JP3489306B2 - Electronic control unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention
According to the control program and control data stored in the storage means.
The present invention relates to an electronic control device for controlling a predetermined control object.
The control program and control data in the storage means.
The present invention relates to a replaceable electronic control device. [0002] 2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 6-27261.
As disclosed in Japanese Patent Publication No.
Electronically rewrites data as an electronic control unit
(Specifically, data erasing and writing)
A control program for engine control is stored in the read-only ROM.
Data that constitutes the
Rewrites data in ROM such as after it is supplied to the market
One that has been proposed has been proposed. That is, this kind of electronic control device is usually
Is a control composed of data stored in the ROM.
Control of engine etc. according to control program and control data
It controls the target, but an external device prepared separately
When connected and receiving a predetermined rewrite command,
Data (that is, control programs and control data)
Is configured to execute a rewriting process for rewriting.
You. This rewriting process erases data in the ROM.
To the deleted storage area from the external device.
Write new data that comes in
Is done. [0004] According to such an electronic control device,
For example, after supply to the market, the operation content (control
Content) has to be changed
Can be handled very easily. On the other hand, this species
In the electronic control device, the data in the ROM as described above is used.
When rewriting data, erase the contents of ROM once
Therefore, a rewriting program for executing the rewriting process
The program starts on the ROM to be rewritten
I can't. Therefore, the electronic control device disclosed in the above publication is
Specifies a rewriting program for executing the rewriting process in advance.
Although it is stored in the OM, the ROM is rewritten.
When rewriting, the rewriting program in ROM is read
Transfer to a read / write RAM, and
The rewriting program is started on M. [0006] By the way, usually,
More precise control of controlled objects in various electronic control units
To do this, for example, a part of the storage area of the RAM is
Backup area that can retain data even after power supply is stopped
Learning value calculated when controlling the controlled object
Back up data and data for fail-safe
Must be stored in the backup area. In other words, like this
By configuring, the calculated learning value data etc.
The data can be stored continuously after the stop, and based on the data
System that can suppress the effects of time-dependent changes and failures of controlled objects.
Control volume to improve control reliability.
It comes to be. However, in the above-mentioned conventional apparatus, RO
When rewriting data in M, the rewriting program
M to be stored in the backup area
There is a problem of destroying the learned value data
Was. The rewriting process is performed as in the device disclosed in the above publication.
The rewrite program for executing
Rather than rewriting the data in the ROM
Configuration that receives a replacement program from an external device.
It is conceivable that, in this case, too,
Transfer to RAM before starting
Therefore, the above problem similarly occurs. The present invention has been made in view of such a problem.
Data that can be read and written.
Lost data stored in the backup area
Stored in read-only storage
Control programs and control data can be rewritten.
It is an object of the present invention to provide an electronic control device. [0009] Means for Solving the Problems and Effects of the Invention
Claim 1 of the present invention has been made to achieve
The electronic control unit has an electrically rewritable data reader.
First storage means exclusively for reading, reading and writing of data
Writing is possible, and a part of the storage area is supplied with power.
Backup to keep data even after the
Between the second storage means set as the backup area and the external device.
Communication means for performing communication between them. Soshi
At normal times, the data stored in the first storage means is used.
According to the configured control program and control data.
Controls certain control targets. In addition, external rewriting finger
Command, the data in the first storage means is stored in an external device.
The process of rewriting with new data sent from the device
Transfer the rewriting program to be executed into the second storage means.
And start it, and by executing this rewriting program,
1 The data in the storage means is transmitted from the external device to the new
Rewrite to the data. [0010] [0011] [0012] [0013]Especially here, Claims1Electronic control described in
The device displays a backup area in the second storage means.
Address information storage means for storing address information
If a rewrite command is received, the rewrite program
The address information stored in the address information storage means.
Of the storage area of the second storage means based on the
Transfer to a storage area other than the area and activate it.And update
In addition, the electronic control device according to claim 1 is a backup storage device.
It is provided with an area changing means and an address information updating means. So
And the backup area changing means includes the electronic control device.
When performing the normal control operation, the back-up of the second storage means is performed.
The second storage according to the amount of data to be stored in the up area
Change the backup area in the
The information updating means is a backup
Information in the address information storage
Update the stored address information. And such a claim1Described in
According to the slave control device, the rewriting program is stored in the second storage unit.
Transfer to a storage area other than the backup area in the
Can be sent, so backup of the second storage means
Do not lose valuable data stored in the area
The control program and control data in the first storage means.
Can be replaced.The electronic system according to claim 1.
The control device stores the data in the backup area of the second storage means.
