JP2022175365A - Electronic control device and failure information erasing method - Google Patents

Abstract

To suppress the occurrence of processing overflow due to the erasure of failure information in an electronic control device in which the failure information is stored in a non-volatile memory.SOLUTION: An electronic control device, in which failure information of a function to be diagnosed is stored in a non-volatile memory, sets a flag indicating whether or not there is a request for erasure upon receiving a request to erase the failure information from a diagnostic tool. Further, when the timing for diagnosing the function to be diagnosed according to a predetermined schedule comes, the electronic control device exclusively executes processing of erasing the failure information and clearing the flag (S31, S32) according to the set state of the flag (S30), and processing of diagnosing the function to be diagnosed (S33).SELECTED DRAWING: Figure 6

Description

The present invention relates to an electronic control device in which failure information is stored in a non-volatile memory, and a method of erasing the failure information.

An electronic control unit mounted on a vehicle detects a failure by a diagnostic function and writes and saves it in a non-volatile memory. The failure information stored in the non-volatile memory is referenced and deleted by a diagnostic tool detachably connected to the electronic control unit, as described in Japanese Patent Application Laid-Open No. 2010-139458 (Patent Document 1).

JP 2010-139458 A

An electronic control unit mounted on a vehicle needs to execute diagnostic processing and normal processing of a controlled object in each control cycle at predetermined time intervals. When a diagnostic tool is connected to the electronic control unit and fault information is erased, the electronic control unit must perform erasure processing in addition to diagnostic processing and normal processing, and all processing is completed within the control cycle. If not, "processing overflow" will occur. Then, when a process overflow occurs, the process related to the process overflow cannot be executed, and, for example, in the case of normal processing, the control of the controlled object is affected.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an electronic control unit and a method for erasing failure information that suppresses the occurrence of processing overflow due to erasure of failure information.

The electronic control unit, in which the failure information of the function to be diagnosed is stored in the non-volatile memory, sets a flag indicating whether or not there is a request for erasure of the failure information when an external device requests erasure of the failure information. Further, when the timing for diagnosing the function to be diagnosed according to a predetermined schedule comes, the electronic control unit erases the failure information and clears the flag according to the set state of the flag, and executes the function to be diagnosed. A process to diagnose and a are executed exclusively.

According to the present invention, it is possible to suppress the occurrence of processing overflow due to deletion of failure information in an electronic control unit.

1 is a schematic diagram showing an example of an electronic control system mounted on a vehicle; FIG. It is a schematic diagram showing an example of an internal structure of an electronic control unit. 4 is a block diagram showing an example of modules implemented by an application program; FIG. 6 is a flow chart showing an example of request analysis processing executed by an event manager; 6 is a flow chart showing an example of an erasure flag setting process executed by an erasure request receiving unit; 4 is a flowchart showing an example of diagnostic processing executed by a diagnostic unit; 4 is a flow chart showing an example of failure information erasing processing executed by a failure information erasing unit; It is explanatory drawing of the operation|movement and effect in a prior art. FIG. 4 is an explanatory diagram of actions and effects in the proposed technology;

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the attached drawings.
The vehicle 100 is equipped with a plurality of electronic control units 200 that electronically control, for example, an engine, an automatic transmission, an adaptive cruise control system, and the like. A plurality of electronic control units 200 are connected so as to be able to transmit and receive arbitrary data via an in-vehicle network 300 such as a CAN (Controller Area Network), for example. Here, the vehicle 100 can be a passenger car, truck, bus, construction machine, or the like. In the example shown in FIG. 1, four electronic control units 200 are mounted on vehicle 100, but the number of electronic control units 200 is arbitrary.

As shown in FIG. 2, the electronic control unit 200 includes a processor 210 such as a CPU (Central Processing Unit), a nonvolatile memory 220, a volatile memory 230, an input/output circuit 240, a communication circuit 250, and these. and an internal bus 260 that are interconnectably connected.

The processor 210 is hardware that executes an instruction set (data transfer, operation, processing, control, management, etc.) described in an application program, and includes an arithmetic unit, registers that store instructions and data, peripheral circuits, and the like. It is configured. The non-volatile memory 220 is made up of a flash ROM (Read Only Memory), an EEPROM (Electrically Erasable Programmable Read Only Memory), etc. that can retain data even when the power supply is interrupted. Holds failure information. The volatile memory 230 includes a dynamic random access memory (RAM) that loses data when the power supply is cut off, and provides a storage area for temporarily storing parameters during the operation process of the processor 210 .

