W closer to the ideal startup order, it is possible to avoid a situation in which data consistency is lost.

In the present invention, the embodiments can be freely combined within the scope of the invention,
Each embodiment can be modified or omitted as appropriate.

1-3 Data reference S / W
4 Buffer management S / W
41 Operation data storage buffer 411 Data reference presence / absence recording area 6-8 Storage buffer 61 Data reference presence / absence recording area 62 for storage buffer 6 Data storage order recording area 71 for storage buffer 6 Data reference presence / absence recording area 72 for storage buffer 7 Storage buffer 7 data storage order recording area 81 storage buffer 8 data reference presence / absence recording area 82 storage buffer 8 data storage order recording area

In the data integrity guarantee system according to the present invention, a plurality of data reference means for performing calculations using data respectively, data used for the calculations by the data reference means are stored, and whether data is referenced by the data reference means is recorded. A storage buffer having a data reference presence / absence recording area, and buffer management means for managing storage of data in the storage buffer and reference by the data reference means for the stored data. If all data reference means are unreferenced in the data reference presence / absence recording area, new data is stored in the storage buffer , one of the data reference means is already referenced, and one of the data reference means is not yet without storing the new data to the storage buffer in the case of the reference, and discarded, the data When the reference means requests to reference the data stored in the storage buffer, if the data reference means is unreferenced in the data reference presence / absence recording area, the data reference means is instructed to refer to the data in the storage buffer. When the reference by the data reference means is recorded in the data reference presence / absence recording area and the data reference presence / absence recording area of the storage buffer is already referenced by all the data reference means, all the data reference presence / absence recording areas of the storage buffer are recorded. This data reference means makes it unreferenced.

According to this invention, the data reference presence / absence recording area for storing a plurality of data reference means for performing calculations using data, storing data used for the calculation by the data reference means, and recording the presence / absence of data reference by the data reference means And a buffer management means for managing storage of data in the storage buffer and reference by the data reference means for the stored data, the buffer management means including a data reference presence / absence recording area of the storage buffer If all data reference means are unreferenced, new data is stored in the storage buffer , and if any data reference means is already referenced and any data reference means is unreferenced , new data is stored. such data without storing into a storage buffer, discard, data reference means is stored in the storage buffer If the data reference means is not referenced in the data reference presence / absence recording area, the data reference means is instructed to refer to the data in the storage buffer and the data reference presence / absence recording area When the reference by the data reference means is recorded and the data reference presence / absence recording area of the storage buffer is already referenced by all the data reference means, the data reference presence / absence recording area of the storage buffer is unreferenced by all the data reference means. Therefore, new data can be stored in the storage buffer at a timing at which the data consistency is not lost, and the consistency of the data used by the plurality of data reference means can be ensured.

Claims (4)

A plurality of data reference means for performing calculations using data respectively;
A storage buffer for storing data used for the calculation by the data reference means and having a data reference presence / absence recording area for recording presence / absence of reference of the data by the data reference means,
And buffer management means for managing storage of data in the storage buffer and reference by the data reference means for the stored data,
The buffer management means includes
When all the data reference means are unreferenced in the data reference presence / absence recording area of the storage buffer, new data is stored in the storage buffer,
When the data reference means requests to reference the data stored in the storage buffer, if the data reference means is unreferenced in the data reference presence / absence recording area, the data reference means stores the data in the storage buffer. Instructing the reference and recording the reference by the data reference means in the data reference presence / absence recording area,
When the data reference presence / absence recording area of the storage buffer is already referred to by all the data reference means, all the data reference means unreference the data reference presence / absence recording area of the storage buffer. Data integrity assurance system. A plurality of data reference means for performing calculations using data respectively;
A plurality of data reference presence / absence recording areas for recording data used by the data reference means for recording the data used by the data reference means and a storage order recording area for recording the data storage order. Storage buffer,
And buffer management means for managing the storage of the data in the plurality of storage buffers and the reference by the data reference means for the stored data,
The buffer management means includes
When storing new data in the storage buffer, the storage buffer is selected based on the buffer storage order recording area and the data reference presence / absence recording area according to the timing at which the new data is acquired. After storing the data, update the storage order recorded in the storage order recording area of the storage buffer storing the new data,
When the data reference means requests reference to the data stored in the storage buffer, the data reference means is instructed to refer to the storage buffer based on the storage order recording area and the data reference presence / absence recording area. And records the reference by the data reference means in the data reference presence / absence recording area of the storage buffer,
When the data reference presence / absence recording area of any storage buffer is already referred to by all the data reference means, the data reference presence / absence recording area of the storage buffer is unreferenced by all the data reference means. A data integrity guarantee system.   If the data reference unit has already referred to all the storage buffers in which data other than the latest data is stored at the timing when the data reference unit requests reference to the data, the buffer management unit may refer to the data reference unit. 3. The data integrity guarantee system according to claim 2, wherein an instruction is made not to refer to any of the storage buffers. A time measuring means for measuring an activation time for referring to the data of each of the data referring means,
The buffer management means determines the activation time of the data reference means when the activation interval, which is the difference between the activation times of the data reference means measured by the time measurement means, is shorter than the activation intervals of the other data reference means. 3. The data integrity guarantee system according to claim 2, wherein adjustment is performed.

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