Backup of the second storage means according to the amount of data to be
Change the area and change the backup area
The backup area in the second storage means is displayed accordingly.
Address information is updated. Therefore,
2 Even if the backup area of the storage
Program in a location other than the backup area of the second storage means.
Transfer to the storage area. Therefore, the claims
According to the electronic control device described in Item 1, the battery of the second storage means is
The backup according to the amount of data to be stored in the backup area
Backup area change operation and the backup area
The stored data is lost by rewriting program transfer
It is possible to surely achieve both prevention and prevention. [0015] The claimsIn oneThe electronic control unit described
Read-only, electrically rewritable data
The first storage means is a flash EEPROM (communication
Name, flash ROM or flash memory) or EE
A PROM is generally used, but another ROM may be used. Ma
A second memory device capable of reading and writing data.
As the stage, a normal volatile RAM is generally used.
Rush EEPROM or EEPROM may be used. Soshi
When a volatile RAM is used as the second storage means
Power supply backup part of the storage area with batteries etc.
By doing so, it is possible to provide a backup area
Flash EEPROM as the second storage means.
When using non-volatile memory such as M or EEPROM
Uses a part of the storage area as a backup area
What is necessary is just to set. On the other hand,In oneTo the electronic control unit described
The rewriting program is received from an external device
It may be transferred to the second storage means,
It is stored in advance in the first storage means, and from the first storage means
You may make it transfer to 2nd memory | storage means. And before
In the case of the
This is particularly advantageous in terms of memory capacity because no storage area is required.
is there. Even in the latter case, the data in the first storage means
Must be exchanged with external devices when rewriting
There is an advantage in that the number of unnecessary communication procedures is reduced. [0017] [0018] [0019] [0020] [0021] [0022] [0023] [0024] [0025] [0026] [0027] DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments to which the present invention is applied
Will be described with reference to the drawings. The embodiment of the present invention
Embodiments of the present invention are not limited to the following examples.
Can take various forms as long as it belongs to the technical scope of
Needless to say. [First Embodiment] First, FIG.
Engine control to control an internal combustion engine type engine mounted
Device (hereinafter referred to as ECU) 1 and built in ECU 1
When rewriting the engine control program or data
And a memory rewriting device 2 connected to the ECU 1.
All of the memory rewriting system 3 of the electronic control unit of the first embodiment.
It is a block diagram showing a body structure. As shown in FIG. 1, the ECU 1 includes an engine
Inputs signals from various sensors 4 that detect the operating state of the vehicle
Input processing circuit 6 for performing waveform processing by
Optimum control amount for the engine based on these sensor signals
CP that calculates and outputs a control signal based on the calculation result
U8 and the control signal from CPU8 receive engine
Attached injectors (fuel injection valves) and igniters
And an output circuit 12 for driving an actuator 10 such as
I have. Then, according to the program, the CPU 8
An operating microprocessor unit (hereinafter MP)
U) 18 and necessary for operating the MPU 18
Non-volatile ROM 20 for storing programs and data
And a RAM 22 for storing the operation result of the MPU 18 and the like,
While receiving signals from the input processing circuit 6 and the like,
An I / O 24 for outputting a control signal to the circuit 12,
For performing serial data communication with the switching device 2.
A communication circuit 25 is provided as communication means. Here, the ROM 20 and the RAM of the CPU 8
22 will be described. First, the ROM 20
Flash E that can erase and write data
EPROM (commonly called flash ROM or flash memory)
Memory), and the storage area of the ROM 20 is
A rewritable area 20a in which data can be rewritten;
Data rewriting is not possible (or data rewriting is prohibited)
Stopped) and a non-rewritable area 20b.
You. Then, the storage of the ROM 20 and the RAM 22
As shown in FIG. 2 showing the area, the rewritable area 20a
Stores control programs and control data for engine control.
Used as an area for storing constituent data
In the rewritable area 20a,
The data (ie control program and control data) is already
Is stored. The non-rewritable area 20b is
Data that constitutes the boot program executed immediately after setting
This is used as an area for storing data.
In the non-rewritable area 20b, the corresponding data (that is,
Boot program) has already been stored. Next, the storage area of the RAM 22 is shown in FIG.
In this way, the backup data can be retained even after the power supply is stopped.
Backup area 22a and the data is
Computing work area (that is, normal RAM area) that disappears 2
2b. And backup area 2
In 2a, the MPU 18 executed the control program
At the time of calculation and memorize it even after the power supply is stopped.
Learning value data and fail-safe data that must be used
Is stored, and in particular, as address information storage means.