The input/output circuit 240 includes an A/D converter, a D/A converter, a D/D converter, etc., and provides an input/output function of analog signals and digital signals to sensors, switches, actuators, and the like. The communication circuit 250 is composed of, for example, a CAN transceiver or the like, and provides a function of connecting to the in-vehicle network 300 and a function of detachably connecting to the diagnostic tool 500 via the cable 400 . The internal bus 260 is a path for exchanging data between devices, and includes an address bus for transferring addresses, a data bus for transferring data, and actual input/output through the address bus and data bus. It includes a control bus that communicates timing and control information. Note that the diagnostic tool 500 is an example of an external device.

Here, after being connected to the electronic control unit 200 via the cable 400, the diagnostic tool 500 transmits a request including a failure information deletion request to the electronic control unit 200 in response to the operator's operation. . At this time, in view of the fact that failure information relating to a plurality of diagnostic target functions is stored in the non-volatile memory 220 of the electronic control unit 200, the diagnostic tool 500 combines information that can specify which failure information is to be erased. to send. In short, diagnostic tool 500 sends an erase request for each function to be diagnosed. On the other hand, the electronic control unit 200, which has received the request from the diagnostic tool 500, specifies the failure information to be erased from the information transmitted together with the failure information, and erases this failure information.

Then, the processor 210 of the electronic control unit 200 responds to normal processing for controlling the controlled object, diagnostic processing for detecting and storing failures, and deletion requests from the diagnostic tool 500 according to the application program stored in the nonvolatile memory 220. In response, erase processing is executed to erase the failure information. Here, the normal processing and the diagnostic processing are well known to those skilled in the art and are not essential parts of the present embodiment, so description thereof will be omitted.

As shown in FIG. 3, the processor 210 of the electronic control unit 200 is a module that performs normal processing, diagnostic processing, and erasing processing. As shown in FIG. The erasing unit 210D is implemented.

When event manager 210A receives a request from diagnostic tool 500 connected to electronic control unit 200, event manager 210A analyzes the request to determine whether or not it is an erasure request. A processing request is transmitted to the section 210B. When the erasure request receiving unit 210B receives the erasure request from the event manager 210A, the erasure request receiving unit 210B sets the erasure flag FLG secured in the volatile memory 230, for example, to TRUE. Here, the erasure flag FLG is an example of a flag indicating whether or not there is an erasure request.

Diagnosis unit 210C refers to erasure flag FLG in volatile memory 230 when the timing for diagnosing a function to be diagnosed according to a predetermined schedule has come, and if erasure flag FLG is set, failure information is erased. An erasure request is sent to the unit 210D to clear the erasure flag FLG, for example, to set the erasure flag FLG to FALSE. Further, if the erasure flag FLG of the volatile memory 230 is not set, that is, if the erasure flag FLG is cleared, the diagnosis unit 210C executes well-known diagnosis processing. Further, when the diagnosis unit 210</b>C detects a failure in the function to be diagnosed as a result of executing the diagnosis process, the diagnosis unit 210</b>C writes and stores failure information INF that can identify the failure in the nonvolatile memory 220 . The fault information erasing unit 210D erases the fault information INF to be erased from the non-volatile memory 220 when the erasure request is received from the diagnosis unit 210C.

FIG. 4 shows an example of request analysis processing that is executed when the event manager 210A receives a request from the diagnostic tool 500 as a trigger.

In step 10 (abbreviated as “S10” in FIG. 4, hereinafter the same), the event manager 210A analyzes the content of the request received from the diagnostic tool 500. FIG. Specifically, when diagnostic tool 500 is connected to electronic control unit 200 via the CAN protocol, event manager 210A refers to the header of the CAN packet received from diagnostic tool 500 and uses a predetermined identifier to determine the request content. identify.

At step 11, the event manager 210A determines whether the request is an erasure request according to the analysis result at step 10. FIG. If the event manager 210A determines that the request is an erasure request (Yes), the process proceeds to step 12 . On the other hand, if the event manager 210A determines that the request is not a processing request (No), the process proceeds to step 13 .

At step 12, the event manager 210A transmits an erasure request to the erasure request receiving section 210B. After that, the event manager 210A terminates the request analysis process.

