JP3498930B2 - Automotive electronic control device with automatic inspection function and inspection device therefor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile electronic control device, and more particularly to an automobile electronic control device having an automatic inspection function for automatically executing an inspection program and its inspection device.

[0002]

2. Description of the Related Art As is well known, various electronic control devices for automobiles have been developed which control various devices mounted in automobiles using a microcomputer, such as internal combustion engines, brakes, car audios, and meters. Such an electronic control unit for an automobile carries out signal processing by digital signals, and it is difficult to inspect whether the function thereof is correctly maintained and executed only by monitoring the voltage or current of each part. Furthermore, it can be said that it is impossible to perform a sufficient inspection after the electronic control unit for an automobile is mounted.

Therefore, in addition to the usual control routine programs, a test routine program is loaded in the microcomputer in advance, and when a predetermined condition is satisfied, an electronic control unit for an automobile which executes the test routine is disclosed in Japanese Patent Publication No. No. 63-58735. In the device disclosed in the above publication,
As the above-mentioned predetermined condition, the time when the controlled object is in an abnormal state which cannot occur in the normal operation is mentioned.

As an abnormal state that cannot occur during normal operation, an extremely high speed rotation of about 9000 rpm which cannot occur in an actual engine, an extremely high temperature and an extremely low temperature state, and a state that cannot occur at the same time, for example, a transmission. As for the gear shift position of, both the top and the neutral are in the shift position. When inspecting an automobile control device having such an automatic inspection function, the inspection is performed by supplying a pseudo parameter signal to an input circuit of the automobile control device to execute a test routine in the microcomputer. .

However, when such a conventional automobile control device is mounted on an actual machine, not only the engine parameters such as the internal combustion engine speed of the automobile, intake air amount, engine temperature, throttle opening, manifold negative pressure, When a sensor for detecting so-called running parameters including running speed inclination signal, etc. fails, an output signal indicating an abnormal state such as ultra-high speed, ultra-high temperature, etc. is supplied to the microcomputer, and the microcomputer performs a test. If the routine is executed and the original control program of the automobile is stopped, a problem may occur.

[0006]

SUMMARY OF THE INVENTION Therefore, the present invention provides an electronic control unit for an automobile equipped with an automatic inspection function that does not execute a test routine even if the running parameter sensor becomes abnormal. To aim.

[0007]

In order to achieve the above-mentioned object, the present invention is an electronic control unit for an automobile including a microcomputer provided with an inspection routine program and an automobile control routine program. as storage means includes a backup RAM battery voltage to maintain as long as the storage function of being supplied, the microcomputer, upon detecting Iguni' sucrose down switch-on information, the test flag is written in a predetermined address of the backup RAM Whether the test flag is written or not, and a means for executing the inspection routine when the first determination means determines that the test flag has been written, and the first determination means for performing the test. If the flag is determined to be not yet written, the self The execution of the car control routine program
Second permitting means that determines whether or not a test flag write command is supplied by an operation while permitting the operation;
An electronic control unit for an automobile is provided, which comprises: writing means for writing the test flag to the predetermined address of the backup RAM when the determination means determines the supply of the test flag write command.

[0008]

1 is a block diagram of an electronic control unit ECU for an automobile according to the present invention and an inspection device T for inspecting the same.
It shows a state in which ST is connected by a connector CNN. The inspection device TST receives a battery voltage that is substantially equal to the on-vehicle battery voltage via the power supply terminal B, and relays this to the power supply output terminal BTT. Further, the power supply circuit 1 steps down the battery voltage to make it a constant voltage and supplies it to an electronic circuit such as the microcomputer 2. Microcomputer 2
Is composed of a CPU (central processing unit), a ROM and a RAM (not shown), and the RO is provided in response to various command inputs by the operator from the keyboard 3 as command input means.
A predetermined operation is performed by executing the program stored in M or RAM.

When the microcomputer 2 receives the inspection start command via the keyboard 3, the microcomputer 2 sends the ignition on command to the ignition switch I.
Supply to GSW to turn it on. When the IGSW is turned on, the battery voltage is supplied to the terminal IGE of the ECU via the terminal IGT. The communication unit 4 has terminals CT1,
EC via CT2 and terminals CE1 and CE2 on the ECU side
It is connected to the communication unit 10 in the U. Therefore, the microcomputer 2 in the inspection device TST and the microcomputer 11 in the ECU are connected to the communication units 4, 10
Communication can be performed by transmitting and receiving serial data via the. Further, the input / output interface circuit 5 in the TST of the inspection device is connected to the input / output interface circuit 12 in the ECU via the connector CNN. Therefore, the microcomputer 2
It is possible to supply a pseudo parameter signal to the microcomputer 11 and monitor the output of the microcomputer 11 via the input / output interface circuits 5 and 12. Further, the inspection device TST includes a display device 6 such as a CRT which is controlled by the microcomputer 2 and which displays various information such as an inspection result so that the operator can view the information.