The head area of the backup area 22a includes the backup
Information indicating the start address and the end address of the
Address (hereinafter referred to as start / end address information).
U) is stored. On the other hand, RAM
In the work area 22b, the operation result of the MPU 18 is temporarily stored.
Is stored in The calculation work area 22b or
Is the work area for calculation 22b and the backup area 22
a has a rewritable area of the ROM 20 as described later.
When rewriting the data stored in the area 20a,
ROM rewrite program transmitted from the rewriting device 2
Will be delivered. In this embodiment, the ROM 20
The replaceable area 20a corresponds to a first storage unit,
The RAM 22 corresponds to a second storage unit. Also, RA
M22 is a backup area 22a and an operation work area
(Normal RAM area) 22b
What can be set arbitrarily by the software is used. So
The RAM 22 has 8 bits per address.
(= 1 byte) is stored. On the other hand, as shown in FIG.
The memory rewriting device 2 of FIG.
Control programs and controls stored in the replaceable area 20a
In order to rewrite data, the CPU 8 on the ECU 1 side
CPU 14a for performing data communication and CPU 14a
The ROM 20 is controlled by the CPU
(High voltage required for rewriting (rewritable area 20a))
12V power supply circuit 1 for supplying voltage (12V in this embodiment)
4b and a command to rewrite the ROM 20 to the ECU 1
And a command switch SW for performing the operation. The ECU 1 and the memory rewriting device 2
The connection is made via the connection connector 26 to each other's communication line.
28, a power supply line 29, and a mode determination signal line.
The connection is performed by connecting each of the terminals 30. That is,
When the connection connector 26 is fitted, the connection
The CPU 14a of the memory rewriting device 2 and the ECU 1
Data communication with CPU 8
Memory rewriting via the power supply line 29.
From the 12V power supply circuit 14b on the device 2 side to the CP on the ECU 1 side
Voltage (12V) necessary for rewriting ROM 20 is written to U8
Supplied. Further, the mode determination signal line 30
Is pulled up to 5V by the resistor R on the ECU1 side
Command switch SW on the memory rewriting device 2 side.
Is connected to the ground potential (0 V) through
Therefore, the connection connector 26 is fitted and the command switch
When the switch is turned on, the ECU 1 determines a mode.
Signal line 30 from high level (5V) to low level
(0 V), and the CPU 8 determines the mode
If the fixed signal line 30 is at a low level, the ECU
1 is connected to the memory rewriting device 2 and
It is determined that a change command has been issued. The memory rewriting system configured as described above
3, in the ECU 1, as described above, the ROM 2
In the rewritable area 20a of 0, there is a control for engine control.
Control program and control data are stored.
The non-rewritable area 20b of the ROM 20 has
A boot program that is not an elephant is stored. Then, the CPU 8 of the ECU 1 controls the vehicle
When the ignition switch is turned on, the power
An operating voltage (5 V) is supplied from a circuit (not shown)
Operation from the reset state, and
The boot program stored in the non-replaceable area 20b
Start the system. And the memory rewriting device 2 is connected
Or the command switch SW is not turned on.
Normally, the ROM 20 is written by the boot program.
The control program stored in the replaceable area 20a is
Call and control the engine. The CPU 8 starts a boot program.
The memory rewriting device 2 is connected when the
When it is determined that the switch SW is turned on, the memory rewriting device
2 (CPU 14a) via the communication line 28.
ROM rewrite program transferred to RAM 22
And starts the ROM rewriting program on the RAM 22.
As a result, in the rewritable area 20a of the ROM 20,
Data stored in the memory rewriting device 2
New data (i.e., new control
And control data). On the other hand, the memory rewriting device 2 is connected to the ECU 1.
When a predetermined operation is performed by the operator after being continued,
According to the processing of FIG.
Any one of OM rewriting programs and engine control
Of new control programs and control data for
Data is sequentially transmitted. Then, next, the CPU 1 of the memory rewriting device 2
4a and the processing executed by the CPU 8 of the ECU 1.
The processing to be performed will be described with reference to FIGS.
FIG. 3 is executed by the CPU 14a of the memory rewriting device 2.
It is a flowchart showing the process performed. FIG.
Is a flowchart showing processing executed by the CPU 8 of the ECU 1.
Chart, and its steps (hereinafter simply referred to as “S”)
The processing from 100 to S150 is performed in the non-rewritable area 2
0b is executed by the boot program in S200
Is executed by the control program in the rewritable area 20a.
Performed by Then, the processing of S300 to S315
Is transmitted from the memory rewriting device 2 as described later.
