JP2001182607A - Vehicle controlling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle controlling device for preventing useless writing. SOLUTION: An ECU 1 is equipped with a CPU 2, ROM 3, N.RAM 4, S.RAM 5, and EEPROM 6, and controls a vehicle with voltage VIG supplied by charging the ignition switch 21 of the vehicle, to calculate a learning value by learning control at the time of the vehicle control. By the CPU 2, the writing, into the EEPROM 6 of the learning value calculated by the learning control, is prohibited when the abnormality of the vehicle is warned by the lighting of a warning lamp 19, and is performed when the lamp 19 is not lit, the vehicle is driven 10 times or more from the preceding written time, and a vehicle speed (v) becomes 40 km/h or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle control device for controlling a vehicle, and more particularly, to a vehicle in which a learning value calculated by learning control is stored in an electrically rewritable nonvolatile memory. The present invention relates to a control device.

[0002]

2. Description of the Related Art Conventionally, in a vehicle control apparatus for controlling an engine or an automatic transmission (automatic transmission) of a vehicle, a past control result is evaluated in order to eliminate influences such as a temporal change of an object to be controlled and individual differences. So-called learning control, which modifies control parameters and control logic, is widely adopted. There is known a device that stores a learning value such as a control parameter obtained by the learning control in a nonvolatile memory (for example, an EEPROM) in which data can be electrically rewritten (for example, Japanese Patent Laid-Open No. 10-25 / 1998).
No. 2547). In this type of device, when it is determined that the battery has been disconnected, the learning value is transferred from the nonvolatile memory to the normal RAM so that the learning value calculated in the past can be used continuously.

In the device disclosed in Japanese Patent Application Laid-Open No. 10-252547, operating power is supplied when an ignition switch of a vehicle is turned on, and the vehicle is driven at a predetermined speed (40 kV).
m / h) or more, a process of writing a learning value (learning data) to the EEPROM is performed.
In other words, when the vehicle is running, the possibility that the vehicle driver turns off the ignition switch is extremely low,
Moreover, that state is expected to continue for a while. Therefore, when the vehicle is running at a predetermined speed (40 km / h) or more, the process of writing the learning value to the EEPROM is started.

In the apparatus disclosed in Japanese Patent Application Laid-Open No. H10-252547, a writing process to the EEPROM requires several hundred milliseconds to write tens of bytes of learning data. When the switch is turned off and the operating power is cut off, the writing process is interrupted. Therefore, when the next ignition key is turned on (turned on), it is determined whether or not the previous writing to the EEPROM has been completed normally. When it is determined that the writing has not been completed, the writing process to the EEPROM is performed again. It is supposed to.

[0005]

Usually, when the vehicle is running at a predetermined speed (40 km / h) or more, there is almost no possibility that the ignition switch is turned off. Abnormal diagnosis)
Therefore, when the abnormality of the vehicle is detected and the warning lamp is turned on, the behavior of the driver cannot be predicted. Specifically, as shown in FIG. 5, the vehicle speed becomes equal to or higher than a predetermined speed (40 km / h) at the timing of t1, the EEPROM writing process is started, and the learning value writing process is performed at a predetermined time T. At that time, there is a possibility that the driver turns off the ignition switch by turning on the warning lamp. As a result, the operating power is shut off, and the EEPROM
The process of writing the learning value to the memory is interrupted (timing of t2). In this case, when the engine is started again by turning on the ignition switch, the previous E
The writing to the EPROM is determined to be incomplete, and t
When the speed becomes equal to or higher than the predetermined speed (40 km / h) at timing 3, the EEPROM writing process is started again. Thus, the lighting of the warning lamp causes the EEPROM
Is interrupted, the processing time and the number of times for writing to the EEPROM are increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problem, and an object of the present invention is to provide a vehicle control device capable of preventing useless writing.