At step 13, event manager 210A sends a request to a module (not shown) that handles requests from diagnostic tool 500. FIG. After that, the event manager 210A terminates the request analysis process. A module that receives a request from the diagnostic tool 500 executes processing according to the request.

According to the request analysis process, when the diagnostic tool 500 issues a request to the electronic control unit 200, the request is analyzed to determine whether or not it is an erasure request. Then, if the request is an erasure request, this is transmitted to erasure request receiving section 210B. On the other hand, if the request is not an erase request, the request is sent to the module that handles the request. In short, the event manager 210A analyzes requests from the diagnostic tool 500 and distributes the requests to the modules that process them according to the results of the analysis.

FIG. 5 shows an example of erasure flag setting processing that is executed by the erasure request reception unit 210B upon receipt of an erasure request from the event manager 210A.

At step 20 , the erasure request reception unit 210</b>B sets the erasure flag FLG of the volatile memory 230 . After that, the erasure request receiving unit 210B terminates the erasure flag setting process.

According to the erasing flag setting process, when the event manager 210A issues an erasing request to the erasing request receiving unit 210B, the erasing flag of the volatile memory 230 is set without erasing the failure information INF stored in the nonvolatile memory 220. FLG is set. Therefore, after the erasure flag FLG of the volatile memory 230 is set, by referring to it, it is possible to know at any time that there is an erasure request from the diagnostic tool 500 .

FIG. 6 shows an example of diagnostic processing executed by the diagnostic section 210C when the timing for diagnosing a diagnostic target function according to a predetermined schedule comes. The diagnosis unit 210C diagnoses at least one function to be diagnosed according to a predetermined schedule.

At step 30, the diagnostic unit 210C refers to the erasure flag FLG of the volatile memory 230 and determines whether or not it is set, thereby determining whether or not there is an erasure request for the function to be diagnosed. Then, if the diagnosis unit 210C determines that there is an erasure request (Yes), the process proceeds to step 31 . On the other hand, if the diagnosis unit 210C determines that there is no erasure request (No), the process proceeds to step 33 .

At step 31, the diagnosis section 210C transmits an erasure request to the failure information erasure section 210D.

At step 32 , diagnostic unit 210</b>C clears erasure flag FLG of volatile memory 230 . After that, the diagnosis unit 210C terminates the diagnosis process.

At step 33, the diagnosis unit 210C diagnoses whether the function to be diagnosed is normal or abnormal using a well-known technique because there is no erasure request. If the diagnostic unit 210C diagnoses that the function to be diagnosed is abnormal, the diagnostic unit 210C writes and stores in the nonvolatile memory 220 failure information INF that can identify this. After that, the diagnosis unit 210C terminates the diagnosis process.

According to this diagnosis process, when the timing for diagnosing the function to be diagnosed according to the predetermined schedule comes, the diagnosis unit 210C, if there is a deletion request, transmits the deletion request to the fault information deletion unit 210D, The erase flag FLG of the volatile memory 230 is cleared. On the other hand, the diagnosis unit 210C diagnoses the function to be diagnosed if there is no erasure request.

FIG. 7 shows an example of failure information erasing processing executed by the failure information erasing section 210D when the diagnosis section 210C issues an erasing request to the failure information erasing section 210D.

At step 40, the failure information erasing section 210D erases from the non-volatile memory 220 the failure information INF of the function associated with the erasure request. After that, the failure information erasing section 210D terminates the failure information erasing process.

According to this failure information erasing process, when an erasure request is issued from the diagnosis part 210C to the failure information erasure part 210D, the failure information INF of the function associated with the erasure request is erased from the nonvolatile memory 220. FIG.

Therefore, the event manager 210A, the erasure request reception unit 210B, the diagnosis unit 210C, and the failure information erasure unit 210D jointly set the erasure flag FLG in response to the erasure request from the diagnostic tool 500, and diagnose the function to be diagnosed. If the erasing flag FLG is set at the timing, the fault information INF is erased and the erasing flag FLG is cleared without executing diagnostic processing. On the other hand, if the erase flag FLG is not set at the timing of diagnosing the function to be diagnosed, the diagnosis is executed without erasing the failure information INF. In other words, instead of immediately deleting the failure information INF in response to an erasure request from the diagnostic tool 500, when the subsequent diagnostic timing comes, according to the set state of the erasure flag FLG, A process of erasing the failure information INF and clearing the erasure flag FLG and a process of diagnosing the function to be diagnosed are exclusively executed.