The first ROM rewriting program transferred to the RAM 22
Therefore, the processing of S400 and S405 is
As will be described later, the RAM transmitted from the memory rewriting device 2
22 by the second ROM rewriting program transferred to
Be executed. First, in the memory rewriting device 2, an operator
When a certain operation is performed, the CPU 14a executes the processing shown in FIG.
Run. That is, in the first S10, as described later, EC
Upon receiving the RAM capacity information transmitted from U1,
Backup area 22a in RAM 22 of CU1
Storage area other than the above, that is, the capacity of the calculation work area 22b.
Check, and in S20, the RAM 22 on the ECU 1 side
The data stored in the backup area 22a
It is determined whether or not it is necessary to change the position. In this determination,
Calculation detected based on RAM capacity information from ECU 1
And the capacity of the work area 22b
The ROM rewriting program (especially
2 ROM rewriting program) and compare the capacity
The latter is larger and the work area
The second ROM rewrite program cannot be stored in the area 22b.
In this case, it is determined that data download is necessary. Then, in S20, the backup area 22
When it is determined that it is necessary to download the data in a
Proceeds to S30, and transfers the backup area 2 to the ECU 1.
Sends a siphoning request to send data in 2a
Then, in S40, the ECU responds to the siphoning request.
1 in the backup area 22a transmitted from
The data is received and stored in a predetermined storage medium. And this
In the case of (3), at S50, the ECU 1
First ROM for executing processing of 00 to S315
Send the rewrite program. On the other hand, in S20, data is downloaded.
If it is determined that is unnecessary, the process proceeds to S60, where the ECU
1 to execute the processing of S400 and S405 in FIG.
The second ROM rewriting program for the second is transmitted. And
After performing the processing of S50 or S60, the process proceeds to S70.
The rewritable area 20 of the ROM 20 is stored in the ECU 1
Stored in a in place of the old control program and control data
To send a new control program and control data to be
In the following S80, an affirmative determination is made in S20 and the ECU 1
Whether data in the backup area 22a has been downloaded
Is determined. Then, it is determined that data has been downloaded
If so, the process proceeds to S90, and a predetermined record is made in S40.
The data in the backup area 22a saved in the storage medium
The data is transmitted to the ECU 1 and then processed by the memory rewriting device.
End the process. In S80, data is downloaded.
If it is determined that it has not been
The processing on the switching device side ends. Therefore, the CPU 14a of the memory rewriting device 2
Executes the processing of FIG.
The communication time chart of FIG.
Such communication will be performed. That is, memory rewriting
The device 2 is transmitted from the ECU 1 as described later.
When the RAM capacity information is received (S10), the ECU 1
The data stored in the backup area 22a of the RAM 22
Only when it is necessary to siphon the data (S20: YE
S), a siphoning request is transmitted to the ECU 1 (S30).
And if you send a siphoning request,
Backup area 2 sent from ECU 1 in response
After receiving and storing the data in 2a (S40), the EC
The first ROM rewriting program is transmitted to U1 (S5).
0) Also, if no siphoning request is sent
(S20: NO), the RAM capacity information from the ECU 1 is received.
After the communication, the second ROM rewriting program
It is transmitted (S60). And further, the first and second ROs
After sending one of the M rewrite programs, the EC
Send new control program and control data to U1
(S70) After that, when a siphoning request signal is transmitted
(S80: YES), the ECU 1
The data from the side is transmitted to the ECU 1 (S90), and
The communication of is ended. Note that, in FIG.
The data is transmitted from the memory rewriting device 2 by transmitting a siphoning request.
And time indicated by t1 to t5
Is an idle time during transmission of each communication data. Next, the ECU 1 is turned on.
And the CPU 8 starts the operation from the reset state.
The processing shown in is performed. That is, first, the ROM 20
The boot program stored in the non-replaceable area 20b is
Upon activation, first in S100, the ROM rewrite mode is set.
It is determined whether or not the mode determination signal line 30 is at a low level.
It is determined based on whether there is any
It is determined that the mode is the normal mode other than the M rewrite mode, and
Proceed to 105. Then, in S105, the RAM 22
Storage area subsequent to the backup area 22a,
Clear the work area 22b and perform initial settings.
Jump to the engine control program. Then, RO
Control stored in rewritable area 20a of M20
The program is started, and thereafter, as shown in S200 of FIG.
In this way, the engine is executed with reference to the engine control data.
A gin control process is executed. The engine system of S200
The control process is performed based on various sensor signals from the input processing circuit 6 and the RO.