[0007]

According to the first aspect of the present invention, when the power switch of the vehicle is turned on, the operating power is supplied to control the vehicle, and the learning value is calculated by the learning control during the vehicle control. Is done. When the predetermined write condition is satisfied, the learning value is written to the nonvolatile memory. However, when the abnormality warning unit warns the abnormality of the vehicle, the write to the nonvolatile memory is prohibited (write operation). Does not start). As a result, useless writing can be prevented.

That is, it takes a predetermined time to write the learning value to the nonvolatile memory, and if the power is turned off during the writing, the learning value is written again. Therefore, if writing to the nonvolatile memory is prohibited at the time of a vehicle abnormality warning, useless writing processing that is interrupted halfway by turning off an ignition switch by turning on a warning lamp as in the related art is not performed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a vehicle engine control system will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of an electronic control unit (ECU) 1 as a vehicle control unit. As shown in FIG. 1, the ECU 1 includes a CPU 2, a ROM 3, a normal RAM (hereinafter, referred to as N-RAM) 4, a standby RAM (hereinafter, referred to as N RAM).
5) and an EEPROM 6. The CPU 2, the ROM 3, the N-RAM 4, and the S-RAM 5 are connected to each other via the bus 7,
U2 and EEPROM 6 are connected by serial data line 8.

The CPU 2 executes various processes for controlling the vehicle-mounted engine according to a program stored in the ROM 3 in advance. The N.RAM 4 is a RAM for calculation work for temporarily storing a result of control calculation by the CPU 2, and is not backed up by a battery voltage. On the other hand, the S-RAM (also referred to as a backup RAM) 5 is provided with a power supply backup by a battery voltage, and is supplied with power even when the ignition is turned off and retains stored data. Further, the EEPROM 6
It is a non-volatile memory that can electrically rewrite data, and retains stored data even when power is turned off.

Further, the ECU 1 includes an input circuit 11, an output circuit 12, and a power supply circuit 13. Input circuit 1
1 is connected to a speed sensor 15 for detecting the speed NE of the engine, a vehicle speed sensor 16 for detecting the running speed (vehicle speed) v of the vehicle, and the like. The input circuit 11 outputs to the CPU 2 signals corresponding to the rotational speed NE, the traveling speed (vehicle speed) v, and the like detected by each sensor. Output circuit 1
2 is connected to an injector 17, an igniter 18, a warning lamp 19 as abnormality warning means, and the like. The output circuit 12 includes an injector 17, an igniter 18, and a warning lamp 19 according to a drive signal input from the CPU 2.
And so on.

The power supply circuit 13 is connected to a battery 22 via an ignition switch 21 as a power supply switch, and is supplied with an ignition voltage VIG when the ignition switch 21 is turned on. Thereby, the power supply circuit 1
3 is CPU2, ROM3, N-RAM4, S-RAM
5 and the EEPROM 6 to output the operating voltage VD. The power supply circuit 13 is directly connected to the battery 22 separately from the connection via the ignition switch 21, and is always supplied with the battery voltage VBB. As a result, the power supply circuit 13 outputs the backup voltage VS for data retention to the S-RAM 5.

In such an ECU 1, when the ignition switch 21 is turned on (turned on), the operating voltage VD is supplied from the power supply circuit 13 to the CPU 2, the ROM 3, the N.RAM 4, and the like. Then, the CPU 2
The engine control process is executed in accordance with the program stored in M3, and actuators such as the injector 17 and the igniter 18 are actuated based on sensor signals from the various sensors 15 and 16 to perform known engine control. ing. During engine control, the CPU 2 diagnoses abnormality of various sensors and actuators and abnormality of a wire harness connecting the sensor / actuator to the ECU 1 by diagnosis (vehicle abnormality diagnosis).
Is detected by When the abnormality is detected, the warning lamp 19 is turned on to warn the vehicle driver or the like of the abnormality.