In the ECU, the power input terminal BTE
The battery voltage supplied via the power supply circuit 13 is stabilized by the power supply circuit 13 and supplied to the backup RAM 14. Further, in the ECU, the power supply circuit 15 has the input terminal I
The ignition-on voltage supplied via the GE is stepped down and stabilized to obtain a power supply voltage, which is supplied to the microcomputer 1
It is designed to supply one.

With such a configuration, the microcomputer 11 is activated only when the ignition-on voltage via the terminal IGE, that is, the battery voltage is supplied, and executes the normal control subroutine as will be described later. The test routine is executed under predetermined conditions. Next, the operations of the vehicle electronic control unit ECU and the inspection device TST shown in FIG. 1 will be described with reference to the flowchart of FIG.

First, when the worker completes the connection between the ECU and the TST with the connector CNN, the battery voltage is supplied to the power supply circuits 1 and 2, and the preparation is completed. In this state, when the operator operates the keyboard 3 and inputs an inspection start command, the microcomputer 2 commands the ON of the ignition switch IGSW to turn it on. Then, the microcomputer 11
Performs the routine of FIG. 2 in accordance with clock pulses provided by an internal oscillator (not shown).

That is, first, when the ignition switch ON voltage is detected, the microcomputer 11 sets the initial values of the running parameters necessary for executing various programs,
Etc. are initialized (step S1). Then, it is determined whether or not the test flag F is written as 1 at a predetermined address of the backup RAM 14 (step S).
2). If F = 1 is determined, the test routine is immediately executed (step S3). This test routine is, for example, a routine executed by a program similar to the check program described in Japanese Patent Publication No. 63-58735, but the details thereof will not be described here. When the execution of this test routine is completed, F is set to 0 (step S4), and the process returns to the upstream of the normal control routine (step S5). However, normally, immediately after the initialization, F = 0, and the microcomputer 11 executes the normal control routine (step S5). In this case, a pseudo signal such as a traveling parameter is supplied to the input / output interface 12 via the input / output interface 5. When the execution of the normal control routine ends, it is determined whether or not the test flag write command is supplied from the microcomputer 2 via the communication units 4 and 10 (step S6).
The microcomputer 11 may fetch the writing of the test flag write command in advance by a subroutine (not shown).

When it is determined in step S6 that the test flag write command is supplied, F ← 1 is written to a predetermined address of the backup RAM 14 (step S7). In this state, the inspection device TST
The microcomputer 2 first orders the turning off of the IGSW, and then orders the turning on of the IGSW again. Then, the microcomputer 11 executes the routine of FIG. 2 again. Since F = 1 in this case, the test routine is executed (step S3).

As described above, according to the vehicle electronic control apparatus of the present invention, when the ignition switch-on voltage is received, the routine shown in FIG. 2 is repeatedly executed. In this routine, the inspection device TST is executed.
The test execution flag F is held in the backup RAM that holds the stored contents in the presence of the battery voltage supplied from the.

Therefore, when inspecting the electronic control unit for an automobile by the inspection device, if the test flag write command is supplied from the inspection device through the communication units 4 and 10, the test routine is executed only once. . Then, the electronic control unit ECU for the vehicle is temporarily set to the inspection device TS.
When separated from T, the contents of the backup RAM 13 are F
The test routine is not executed unless the inspection device TST is connected again and the battery voltage is supplied and the test flag write command is supplied.

Incidentally, the microcomputer 2 in the inspection apparatus TST, by a predetermined command from the keyboard 3,
Alternatively, the predetermined time from the inspection start command is timed, and the above-described test flag write command is transmitted via the communication units 4 and 10 to the microcomputer 1 in the ECU.
Supply to 1. Note that steps S6 and S7
It is conceivable that there is a modification in which is executed immediately before the normal control routine (step S5), and further, step S6.
It is also possible to make a modification such that steps S7 and S7 are executed during the normal control routine (step S5). FIG. 3 shows another example of a routine to be executed by the microcomputer according to the present invention.

That is, after the inspection device TST is connected to the automobile electronic control unit ECU which is the device to be inspected by the connector CNN, when the inspection start command is given by the keyboard 3, the IGSW is turned on after a predetermined time and the ignition switch voltage is changed. It is given to the power supply circuit 15, and the power supply circuit 15 steps down this voltage and supplies it to the microcomputer.