The control data stored in the rewritable area 20a of M20
The optimal fuel injection amount and point for the engine
Calculate the fire timing, etc., and use the injector according to the calculation result.
For driving the actuator 10 such as the
The control signal is output. Soshi
As a result, such an engine control process is executed.
Thus, the engine can be operated. On the other hand, in the boot program, the S
If it is determined at 100 that the mode is the ROM rewriting mode,
The process proceeds to S110 and stores the above RAM capacity information in the memory.
The data is transmitted to the rewriting device 2. This RAM capacity information is represented by R
For operations other than backup area 22a in AM22
This is information representing the capacity of the work area 22b.
Is the backup area 22 of the RAM 22 as described above.
Based on the start / end address information stored in a
Then, RAM capacity information is generated. Therefore, memory rewriting
The RAM 2 stores the RAM capacity information in S10 of FIG.
Receiving the information, the information is stored in the RAM 22 of the ECU 1.
Check the capacity of the work area 22b for calculation in
Can be. Note that the memory rewriting device 2 side
If the total capacity is known, the above
Send start / end address information as it is
Is also good. That is, in this case, the memory rewriting device 2 side
And backup area based on start / end address information
22a can be known, and the
The capacity of the work area 22b can also be known. Then, RAM capacity information is transmitted in S110.
Then, at S115, the memory rewriting is performed within a predetermined time.
Based on whether or not the siphoning request from device 2 has been received.
ROM rewriting program transmitted from the memory rewriting device 2
The program is outside the backup area 22a of the RAM 22
It is determined whether the data can be stored in the calculation work area 22b.
A process as a determining means is executed. And sucking
When the update request is received, the ROM rewrite program
Is not stored in the calculation work area 22b.
Then, the process proceeds to S120, where the backup area 2 of the RAM 22 is
2a is stored in the memory rewriting device 2
The data is transmitted to the memory rewriting device 2 to be stored in the memory rewriting device 2.
I do. Then, in subsequent S125, the memory rewriting device 2
Wait until the serial data is received,
Data is received, in this case, the data
Is the first ROM rewriting program transmitted in S50 of FIG.
Since the data constitutes the system, the process proceeds to S130,
The first ROM rewriting program from the memory rewriting device 2
Upon reception, the start address of the RAM 22 (that is, the backup area
(The first address of the area 22a). And continue
In S135, the process jumps to the start address of the RAM 22. Then, the processing in S125 and S130 is performed.
Therefore, the first data transferred from the memory rewriting device 2 to the RAM 22
1 ROM rewriting program is started, thereby
The processing of 00 to S315 is executed. The first ROM
The rewriting program executes the processing of S300 and S305
The rewritable area 20a of the ROM 20 for
S310 and S315 are executed.
The backup area 22a of the RAM 22 for
A rewriting program, as shown in FIG.
At least regarding the latter backup area 22a.
The rewrite program performs operations on areas other than the backup area 22a.
Is stored in the work area 22b. In other words, it will be described later
As described above, in the processing of S310 and S315, the backup
Executes processing to handle data in area 22a
The program to execute is other than the backup area 22a.
It is placed in. In this manner, the first ROM rewriting program
When the program is started, first in S300, the memory rewriting device
Wait until receiving serial data from
If it is determined that the data has been received, in this case,
The new control program transmitted in step S70 of FIG.
And S3 because it is data constituting control data.
05, a new control program from the memory rewriting device 2
Program and control data, and
The rewritable area 20a is erased and received in the erased area.
Write new control program and control data received
No. Then, in the following S310, the memory rewriting is performed again.
Wait until serial data is received from device 2
If it is determined that the full data has been received,
The data is the data transmitted in S90 of FIG.
Data stored in the backup area 22a
Therefore, the process proceeds to S315, where the data from the memory rewriting device 2 is read.
The data is received and the backup area 22a of the RAM 22 is received.
And thereafter, all the processing ends. On the other hand, in step S115, the memo is
When the siphoning request from the rewriting device 2 is not received
Contains a ROM rewriting program from the memory rewriting device 2.
Are used for operations other than the backup area 22a of the RAM 22.
It is determined that the data can be stored in the work area 22b, and S14
Move to 0. Then, in S140, the memory rewriting is performed.
Wait until serial data is received from device 2, and
If it is determined that real data has been received,
The data is rewritten in the second ROM rewrite transmitted in S60 of FIG.
Since the data constitutes the program, S145
To the second ROM rewriting program from the memory rewriting device 2.
