JPS622306A - Abnormality detecting device for electronic control unit - Google Patents

Abstract

PURPOSE:To diagnose effectively and efficiently such a defective part as a hardware and a software by executing a rough diagnosis of an electronic control unit by the first monitor means, and dividing and searching an abnormal part of the inside by the second and the third monitor means. CONSTITUTION:An output signal is generated to a signal line 1a from a spurious sensor signal setting part 21, and supplied to an inputting circuit 11 of an electronic control device 10. Next, an output signal from an outputting circuit 13 of the device 10 is measured by an output signal measuring part 24, and an abnormal state of the device 10 is estimated roughly. When an output for satisfying the specifications is not obtained, a port input/output signal is monitored by a port input/output part monitor part 22 through signal lines 3a, 4a. Also, a data signal of a RAM 14 is monitored by a RAM value monitor part 23 through the signal line 4a. Based on these monitor results, a failure part of end internal state of the device 10 is estimated.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to the design of an electronic control device incorporating a process unit such as a microcomputer, for example.
The present invention relates to an abnormality detection device for an electronic control unit that is effectively used on a test bench during development to diagnose abnormal conditions such as input/output circuit failures, mismatching, and program failures.

[Background Art] In the process of designing and developing electronic control devices using microcomputers, etc., it is important to check whether the input/output circuits are operating without any failure or not, and whether there are any abnormalities in the setting program. It is necessary to diagnose whether or not. It is known that diagnosis of such a control unit is performed by, for example, providing a pseudo sensor signal to the control unit and monitoring the output signal of the control unit. Specifically, if this control unit is used as an engine control unit, the pseudo signals include an engine intake air amount signal, an engine rotational speed signal, a throttle opening signal, a cooling water temperature signal, and an air-fuel ratio signal. etc., and measures the fuel injection amount signal output from the control unit. and,
It is determined whether or not this control unit operates normally without any trouble by observing whether or not a fuel injection amount signal having a value corresponding to the above-mentioned pseudo signal is generated.

In other words, if a predetermined pseudo sensor signal is supplied to the control unit, and the expected output signal is not output from this control unit, the hardware of this control unit is defective, or the software is defective. I try to use my intuition to find out whether it is the fault or whether some other part is defective. For this reason, it is extremely difficult to perform accurate diagnostic work, and a great deal of time and effort is required to detect a specific defective location.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned points. Therefore, it is possible to easily and easily control an electronic control unit such as an engine control unit configured using a microcomputer. It enables reliable diagnosis, and in particular, when a defective location exists, it ensures that the defective location is detected with specificity and is used as a test bench when designing or developing such a control unit. It is an object of the present invention to provide an abnormality detection device for an electronic control unit that can be effectively used in the following.

[Means for Solving the Problems] That is, in the abnormality detection device for an electronic control device according to the present invention, a test The first monitoring means detects the output signal of the control unit while the pseudo sensor signal is set to be supplied, and the presence of a rough defective location in the control unit is estimated. second and third detecting signals supplied from the unit to the output circuit and signals supplied from the input circuit to the process unit, respectively, for determining the presence of a defect in the output circuit and the input circuit; It is provided with a monitor means, and the diagnosis of the electronic control unit is executed by the first to third monitor means.

[Operation] In the abnormality detection device configured as described above, the first
An abnormality in the output circuit can be determined based on the rough monitoring result by the above-mentioned monitoring means and the monitoring result by the second monitoring means, and the input circuit can be diagnosed based on the pseudo signal and the monitoring result by the third monitoring means. will be carried out. That is, based on the monitoring results by the first to third monitoring means, it is possible to distinguish and search for abnormal locations inside the electronic control unit.
This makes it possible to effectively and efficiently diagnose not only hardware but also software defects.

[Embodiments of the invention] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a case where a diagnosis is executed to confirm the existence of an abnormality in an electronic control unit 11 constituting an engine control unit, for example, and the electronic control unit I
A diagnostic control device 20 is set for O to execute a diagnostic operation.

The diagnostic control device 20 includes a pseudo sensor signal setting section 21 that generates a pseudo signal for diagnosing the control device 10, and the sensor pseudo signal generated from the signal setting section 21 is transmitted through the signal line 1a. The signal is supplied to the input circuit 11 of the control device 10 via. This control device 10 includes a process unit 12 to which the signal input to the input circuit 11 is supplied, and this unit 12 executes a predetermined arithmetic operation based on the human power sensor signal and uses the result of the arithmetic operation. A corresponding output signal is taken out as an output signal of this control device 10 via the output circuit 13, and output as a control drive signal to the actuator 30 that is the controlled object.

Here, the process unit 12 is provided with a RAM 14 as a storage device for storing data signals and the like used in correspondence with arithmetic operations.

The diagnostic control device 20 further receives signals from a port human output signal monitor section 22 and the RAMI 4, which are supplied with output signals from the input circuit 11 and human signals to the output circuit 13 via signal lines 2a and 3a, respectively. RAM value monitor section 23 detects via signal line 4a
, further includes an output signal measuring section 24 that detects the detection signal of the control device 10 via the signal line 5a. Then, the signal setting section 21, the monitor section 22, 23, and a total of 71
The 11 section 24 is driven and controlled by a control section 25 connected and set via an internal bus 27. A console 26 is set up for this control section 25 .