The engine control process executed by the CPU 2 includes learning control. The CPU 2 periodically sends a learning value (several tens of bytes) such as a control parameter calculated on the N-RAM 4 to the S-RAM 5 by the learning control. The learning value is copied so that the learning value is not lost even when the ignition switch 21 is off. Specific learning values include learning data related to the fully closed position of the actuator such as the ISC valve and the EGR valve, and the air-fuel ratio control amount. Further, when a predetermined condition is satisfied, the CPU 2 sets N · R
The learning value on the AM 4 is written to the EEPROM 6, so that the battery 22 is disconnected and the RAM
Even if the storage data of No. 5 is lost, the learning value is not lost.

Here, the EEPROM in this embodiment is
The conditions for writing data to the EEP 6 are as follows:
The engine is started a predetermined number of times (specifically, 10 times) from the time of writing to the ROM 6, and (b) the vehicle speed v is equal to or higher than a predetermined speed (specifically, 40 km / h). It should be noted that the number of engine starts shown in (a) is counted when the ignition switch 21 is turned on and the engine speed actually exceeds a predetermined speed (specifically, 500 rpm). Therefore, the learning value is written into the EEPROM 6 at least every time the engine is started ten times, and the EEPROM is limited in the number of times of writing.
The number of times of writing data to the ROM 6 is reduced.

Next, the processing executed by the CPU 2 of the present embodiment will be described with reference to the flowcharts of FIGS. First, an outline of this processing will be described. In the present embodiment, a start detection flag F1, a write permission flag F2, and a counter C are set in the N.RAM 4 in order to write a learning value to the EEPROM 6. The start detection flag F1 is a flag indicating whether or not the engine is actually started after the ignition switch 21 is turned on.
"1" when the engine speed exceeds 500 rpm
Is set. Then, the value of the counter C is counted at the set timing of the start detection flag F1, and the number of starts of the engine is determined based on the value of the counter C.
The write permission flag F2 is a flag indicating whether or not the writing of the EEPROM 6 is permitted. When the write permission flag F2 is set (= 1), the data is written to the EEPROM 6 so as to be written. Has become.

In the ECU 1 of this embodiment, it takes several hundred milliseconds to write a learning value of several tens of bytes to the EEPROM 6, and during this writing process, the ignition switch 21 is turned off to operate. Voltage V
If D is interrupted, the write process will be interrupted. In this case, when the vehicle is driven again, the previous E
It is determined that the writing to the EPROM 6 is not completed, and the process of writing data to the EEPROM 6 is performed again. Note that data indicating the write state of the EEPROM 6 is set in a predetermined area of the S-RAM 5, and based on this data, it can be determined whether the write state of the EEPROM 6 is an uncompleted state or a completed state. It has become.

The details will be described below. As shown in FIG. 2, when the operation voltage VD is supplied with the turning on of the ignition switch 21 and the operation is started, the CPU 2
The initialization processing of steps 100 to 120 is performed.

Specifically, in step 100, C
PU2 stores the history of battery disconnection (that is, battery 22
Is determined). This judgment is
For example, this is performed by checking the data stored in the S-RAM 5. If the stored data is normal, it is determined that there is no history of battery disconnection, and if abnormal, it is determined that there is a history of battery loss.

If there is a history of battery disconnection, S
・ Data stored in RAM 5 (ignition switch 21
The learning value etc. backed up and stored in the S.RAM 5 while the power is off is indefinite. Therefore, in step 110, the CPU 2 writes the learning value written in the EEPROM 6 at that time into the N · RAM 4, and proceeds to step 120. On the other hand, if there is no history of battery loss, since the data stored in the S-RAM 5 is normally held, the CPU 2 writes the data stored in the S-RAM 5 into the N-RAM 4 in step 115, and proceeds to step 120. Move to

Then, in step 120, the CPU
2 sets the start detection flag F1 to "0" indicating that the engine has not been started yet, and sets the write permission flag F2 to "0" indicating that writing to the EEPROM 6 is not permitted. I do.

After completing the initialization processing in steps 100 to 120, the CPU 2 starts execution of the engine control processing based on the learning control, and concurrently with the engine control processing, as shown in FIGS. Step 130-
The processing of step 290 is repeated periodically (for example, every 16 milliseconds).