Receive the program. And further, in this S145,
Stored in the backup area 22a of the RAM 22
Backup area 22 based on start / end address information
a the last address of the second ROM
The rewriting program is stored in the backup area 22 of the RAM 22.
after a (in other words, at the beginning of the operation work area 22b)
(From the address). Then, in the following S150,
Immediately after the last address of the backup area 22a of the RAM 22
Later (in other words, the start address of the work area for calculation 22b)
Jump to Then, the processing in S140 and S145 is performed.
Therefore, the first data transferred from the memory rewriting device 2 to the RAM 22
The ROM rewriting program of Step 2 is started, and thereby, S4
00 and S405 are executed. Note that the second RO
The M rewrite program is stored in the rewritable area 2 of the ROM 20.
FIG. 5 (B), which consists of only the rewriting program for 0a
As shown in FIG.
Is stored only in the work area 22b. In this manner, the second ROM rewriting program
When the program is started, first in S400, the memory rewriting device
And waits until serial data is received. Soshi
If it is determined that serial data has been received,
Is the new control whose data was transmitted in S70 of FIG.
Data that constitutes program and control data
Then, the process proceeds to S405, where a new
Control programs and control data, and
The rewritable area 20a of the OM 20 is erased and erased.
Control program and control data received in the area
Write. Then, after executing the processing of S405,
Ends the processing. As described above, the method of the first embodiment is described.
The mode is determined by the ECU 1 in the memory rewriting system 3.
Is determined to be at the low level (S
100: YES), the backup area 22 of the RAM 22
a based on the start / end address information stored in
The generated RAM capacity information is transmitted to the memory rewriting device 2, and
In response to this, the memory rewriting device 2 transmits a siphoning request.
Whether or not the ROM rewriting program
Work area 22 other than the backup area 22a
b to determine whether or not it can be stored.
(S110, S115). Then, the ROM rewriting program executes
When it is determined that the data cannot be stored in the work area 22b,
(S115: YES), backup area of RAM22
22a is stored in the memory rewriting device 2
To the memory rewriting device (S120).
2 and then the first from the memory rewriting device 2
Transfer the ROM rewrite program to all areas of the RAM 22
By activating (S125 to S135), the ROM
22 is replaced with new data from the memory rewriting device 2.
(S300, S305), and then
Stored in the backup area 22a of the RAM 22
Data is received from the memory rewriting device 2 and backed up
It returns to the area 22a (S310, S31
5). The ROM rewriting program is stored in the RAM 22
Is determined to be storable in the calculation work area 22b.
In this case (S115: NO), the backup area 22a
Without sending the data in the memory to the memory rewriting device 2.
The second ROM rewriting program from the memory rewriting device 2
The start / end addresses stored in the backup area 22a
Calculation work area 22 of RAM 22 based on dress information
b to be activated (S140 to S150).
Thus, the data in the ROM 22 is read from the memory rewriting device 2.
The data is rewritten with new data (S400,
S405). That is, in the ECU 1 of this embodiment, the ROM
The rewrite program is stored in the backup area 22 of the RAM 22.
It is determined whether the data can be stored in a storage area other than a, and
If it cannot be stored, the RAM 22 of the ROM rewriting program
To erase the data in the backup area 22a
Data in the backup area 22a.
Data to the memory rewriting device 2 and then rewrite the ROM
Transfer the program to an arbitrary area of the RAM 22 and start it
Conversely, if it can be stored, RO
The M rewrite program is stored in the backup area 22 of the RAM 22.
Transfer to only the storage area other than a and start it
I have. Therefore, according to the ECU 1 of this embodiment, R
Learning value stored in backup area 22a of AM 22
Data or fail-safe data is lost
Without rewriting the contents of ROM 20
You. In addition, the ECU 1 of this embodiment has a ROM rewriting program.
Transfer the data to the RAM 22 to save the backup area.
When the data in 22a is really lost
Rewrites the data in the backup area 22a to the memory
Backup because it is evacuated to storage 2 side
Sends / receives data in the area 22a to / from the memory rewriting device 2.
The operation of communicating can be minimized. [Second Embodiment] Next, the electronic control of the second embodiment will be described.
The memory rewriting system of the control device will be described. 2nd real
The memory rewriting system of the present embodiment corresponds to the first embodiment described above.
Then, the CPU 8 of the ECU 1 executes in S200 of FIG.
In the engine control process, the fail safe shown in FIG.
The only difference is that the process is repeated every predetermined time.
ing. Therefore, the following describes this fail-safe processing.
Will be described. As shown in FIG.
When the execution of the safe processing is started, first, in S500,
For sensor 4, actuator 10, engine itself, etc.
Error detection processing to detect whether an error has occurred
And then, in S505, determine whether there is an abnormality.