The pseudo sensor signal setting section 21 includes an electronic control device IO
Specifically, it generates analog signals such as voltage, current, and resistance, digital signals such as switch signals, and pulse-like signals such as engine rotational speed signals.

FIG. 2 shows a specific configuration example of this pseudo sensor signal setting section 21, in which a digitization/signal output circuit 211 outputs a digital signal as described above, and an analog signal output circuit 211 outputs an analog signal as well. output circuit 212,
It further includes a pulse output circuit 213, and output signals from each of these output circuits 211 to 213 are supplied to the input circuit 11 of the control device 10 via the signal line la. Each of the input circuits 211 to 213 is connected to the internal bus 27 via the bus interface circuit 24.

FIG. 3 shows a specific configuration example of the port human output signal monitor section 22, in which digital signals such as switch signals corresponding to the pseudo sensor signals from the signal lines 2a and 3a, and output signals from the process unit 12 are shown. A digital input circuit 221 to which signals such as digital drive signals are supplied; an analog measurement circuit 222 to which analog input signals are supplied; and a pulse measurement circuit to which pulse signals such as engine rotation signals and actuator drive signals are supplied. A circuit 223 is provided. And these input circuits 21
1. The circuits 222 and 223 d1 are connected to the internal bus 27 via the bus interface circuit 224.

Further, the RAM value monitor section 23
4, and as shown in FIG. 4, addresses and data are supplied via signal line 4a, and are supplied to address buffer 2311 and data buffer 232, respectively. The write/read command signal WR is also supplied.
This command signal is supplied to the RAM 234 together with the signals input to each of the buffers 231 and 232. And this dual port RAM
234 is connected to the internal bus 27 via a bus interface circuit 235.

The output signal measuring section 24 is supplied with digital, analog signals, and pulse signals of the control device 1O supplied via the signal line 5a, as shown in FIG.
Digital input circuit 241. It includes an analog meter 7II+1 circuit 242 and a pulse measurement circuit 243. Also,
An abnormal output detection circuit 244 is provided to detect an abnormality in the actuator drive pulse or the like. and,
These circuits 241 to 244 are connected to the internal bus 27 via a bus interface circuit 245.

The control unit 25 uses the pseudo sensor signal setting unit 21, the monitor units 22 and 23, and the output signal measurement unit 24 to detect an abnormality in the electronic control device IO, that is, to estimate the location of the failure. . Therefore, the CPU 25 configured to be connected via the data bus 251
2. It is equipped with a memory 253, and a console 26 is connected via a console interface 254.

The bus 251 is connected to the bus interface circuit 2.
55 to connect to the internal bus 27.

The console 26 is used to give commands to the control section 25 and to display the results of detection of abnormalities in the control section 10 from the control section 25.

That is, in the abnormality detection device configured as described above, the memory 25 of the control unit 25 of the diagnostic control device 20
3, an inspection program based on the specifications of the control device 10 to be tested is stored in advance. Then, based on commands from the console 26, an abnormality in the control device 10 is detected, that is, the location of the problem is estimated.

The test conditions for the control device 10 are given to the input circuit 11 of the control device 10 from the pseudo sensor signal setting section 21 via the signal line 1a, and the test conditions for the control device 10 corresponding to this human input signal are 10 output signals are
The signal is set to be supplied to the output signal needle 11F1 portion 24 via the signal line 5a. In addition, the signal line 2a
The internal state of the control device 10 is monitored by the port output signal monitor section 22 and the RAM value monitor section 23 based on the signal taken out through 4a.

FIG. 7 shows the flow of processing for supplying the test condition signal as described above to the control device 0 and executing the abnormality detection operation of the control device 10. First, in step 41, the test conditions are set. do. That is, an output signal is generated from the pseudo sensor signal setting section 21 to the signal line 1a, and is supplied to the input circuit 11 of the control device 10. In this way, the output signal ``is taken out from the control device 10 in a state where the predetermined pseudo sensor signal is set to be supplied to the device under test 10, but in step 42
The output signal taken out from the signal line 5a is measured by the output signal measuring section 24. Then, in the next step 43, it is determined whether or not an output satisfying the specifications has been obtained, and the abnormal state of the control device 10 is roughly estimated.

Then, if a satisfied specification is obtained, this process ends. If an output that satisfies the specifications cannot be obtained, the process proceeds to the next step 44, where the monitor section 22 monitors the port output signal. Further, in step 45, the RAM data signal input to the monitor unit 23 is monitored, and in the next step 4B, a defect location is estimated based on the monitoring results in steps 44 and 45 described above. This estimation result is displayed on the console 26 in step 47.