More specifically, in step 130, the CP
U2 writes (copies) the learning value currently stored in the N-RAM 4 and the value of the counter C into the S-RAM 5. Then, at step 140, the start detection flag F
It is determined whether or not 1 is “0”. If “1”, the process proceeds to step 150. The CPU 2 determines in step 150
In the embodiment, the engine speed NE detected based on the signal from the speed sensor 15 is equal to a predetermined speed (in the present embodiment, a value near the idle speed 50
0 rpm) is determined.

If the engine speed is 500 rpm or more, it is determined that the vehicle has actually been operated after the ignition switch 21 is turned on, and the program proceeds to step 160.
Proceed to. In this step 160, the CPU 2 increments the value of the counter C by one on the N · RAM4,
In the following step 170, the start detection flag F1 is set to:
"1" indicating that the vehicle has been driven is set, and the routine proceeds to step 180 shown in FIG.

If the CPU 2 determines in step 140 that the start detection flag F1 is "1", or if it determines in step 150 that the engine speed NE is less than 500 rpm, the CPU 2 executes the steps shown in FIG. Go to 180.

In this manner, after the ignition switch 21 is turned on and the operation is started, a negative determination is made in step 150 until the engine speed NE becomes 500 rpm or more, and the engine speed NE becomes 500 rpm or more. Then, it is determined that the engine has actually been started, and the value of the counter C is incremented by one by the processing of step 160. Further, since the start detection flag F1 is set to "1" by the processing of step 170, while the ignition switch 21 is on, a negative determination is made in step 140.
Is no longer incremented. Also, counter C
Is stored in the S-RAM 5 by the processing of step 130, and is written to the N-RAM 4 by the processing of step 115 when the ignition switch 21 is turned on next. Therefore, the value of the counter C becomes equal to the engine speed NE after the ignition switch 21 is turned on.
Every time a condition occurs where
It will be counted up by one.

Returning to the description of the flowchart, step 180 in FIG. 3 corresponds to the above-described processing for determining the write condition (a) of the EEPROM 6, and step 190 is for determining the write condition (b) of the EEPROM 6. The processing is equivalent to JP-A-10-2525
In the device disclosed in Japanese Patent Publication No. 47, these writing conditions (a),
When the condition (b) is satisfied, that is, the engine is started ten times or more from the previous writing of the EEPROM 6, and
When the vehicle speed v becomes 40 km / h, the writing of the learning value to the EEPROM 6 is started. In the present embodiment, even if the write conditions (a) and (b) are satisfied, the warning lamp 19 is turned off. At the time of lighting, writing to the EEPROM 6 is prohibited.

That is, the process of writing the learning value to the EEPROM 6 is performed in steps 250 and 260. At the start of writing, the write permission flag F2 is set to "1" in step 210, and in step 240 Writing is executed by confirming that the flag F2 = 1. On the other hand, when the warning lamp 19 is lit, the processing of steps 210 to 230 is bypassed in step 200, and the write permission flag F2 is not set to "1", and the processing of steps 250 to 280 is not executed. This allows
Writing to the EEPROM 6 is prohibited.

Hereinafter, the processing of FIG. 3 will be described in detail. The value of the counter C is set to a predetermined value (10 in this embodiment).
If this is the case, or if the previous write state of the EEPROM 6 is an incomplete state, an affirmative determination is made in step 180 and the process proceeds to step 190. Then, in step 190, the CPU 2 determines whether or not the vehicle speed v detected based on the signal from the vehicle speed sensor 16 is equal to or higher than a predetermined speed (40 km / h in the present embodiment). Here, if the vehicle speed v is equal to or higher than 40 km / h, the CPU 2 proceeds to step 200 and determines whether or not the warning lamp 19 is lit. If it is determined that the warning lamp 19 is not lit, the CPU
2, the process proceeds to step 210, where "1" is set to the above-mentioned write permission flag F2, and in the following step 220, the value of the counter C is initialized to "0". Then, in step 230, the CPU 2 sets the value indicating the incomplete state as the write state of the EEPROM 6 to the S · RAM 5
The upper predetermined area is set, and the process proceeds to step 240.

