JP2009026183A - Electronic control apparatus for automobile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to rewrite a rewritten control constant to a suitable control constant again without executing boot rewriting even when a control constant stored in a nonvolatile memory capable of electrically erasing and writing data is rewritten to a version which does not suit to a control program. <P>SOLUTION: An electronic control apparatus for an automobile compares a version of a control program stored in the nonvolatile memory with that of a control constant when starting, and executes the control program when both the versions are suited to each other, or executes a memory rewriting program when both the versions are not suited to each other. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an automotive electronic device comprising a nonvolatile memory in which data can be electrically erased and written, and a memory rewrite program, a control program, and control constants used for the control program are stored in respective areas. The present invention relates to a control device.

Patent Document 1 discloses an electronic control device for a vehicle including a flash memory that is a nonvolatile memory capable of electrically erasing and writing data.
The flash memory is designed to be erased / written in block units of memory cells, and is divided into a memory writing program area, a control program area, and a control constant area.
JP 2000-257502 A

By the way, as described above, the area of the flash memory is divided into a memory writing program area, a control program area, and a control constant area, and each area can be erased and written separately. May be rewritten to a different control constant.
If the versions of the control program and the control constant are different, the control program cannot be executed normally due to a difference between the address where the control program reads and the address where the control constant is actually stored. Therefore, it becomes impossible to execute a memory writing program by judging a rewrite request of the flash memory.

Therefore, if rewriting that does not match the version is performed, the electronic control device for a car that does not have a boot pin cannot be rewritten to the correct version, and the entire electronic control device must be replaced. was there.
The boot pin is for enabling a data program to be transferred from the connected host processor to all memory spaces by a combination of signals input to the boot pin. Even if rewriting that does not match the version is performed, rewriting to the correct version is possible.

However, for example, when the electronic control device for automobiles is waterproof, the boot pin may be omitted. In this case, if rewriting that does not match the version is performed, rewriting becomes impossible. Is.
The present invention has been made in view of the above problems, and even when the program is rewritten to a combination of a non-conforming control program and a control constant, it is not necessary to rewrite the boot, and the control program or control constant can be restored. An object of the present invention is to provide an automotive electronic control device that can be rewritten.

Therefore, according to the first aspect of the present invention, the electronic control device for an automobile determines whether the control program stored in the nonvolatile memory matches the control constant at the time of start-up, and executes the control program if it matches. If not, the memory rewrite program stored in the non-volatile memory is executed.
According to the above invention, for example, when the automotive electronic control device is started after rewriting the control constant, it is determined whether the rewritten control constant is compatible with the control program. If the program is executed but does not fit, the control constant can be rewritten by executing the memory rewriting program.

Therefore, even if it is accidentally rewritten to a combination of control program and control constant with different versions, it is possible to rewrite to the correct version combination without rewriting the boot, preventing control abnormality It is also possible to eliminate the need to replace the entire electronic control unit.
In the invention described in claim 2, the matching between the control program and the control constant is determined by collating the identification information included in each of the control program and the control constant.

According to the above invention, matching such as version matching is determined by comparing the identification information given to the control program with the identification information given to the control constant.
Therefore, it is possible to accurately and easily determine conformity such as version matching.
In the invention of claim 3, identification information in the control program and control constant is version information.

According to the above invention, the control constant and the version information of the control program are provided in the control program and the control constant stored in the nonvolatile memory, and conformity / non-conformity is determined by comparing the versions.
Therefore, when a combination of a control constant and a control program that are incompatible due to different versions is stored, it is possible to rewrite the correct version and prevent a control abnormality.

According to a fourth aspect of the invention, when the control program and the control constant do not match, the memory rewriting program is executed, and when the writing of the control program and / or the control constant is not normally completed. Also, the memory rewriting program is executed.
According to the above invention, the memory rewriting program is executed instead of the control program at the start-up even when the control program and / or the control constant is not normally written and there is a possibility that the control is abnormal.

Therefore, when it is necessary to rewrite without writing normally, even if the control program does not operate normally due to a write error, the memory rewriting program can be executed to perform rewriting. .
According to a fifth aspect of the present invention, the memory rewriting program communicates with an external rewriting tool connected to the automobile electronic control device to rewrite the control program and / or control constant.

According to the above invention, when it is determined that the control program and the control constant do not match and the memory rewriting program is executed, communication is performed with an external rewriting tool connected to the automotive electronic control device. The rewrite data is read from the tool, and the control program and / or control constant stored in the nonvolatile memory is rewritten.
Therefore, even when the control program does not normally operate because the control program and the control constant do not match, it is possible to communicate with the external tool and rewrite using the external tool.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a configuration of an automotive electronic control unit (ECU) 1 according to an embodiment.
The electronic control device 1 for an automobile controls a control target (engine, automatic transmission, etc.) mounted on the automobile, and a flash memory 2 which is a nonvolatile memory capable of electrically erasing and writing data. The RAM 3 and the microcomputer 4 are included.