I do. If it is determined that there is no abnormality,
Also, the fail-safe processing is terminated, but there is an abnormality.
If it is determined, the process proceeds to S510. Then, in S510, the RAM 22
The end stored in the backup area 22a as described above.
Address information is read, and in S515, S50
0 of the error occurrence code indicating the type of error detected in the process of 0
Only the capacity (2 bytes in this embodiment) of the RAM 22
Backup area to extend the backup area 22a
Execute the process as the area change means, and in the expanded area
The above error occurrence code is stored. And further, the following S5
At 20, the contents of the data indicating the engine state at the time of abnormality detection
Only the amount (14 bytes in this embodiment) of the RAM 22
Backup area to extend the backup area 22a
Execute the process as the area change means, and in the expanded area
Store the above data. Then, in S525, the backup is performed.
Address information for updating the end address information of the area 22a
After executing the process as the
End the process. Note that the end ad performed in S525
Update of the address information is based on the end address read in S510.
The value stored in the processing of S515 and S520 is added to the value of the information.
Address increase equivalent to a total of 16 bytes of data (actual
In the embodiment, one byte of data is stored per address of the RAM 22.
Because it is stored, it becomes “16”. ) And add
Back up later value as new end address information
Stored in the first area of the area 22a.
It is. Therefore, for example, as shown in FIG.
22 from $ F0000 to $ F1000
When initially set as the backup area 22a
In the case where an abnormality is detected by S500 in FIG.
Is backed up by executing S510 to S525.
Area 22a is from $ F0000 to $ F1010
And the value of the end address information is also $ F
It will be updated from 1000 to $ F1010. Soshi
Then, if another abnormality is detected once more,
The backup area 22a starts at address $ F0000 and ends at $ F1
020 and end address information
Is also updated from $ F1010 to $ F1020.
Become. In addition, "@" is a character (0-9, A-
F) represents a hexadecimal number. That is, in the ECU 1 of the second embodiment, the RA
Of data to be stored in the backup area 22a of the M22.
The backup area 22a of the RAM 22 is changed according to the amount.
At the same time as the backup area 22a is changed.
Then, the end address information of the backup area 22a is updated.
I am trying to make it new. The ECU 1 according to the second embodiment has a
The command rewriting device 2 is connected and the command switch SW is turned on.
In other words, in the ROM rewrite mode in S100 of FIG.
When it is determined that the
Based on the new end address information, the process after S110 in FIG.
The backup of the RAM 22.
Even if the storage area 22a is changed, the ROM rewriting program
Storage area of RAM 22 other than backup area 22a
(Ie, whether or not it can be stored in the calculation work area 22b)
The ROM rewriting program
When the data can be stored in the work area 22b, the ROM
The rewrite program is stored in the work area 22b for operation of the RAM 22.
Can be reliably transferred. Therefore, according to the ECU 1 of the second embodiment,
According to the amount of data to be stored in the backup area 22a
Operation for changing the backup area 22a
The data stored in the area 22a is stored in a ROM rewriting program.
To ensure that they are not lost due to
Can stand up. [Others] (1) In the ECU 1 of the first and second embodiments,
S100 to S1 of FIG.
Of the 50 processes, S110, S115, S140 to S1
50 is deleted, and if a positive determination is made in S110, S1
The processing after 20 may be executed. In addition, this
In this case, the CPU 14a of the memory rewriting device 2
Only the processes of S40, S50, S70, and S90 are sequentially executed.
Run. That is, by doing so, the ECU 1
Command switch SW is turned on when memory rewriting device 2 is connected
Then, the ROM rewrite program is
Regardless of whether it can be stored in the work area 22b,
The data currently stored in the up area 22a is
The data is transmitted to the rewriting device 2 and is temporarily stored. So
Then, even in this case, the backup area of the RAM 22 is
Learning value data and the like stored in the area 22a are lost
Without rewriting the contents of ROM 20
You. (2) The ECU 1 of the first and second embodiments
In the ROM rewriting program (particularly the second ROM
Conversion program) is a work area 22b for operation in the RAM 22.
If it is determined that it can be stored in
S15 to S15 of FIG.
0, S110 to S135 are deleted and S11
If the determination is affirmative, the processing after S140 is executed.
You may make it so. In this case, the memory rewriting device
The second CPU 14a performs the processing of S60 and S70 of FIG.
Are sequentially executed. That is, even in this case, the ECU 1
Command switch SW is turned on when memory rewriting device 2 is connected
The ROM rewriting program from the memory rewriting device 2
Program (second ROM rewriting program) in RAM 22
The data can be reliably transferred to the arithmetic work area 22b.