In step 240, the CPU 2 determines whether or not the write permission flag F2 is "1". If F2 = 1, the learning value currently stored in the N-RAM 4 is stored in the EEPROM 6 in step 250. Update and write. In this case, writing of one piece of learning data among a plurality of pieces of learning data to be written to the EEPROM 6 is performed. That is, in the present embodiment, the learning data is sequentially written to the EEPROM 6 by performing the process of the step 250 every predetermined time (every 16 milliseconds). Then, the CPU 2 proceeds to step 26
At 0, it is determined whether or not the writing of all learning data has been completed. If it is determined that the writing is in progress,
The subsequent processes are executed by bypassing the processes of steps 270 and 280. On the other hand, when it is determined that the writing of all the learning data has been completed, the process proceeds to step 270. CP
U2 determines in step 270 that the write permission flag F2
Is set to "0", and the process proceeds to step 280, where E
A value indicating a completion state is set in a predetermined area on the S-RAM 5 as a writing state of the EPROM 6.

Then, the CPU 2 executes other subsequent processing, and at that time, as shown in step 290, N · N
The learning value on the RAM 4 is updated by learning control. Thereafter, the process returns to step 130 shown in FIG.
The latest learning value and the value of the counter C which are currently stored in the RAM are written into the S-RAM 5, and the above-described step 140 is performed.
Repeat the subsequent processing.

On the other hand, in step 180 of FIG. 3, it is determined that the value of the counter C is less than 10, and
When the writing state of No. 6 is determined to be a completed state, or
If it is determined in step 190 that the vehicle speed v is less than 40 km / h, or if it is determined in step 200 that the warning lamp 19 is on, the process proceeds to step 240.
In this case, since the write permission flag F2 is not set to "1", a negative determination is made in step 240, and the processing in steps 250 to 280 is bypassed. That is, EEPR
Writing of OM6 is not started.

More specifically, when the writing of the learning value to the EEPROM 6 is completed, the counter C is used as described above.
Is "0", the write permission flag F2 is "0", and the EEPR
The writing state of OM6 is in the completed state. In this case, since a negative determination is made in the process of step 180, “1” is not set in the write permission flag F2. After that, the engine is started ten times and the value of the counter C becomes 10
If the vehicle speed v is less than 40 km / h, a negative determination is made in the process of step 190, so that "1" is not set in the write permission flag F2. Further, even if the value of the counter C becomes 10 and the vehicle speed v becomes 40 km / h or more, if the warning lamp 19 is lit, the step 200 is executed.
Is not determined, the write permission flag F2 is not set to "1". As described above, while “1” is not set in the write permission flag F2, a negative determination is made in step 240, and the processes in steps 250 to 280 are not performed. That is, the writing process of the EEPROM 6 is not started.

If the ignition switch 21 is turned off or the operating voltage VD is cut off by the influence of noise or the like during the writing of the EEPROM 6, the writing is interrupted. In this case, again the ECU
When the engine is driven and controlled by the
Since the write state of M6 remains unfinished, an affirmative determination is made in step 180 of FIG. Then, when the vehicle speed becomes equal to or higher than 40 km / h and the warning lamp 19 is not lit, "1" is set to the write permission flag F2 in the processing of step 210 through the processing of steps 190 and 200. As a result, the processing of steps 250 to 280 is performed, and the writing to the EEPROM 6 is performed again.

As described above, in the ECU 1 of the present embodiment,
When the engine speed NE becomes 500 rpm or more after the ignition switch 21 is turned on,
Every time the engine is started, that is, every time the engine is actually started ten times, it is determined whether or not the vehicle speed v is 40 km / h or more. Then, when the vehicle speed v is determined to be 40 km / h or more and the warning lamp 19 is not lit, the writing of the learning value to the EEPROM 6 is started. On the other hand, when the warning lamp 19 is
Writing of the learning value to 6 is not started. This gives E
Ignition switch 2 during writing to EPROM 6
1 is turned off, and the possibility of the writing being interrupted is reduced.