As a result, the microcomputer 11
The execution of the flow of FIG. That is, first, initialization such as initial value setting of traveling parameters necessary for executing various programs is performed (step S1). Then, it is determined whether or not the test flag F1 is written as 1 at a predetermined address of the backup RAM 14 (step S2). If F1 = 1 is determined, the test routine is immediately executed (step S
3). When the execution of this test routine is completed,
F1 is set to 0 (step S4), the test end flag F
2 is set to 1 and the process returns to the upstream of step S2 (step S1
0).

If it is determined in step S2 that F1 = 0, it is determined whether the test end flag F2 is 1 (step S11), and F2
When it is determined that = 1, it is determined whether or not the interrupt flag for the normal control subroutine is set (step S12), and if it is set, the normal control subroutine is executed (step S13). If no interrupt flag is set, go to step S
It returns to the upstream of 2 and repeats this routine until the IGSW is turned off.

On the other hand, if it is determined in step S11 that the test end flag F2 is zero, it is determined whether or not a test flag write command is input (step S14). When it is determined that the test flag write command is input, F1 is set to 1 and
This is written in a predetermined address of the backup RAM (step S15).

As described above, according to the electronic control unit for an automobile of the present invention, when the information of the ignition switch-on is received, the main routine shown in FIG. 3 is repeatedly executed, and in this routine, the inspection is performed. The test execution flag F1 and the test end flag F2 are held in the backup RAM that holds the stored contents in the presence of the battery voltage supplied from the device TST.

Therefore, when inspecting the electronic control unit for an automobile by the inspection device, if the test flag write command is supplied from the inspection device through the communication units 4 and 10, the test routine is executed only once. . Then, once the you <br/> switching RiHanare the automotive electronic control unit from the inspection apparatus TST contents of the backup RAM13 is a initialized F1 = 0, F2 = 0, connect the inspection device TST again The test routine is not executed unless the inspection procedure described above is executed.

The inspection device TST may display the inspection result after receiving the inspection end information such as the test end flag from the vehicle control unit ECU.

[Brief description of drawings]

FIG. 1 is a block diagram showing an electronic control unit for a vehicle and an inspection apparatus for the same according to the present invention.

FIG. 2 is a flowchart showing a subroutine to be executed by the electronic control unit for an automobile according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing a routine to be executed by a vehicle electronic control unit according to a second embodiment of the present invention.

[Explanation of symbols for main parts]

TST inspection device ECU Electronic control unit for automobile CNN connector IGSW ignition switch

Continuation of front page (56) Reference JP-A-7-43255 (JP, A) JP-A-62-188933 (JP, A) JP-A-1-301139 (JP, A) JP-A-8-76830 (JP , A) JP-A-8-75616 (JP, A) JP-A-7-175502 (JP, A) JP-A-6-102148 (JP, A) JP-A-63-228081 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G05B 19/048-19/05 G01M 17/00-17/007

Claims (6)

(57) [Claims] 1. A vehicle control apparatus including a microcomputer provided with an inspection routine program and an automobile control routine program, wherein the microcomputer has a storage means that maintains a storage function as long as a battery voltage is supplied. has a RAM, the microcomputer, upon detecting Iguni' sucrose down switch-on information, the first determination means that the test flag is determined as soon as being written in a predetermined address of said backup RAM, wherein the first determination means Means for executing the inspection routine when it is determined that the test flag is written, and the vehicle control routine program when the first determination means determines that the test flag is not yet written. Allowed to run
On the other hand, when the test flag writing command is supplied by the operation and the second judging means determines that the test flag writing command is supplied, the predetermined judgment of the backup RAM is performed. A writing means for writing the test flag at an address, and a vehicle control device. 2. The vehicle control device according to claim 1, wherein the microcomputer receives the test flag write command via a data communication unit. 3. The inspection device for a vehicle control device according to claim 1, wherein when connected to the vehicle control device, a first means for supplying a battery voltage to a battery voltage terminal of the vehicle control device. And second means for supplying an ignition-on voltage to an ignition switch-on terminal of the vehicle control device, and third means for supplying the test flag write command to the microcomputer. Inspection device. 4. The inspection apparatus according to claim 3, wherein the third means supplies the test flag write command via a data communication means. 5. The second means temporarily stops the supply of the ignition on voltage after the test flag write command is generated by the third means, and then supplies the ignition on voltage to the vehicle controller again. The inspection apparatus according to claim 3, wherein: 6. A fourth means for supplying a pseudo parameter signal to the vehicle controller and fetching an output signal from the vehicle controller after the test flag write command is supplied by the third means. The inspection device according to claim 3.