Here, the operation and effects of the electronic control unit 200 according to this embodiment will be described. In the following description, diagnostic processes A, B and C, erasing processes A, B and C, and normal processes for controlling controlled objects are performed for functions A, B and C in a control cycle that is a predetermined time interval. It is assumed that each is executed. In addition, normal processing includes at least one processing, but these are collectively represented.

In the prior art, as shown in FIG. 8, in the pattern A in which there is no request to erase the failure information INF related to the functions A to C, even if the diagnostic processes A to C and the normal process are sequentially executed, all of the data are processed within the control cycle. Processing ends. Also, in pattern B where there is a request to erase failure information INF related to function A, even if erasing process A, diagnostic processes A to C, and normal process are executed in sequence, all the processes are still completed within the control cycle. However, in pattern C, which requests deletion of fault information INF related to functions A to C, if deletion processing A to C, diagnostic processing A to C, and normal processing are sequentially executed, all processing will not be completed within the control cycle. For example, processing overflow occurs in normal processing.

In the proposed technique, as shown in FIG. 9, in the pattern A where there is no request to erase the failure information INF related to the functions A to C, even if the diagnostic processes A to C and the normal process are sequentially executed, the , all processing is completed within the control cycle. In pattern B, in which there is a request to erase failure information INF related to function A, diagnostic process A is not executed for function A, only erasing process B is executed, and diagnostic processes B and C related to functions B and C are executed. For this reason, in pattern B, erasing process A, diagnostic processes B and C, and normal process are sequentially executed, and all the processes are completed within the control cycle. You can understand something. In addition, in pattern C where there is a request to erase failure information INF related to functions A to C, diagnostic processes A to C are not executed for functions A to C, and only erasing processes A to C are executed. For this reason, in pattern C, erasing processes A to C and normal processing are executed, and all the processes are completed within the control cycle. will be able to understand

In the electronic control unit 200 according to the present embodiment, when there is an erasure request from the diagnostic tool 500, the diagnostic target function associated with the erasure request is not diagnosed at the subsequent diagnosis timing. Since it is executed in the next control cycle, there is almost no effect on accumulation of failure information.

It should be noted that those skilled in the art can omit some of the technical ideas of the above-described embodiments, appropriately combine some of them, or replace some of them with well-known techniques to create new It will be readily understood that various embodiments can be produced.

For example, the event manager 210A may set the erasure flag FLG of the volatile memory 230 by itself instead of transmitting the erasure request to the erasure request reception unit 210B. In this case, the processor 210 of the electronic control unit 200 does not need to implement the erasure request receiving section 210B.

Diagnosis section 210C may erase failure information INF from non-volatile memory 220 by itself instead of sending an erasure request to failure information erasure section 210D. In this case, the processor 210 of the electronic control unit 200 does not need to implement the failure information erasing section 210D.

200 electronic controller 220 non-volatile memory 500 diagnostic tool (external device)
FLG Erase flag (flag)
INF Failure information

Claims (5)

An electronic control unit in which failure information of a function to be diagnosed is stored in a non-volatile memory,
when an external device requests erasure of the fault information, setting a flag indicating whether or not there is an erasure request;
When the timing for diagnosing the function to be diagnosed according to a predetermined schedule is reached, a process of erasing the fault information and clearing the flag according to the set state of the flag, and diagnosing the function to be diagnosed. to exclusively execute the process and
electronic controller. When it is time to diagnose the function to be diagnosed, if the flag is set, the fault information is erased and the flag is cleared; if the flag is not set, the diagnosis target perform a process that diagnoses the functionality of the
The electronic control unit according to claim 1. The erasure request is made for each function to be diagnosed.
The electronic control device according to claim 1 or 2. The external device is a detachably connected diagnostic tool,
The electronic control device according to any one of claims 1 to 3. An electronic control unit in which failure information of a function to be diagnosed is stored in a non-volatile memory,
when an external device requests erasure of the fault information, setting a flag indicating whether or not there is an erasure request;
When the timing for diagnosing the function to be diagnosed according to a predetermined schedule is reached, a process of erasing the fault information and clearing the flag according to the set state of the flag, and diagnosing the function to be diagnosed. to exclusively execute the process and
How to clear fault information.

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