That is, in the present embodiment, even if the vehicle has been driven more than 10 times since the previous writing and the vehicle speed has become more than 40 km / h at the timing of t1, as shown in FIG. The writing of the learning value to the EEPROM 6 is prohibited by the lighting of. Therefore, even if the vehicle driver turns off the ignition switch 21 at the timing of t2 due to the lighting of the warning lamp 19, the writing of the EEPROM 6 is not interrupted unlike the prior art of FIG. Thereafter, when the abnormality of the vehicle is resolved by repair or the like and the warning lamp 19 is not lit, the vehicle speed becomes 40
When the speed exceeds km / h (timing of t3 in FIG. 4), EEP
Writing of the learning value to the ROM 6 is started.

In this embodiment, the processing in step 200 in FIG. 3 corresponds to the write-inhibiting means. As described above in detail, the present embodiment has the following features.

(1) When the abnormality of the vehicle is warned, the EEPROM 6
Writing is prohibited, so like before,
Lighting of the warning lamp 19 causes the ignition switch 2
No useless write processing that is interrupted halfway by turning off 1 is not performed. That is, the writing to the EEPROM 6 is performed by one writing process without performing the rewriting process, and the processing time and the number of times for writing the EEPROM 6 can be reduced.

The present invention can be embodied in the following forms other than the above. In the above embodiment, step 19 in FIG.
Although the vehicle speed determined with 0 is set to 40 km / h, the value can be set as appropriate. Step 15 in FIG.
The rotation speed (500 rpm) determined at 0 and the predetermined value (10) determined at step 180 in FIG. 3 can also be set as appropriate. Further, the writing condition is not limited to the vehicle speed v being equal to or higher than the predetermined speed, and another condition may be used as the writing condition.

In the above embodiment, the EEPROM is used as the electrically rewritable nonvolatile memory, but a flash memory may be used. However, when the EEPROM 6 in which data is written via the serial data line 8 is used as in the above embodiment, the time required to write the learning value becomes long. In other words, the possibility that the ignition switch 21 is turned off during the writing is increased, so that it is practically preferable to apply the device to the device using the EEPROM 6.

In the above embodiment, the warning lamp 19 is used as the abnormality warning means. However, for example, a warning buzzer for warning an abnormality may be used as the abnormality warning means. Further, although the ECU 1 of the above embodiment controls the engine of the vehicle, other vehicle control devices such as an electronic control device for controlling an automatic transmission can be configured in exactly the same manner. Of course, the present invention may be embodied in a control device for controlling an electric vehicle other than the engine vehicle.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an outline of an ECU according to an embodiment of the invention.

FIG. 2 is a flowchart for explaining an EEPROM writing process.

FIG. 3 is a flowchart illustrating a write process of an EEPROM.

FIG. 4 is a timing chart for explaining a write operation of the EEPROM.

FIG. 5 is a timing chart for explaining a write operation of a conventional EEPROM.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... ECU as a vehicle control apparatus, 2 ... CPU as a write-protection means, 6 ... EEP as a non-volatile memory
ROM, 19: warning lamp as abnormality warning means, 21
... Ignition switch as power switch.

Claims (2)

[Claims] An operation power is supplied when a power switch of a vehicle is turned on to control the vehicle, and a learning value calculated by learning control when controlling the vehicle is set to a predetermined writing condition when a predetermined writing condition is satisfied. In a vehicle control device configured to electrically write data into a nonvolatile memory in which data can be rewritten, abnormality warning means for warning an abnormality of the vehicle based on abnormality diagnosis of the vehicle, and abnormality of the vehicle is warned by the abnormality warning means. When done
A vehicle control device, comprising: write-inhibiting means for inhibiting writing to the nonvolatile memory even when the predetermined writing condition is satisfied. 2. The vehicle control device according to claim 1, wherein the predetermined writing condition is satisfied when at least the vehicle is running at a predetermined speed or higher.