Here, the estimation of the distribution location in step 4G is performed in four steps 461 to 4 as shown in FIG. 8, for example.
Execute with 04. First, in the estimation in step 461, a rough estimation is performed based on the measurement result of the output signal of the control device 10. For example, if the control device 10 constitutes an engine control unit and generates an output signal for controlling the fuel injection amount, the control device 10 generates an output signal that controls the amount of fuel injection, and when a pseudo sensor signal is applied, the control device 10 generates an output signal that controls the amount of fuel injection. An injection command signal will now be output.

The estimation in step 461 in such a setting state is executed in the state shown in FIG. 9. For example, as shown in 1-1, the output signal from the control device ”, the digital input section or pulse input section in the input circuit 11 of the control device 10, the driver section in the output circuit 13, or the built-in program, as shown by the Δ mark in this figure. It is estimated that there is a possibility that a problem has occurred in one of them. Similarly,
As shown in 1-2 to 1-5, depending on the output monitoring results such as ``No injection,'' ``Large error in injection time,'' ``Injection amount is correct,'' and ``Abnormal injection,'' the corresponding estimation is made. It is something that is done.

Next, in step 462, the signal at the output port of the process unit 12 of the control device 10 is monitored to improve the rough estimate in step 461 to a more accurate estimate. Specifically, if the output port remains off as shown in Figure 9, this indicates that there is an abnormality in either the digital input, pulse input, or built-in program. Yes, there are 3 parts with a possibility of failure based on the rough estimation result in step 461 above.
The estimated locations are narrowed down.

Additionally, if the port output remains on, it indicates that the built-in program is normal, and if the port output exists, it indicates that the driver is normal. If this has been done, the defect location estimation process ends at step 462.

Then, in step 463, the input port signal of the process unit 12 of the control device 10 is monitored.
1 to 3-3 are performed to make the estimation in step 462 more accurate.

Namely. The estimation of the fault location is completed in this step 463. If the fault location cannot be estimated even in this step 463, the next step 464 is executed and the result of monitoring the value of RAM 14 in the control device 10 is This allows us to estimate the bug location in the program. When such estimation processing is completed, the control unit 25 outputs the result to the console 2B, and displays the result as shown in FIG. 10, for example.

That is, in the abnormality detection device configured as described above, the control device 10 is connected to the input circuit 1 without viewing the control device to be detected as a single black box.
1, process unit 12, output circuit 13, and RA
It is viewed as consisting of four parts of the RAM 14, and monitors and measures the input/output signals to the process unit 12 and the RAM 14 together with the output signals of the control device IO. be. Therefore, the location of the problem in the control device IO can be estimated in more detail based on empirical rules programmed in advance in the internal circuit or internal program. In other words, the detection of a malfunction in the electronic control device IO can be performed in a shorter time with higher accuracy.

In addition, in the electronic control device IO, if there are almost no bugs in the built-in program, or if there is a bug but a detailed estimation of the location of the bug is not required, the configuration shown in FIG. 11 is used. Good too. That is, from the embodiment shown in FIG.
The value monitor section 23 is removed. In addition, in this figure, the same components as in FIG. 1 are indicated using the same reference numerals.
The explanation will be omitted.

That is, in the case of the above-mentioned state, even if configured as shown in this embodiment, it will function as a sufficient abnormality detection device for the control device 10.

[Effects of the Invention] As described above, according to the abnormality detection device for an electronic control device according to the present invention, an abnormal state of an electronic control unit configured using a microcomputer or the like can be detected using a pseudo sensor signal. It is possible to estimate and diagnose a malfunction location in sufficient detail in the supplied state, and it can be effectively used in the design and development process of such a control unit.

[Brief explanation of drawings]

FIG. 1 is a block diagram illustrating an abnormality detection device according to an embodiment of the present invention, FIGS. 2 to 6 are block diagrams showing each circuit section used in the above embodiment, and FIG. 8 is a flowchart explaining the process flow of the abnormality detection device, FIG. 8 is a flowchart explaining the abnormality estimation step in the process flow, FIG. 9 is a diagram explaining the state of the abnormality estimation step, and FIG. The figure shows an example of the display state of diagnosis results, and FIG. 11 is a configuration diagram showing another embodiment of the present invention. IO...Electronic control device, 11...Input circuit, 12
...Process unit, 13...Output circuit, 14.
... RAM, 20... Diagnosis control device, 21... Pseudo sensor signal setting section, 22... Port human output monitor section,
23... RAM value monitor unit, 24... Output signal measurement unit, 25... Control unit, 26... Console. Applicant's Representative Patent Attorney Takehiko Suzue Figure 1 Figure 3 Figure 5 Fupe Figure 6 Figure 7

Claims (1)

[Claims] Means for supplying a pseudo sensor signal to an input circuit of an electronic control unit to detect an abnormality; and means for detecting an output signal of the control unit to which the pseudo sensor signal is supplied, a first monitor means for performing estimation; a second monitor means for detecting a signal supplied from the process unit of the control unit to the output circuit and determining the quality of the output circuit; An abnormality detection device for an electronic control unit, comprising: third monitoring means for detecting a signal supplied from an input circuit to the process unit and determining whether the input circuit is good or bad.