The microcomputer 4 includes a CPU, a built-in RAM, a timer, an A / D converter, an SCI, and the like, and executes various programs stored in the RAM 3 and the flash memory 2.
In the flash memory 2, the storage area is divided into three blocks A, B, and C, and at the time of rewriting, the stored data is erased and written in units of the blocks.

A flash rewrite program (memory rewrite program) is stored in block A of the flash memory 2, a control constant (compatible constant) is stored in block B, and a control program (application program) is stored in block C.
The control constant and the control program are stored in the blocks B and C together with the identification information ID indicating the version.

  The flash rewrite program of the block A is a program for controlling the control constants stored in the blocks B and C and the erasing / writing of the control program, and the control program of the block B is stored in the block C. An operation signal is output to a control device (fuel injection valve, solenoid, etc.) of a control target (engine, automatic transmission, etc.) mounted on the automobile by arithmetic processing using control constants and various input signals.

Examples of the various input signals include operation signals from various operation devices 7 and detection signals from a detection device 8 that detects a driving state of the vehicle.
When the automobile electronic control device 1 is a device for controlling an engine, the operation device 7 includes an engine ignition switch, and the detection device 8 includes an engine rotation sensor, a load sensor, and the like. .

After the control constant and the control program are stored in the flash memory 2, when the control constant and / or the control program is updated (upgraded), the flash rewrite program executes the control constant and / or the control program. By rewriting, the version of the automotive electronic control device 1 can be updated.
When performing the rewriting, as shown in FIG. 1, a flash writing tool 5, which is an external tool for rewriting, is connected to the automobile electronic control device 1 via a communication line 6.

  When the flash rewriting program is executed on the vehicle electronic control device 1 side in a state where the flash writing tool 5 and the vehicle electronic control device 1 are connected, the vehicle electronic control device 1 and the flash writing are executed. Communication with the tool 5 is performed, and a new version of the control constant and / or control program stored in the flash memory 5a provided in the flash writing tool 5 is read into the automotive electronic control device 1. The control constants and / or control programs stored in the blocks B and C are rewritten with new versions.

Even when the control constant / control program is rewritten using the flash writing tool 5, the identification information ID indicating the newly written control constant / control program version is stored in the blocks B and C. is there.
In other words, the identification information ID indicating the version is previously assigned to the control constant / control program, and the control constant / control program to which the identification information ID is assigned is stored in the flash memory 2. Yes.

Here, how the flash writing tool 5 rewrites control constants and control programs will be described with reference to the flowchart of FIG.
When the automotive electronic control device 1 determines a write request from the flash writing tool 5 with the flash writing tool 5 connected to the automotive electronic control device 1, the flash rewriting program is executed, and the automotive electronic control device 1. Shifts to the flash rewrite mode (step S101).

In the flash rewrite mode, rewrite processing is performed by communication between the flash writing tool 5 and the automotive electronic control device 1, and first, an area to be rewritten is determined (step S102).
When rewriting only the control constant, after erasing the block B, a new version of the control constant transmitted from the flash writing tool 5 is written into the block B together with the identification information ID indicating the version (step S103). ).

  On the other hand, when rewriting the control program together with the control constant, after erasing the block B, a new version of the control constant transmitted from the flash writing tool 5 is written into the block B together with the identification information ID indicating the version, Further, after erasing the block C, a new version of the control program transmitted from the flash writing tool 5 is written into the block C together with the identification information ID indicating the version (step S104).

It is obvious that the order of erasing / writing in each block is not limited to the order of block B → block C, and erasing / writing can be performed in the order of block C → block B.
The arrangement of the blocks in the flash memory is not limited to the above order.
When rewriting only the control program, after erasing the block C, a new version of the control program transmitted from the flash writing tool 5 is written in the block C together with the identification information ID indicating the version (step S105). ).

  As described above, when both the control constant and the control program are upgraded at the same time, and the control program is rewritten at the same time as the control constant, the version of the control constant and the version of the control program match even after rewriting. However, for example, when only the control constant or only the control program is rewritten, the version of the control program that is not rewritten matches the version of the control constant that is rewritten unless the flash writing tool 5 has a version information confirmation function. There is a possibility of disappearing.

  Here, because the version of the control program is different from the version of the control constant, for example, if the address where the control constant is actually written deviates from the address where the control program goes to read, the control routine enters an infinite loop. , Division by zero, or the initial value of the communication setting or the register setting value may change, resulting in abnormal control operation or reset / communication failure. It becomes impossible to do.

Therefore, in this embodiment, even if the versions of the control program and the control constant stored in the flash memory 2 become inconsistent due to erroneous rewriting, the flash memory 2 can be rewritten and rewritten. A process for enabling the above will be described with reference to the flowchart of FIG.
First, when the automotive electronic control device 1 is activated (power-on reset) (step S201), the control program and / or control constants are normally written to the flash memory 2, and the control program It is determined whether the identification information ID indicating the version matches the identification information ID indicating the version of the control constant, and the control program and the control constant match (step S202).

When rewriting is normally completed, identification information indicating the normal completion of rewriting is stored for each of the blocks B and C, and whether or not writing has been normally performed by determining the normal completion identification information. Judgment is made.
Whether the identification information ID indicating the version of the control program matches the identification information ID indicating the version of the control constant is determined by reading the identification information ID indicating the version stored for each of the blocks B and C. Judged by matching.

When the writing is completed normally, the identification information ID indicating the version is stored, and when no identification information ID indicating the version is stored, it is determined that the writing has not been performed normally. Can be made.
If the writing is completed normally and the version of the control program matches the version of the control constant, the control program can be executed normally, so that the control program (application program) is normally executed. Is executed (step S203).

On the other hand, if writing has not been completed normally, even if the versions match, normal control operation cannot be performed, so flash rewriting is required to complete writing normally by re-writing operation. A program (memory rewriting program) is executed (step S204).
In addition, when the version of the control program and the version of the control constant do not match, normal control operation cannot be performed even if rewriting of the control program and / or control constant is completed normally. Therefore, also in this case, the flash rewrite program (memory rewrite program) is executed (step S204).

When the flash rewrite program (memory rewrite program) is executed, communication with the flash writing tool 5 is performed in the flash rewrite control, and the correct version of the control program is performed by the write processing shown in the flowchart of FIG. And / or rewriting to the control constant becomes possible.
For example, if the version of the control constant is older than the version of the control program, the control program can be operated normally by rewriting the version of the control constant corresponding to the version of the control program.

  According to the above embodiment, the flash rewrite program (memory rewrite program) is executed based on the version mismatch without determining the rewrite request from the flash writing tool 5 side. Even if the system does not operate normally, it can be rewritten by running the flash rewrite program.

Therefore, even if the version is rewritten to a control constant whose version does not match, the control abnormality / rewriting cannot be performed, and the automobile electronic control device 1 does not need to be replaced.
Further, even if a control error occurs due to a version mismatch, there is no need to enable rewriting by inputting a signal to the boot pin, so there is no need to provide a boot pin, and the waterproof electronic electronic control device 1 with a waterproof specification, for example, is deleted. In this case, it is not necessary to replace the apparatus due to version mismatch.

For example, when there are a plurality of control constant versions that can be adapted to the version of the control program, if it is one of the plurality of conforming versions, this is naturally regarded as conforming, There is no need to rewrite.
Also, when the flash rewrite program is executed due to a mismatch between the control constant and the control program version, information on the version to be written to the flash memory 2 can be transmitted to the flash writing tool 5 and displayed. it can.

The system diagram of the electronic controller for vehicles in an embodiment. The flowchart which shows the rewriting process in embodiment. 6 is a flowchart showing execution processing of a flash rewrite program based on version determination in the embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electronic control apparatus for motor vehicles, 2 ... Flash memory, 3 ... RAM, 4 ... Microcomputer, 5 ... Flash writing tool, 7 ... Operation apparatus, 8 ... Detection apparatus

Claims (5)

A non-volatile memory capable of electrically erasing and writing data, and an automotive electronic device comprising a non-volatile memory in which a memory rewrite program, a control program, and control constants used for the control program are stored in respective areas A control device,
An electronic control apparatus for an automobile which determines conformity between the control program and the control constant at startup, executes the control program when it conforms, and executes the memory rewrite program when it does not conform .   2. The automobile electronic device according to claim 1, wherein the control program and the control constant each have identification information, and matching of the control program and the control constant is determined by collating the identification information. Control device.   3. The electronic control apparatus for an automobile according to claim 2, wherein the identification information in the control program and the control constant is version information.   The memory rewriting program is executed when the control program and the control constant do not match, and the memory rewriting program is also executed when the writing of the control program and / or the control constant is not normally completed. The automobile electronic control device according to any one of claims 1 to 3.   5. The communication program according to claim 1, wherein the memory rewriting program communicates with an external rewriting tool connected to the automobile electronic control device to rewrite the control program and / or the control constant. The electronic control apparatus for motor vehicles described in any one.

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