Learning data in the backup area 22a is lost
Can be prevented. (3) As in the ECU 1 of the first embodiment, R
Backup area 22a and work area for operation of AM22
If the capacity of the area 22b does not change, the backup area
The start / end address information of the area 22a is written in the ROM 20.
In the non-rewritable area 20b or in the ROM 20
The control program and control data are stored in the exchangeable area 20a.
It may be stored together with the data. (4) For the ECU 1 of the first embodiment,
In the case of adopting the mode (2), a memo as an external device is used.
From the rewriting device 2 to the ECU 1, a backup area 22a
May send start / end address information
No. (5) In each of the above embodiments, the backup area 22a
Start / end address information (especially end address information)
Instead, the start address information of the work area for calculation 22b
May be used. (6) In the ECU 1 of each of the above embodiments, the RO
Receiving the M rewriting program from the memory rewriting device 2
Transfer to M22, but rewrite ROM20
The ROM rewrite program is stored in the
The ROM rewrite program from the ROM 20 to R
The same applies to the case of a configuration for transferring data to the AM 22. For example, in the case of the first and second embodiments,
Explaining this, the ECU 1 determines that S110 and S11 in FIG.
5 starts and ends the backup area 22a.
Work area in the RAM 22 based on the
22b, and the determined capacity and the second RO
Compare the capacity of the M rewrite program to the second ROM
The replacement program is stored in the operation work area 22b of the RAM 22.
What is necessary is just to determine whether or not storage is possible. And S1
25, S130 or S140, S145,
From the non-rewritable area 20b of the ROM 20, the first and
Read out the corresponding one of the ROM rewriting programs
Then, it may be stored in the RAM 22. In addition, this
In this case, the memory rewriting device 2
When data in the up area 22a is transmitted
Executes the processes of S40, S70, and S90 in FIG.
Otherwise, only the process of S70 in FIG.
No. And, such a configuration, as in the second embodiment,
Backup area 22a of RAM 22 and work for calculation
This is particularly effective when the capacitance of the region 22b changes.
is there. (7) In each of the above embodiments, the engine is controlled.
Although the description has been given of the ECU 1 that
Is not limited to this. That is, for example,
Control objects to be controlled, such as missions and suspensions
The same applies to electronic control units.
Wear.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram illustrating an overall configuration of a memory rewriting system of an electronic control unit according to a first embodiment. FIG. 2 is an explanatory diagram illustrating storage areas of a ROM and a RAM. FIG. 3 is a flowchart illustrating a process executed on the memory rewriting device side. FIG. 4 is a flowchart showing processing executed on an engine control device (ECU) side. FIG. 5 is an explanatory diagram illustrating a storage state of a ROM rewriting program in a RAM. FIG. 6 is a time chart illustrating communication performed between the memory rewriting device and the ECU. FIG. 7 is a flowchart illustrating a fail-safe process executed during engine control on the ECU side according to the second embodiment. FIG. 8 is an explanatory diagram illustrating an execution state of the processing in FIG. 7; [Description of Signs] 1 ... Engine control device (ECU) 2 ... Memory rewriting device SW ... Command switch 3 ... Memory rewriting system 4
... Sensor 6 ... Input processing circuit 8 ... CPU 10 ... Actuator 12 ... Output circuit 18 ... Microprocessor unit (MPU) 20 ... ROM 20a ... Writable area 20b
... non-rewritable area 22 ... RAM 22a ... backup area 22b
... Calculation work area 24. I / O 25. Communication circuit 26. Connector 28. Communication line 30. Mode determination signal line.

Claims (1)

(57) [Claim 1] A read-only first storage means capable of electrically rewriting data, and a power supply capable of reading and writing data and a part of a storage area being provided with a power supply. A second storage unit that is set as a backup area for continuously holding data even after the supply is stopped; and a communication unit that communicates with an external device. A predetermined control target is controlled in accordance with a control program and control data constituted by data stored in the means, and when an external rewrite command is received, data in the first storage means is transmitted from the external device. By transferring a rewriting program for executing a process of rewriting to new data that has been transferred into the second storage means and starting the rewriting program, the data in the first storage means is transferred. An electronic control unit for rewriting to new data transmitted from the external device, wherein the backup area in the second storage unit is displayed.
Address information storage means for storing address information
In addition, when receiving the rewriting instruction,
Conversion program stored in the address information storage means.
Storing the second storage means based on the address information
Transfer to storage area other than the backup area
And when the electronic control unit performs a normal control operation,
Of data to be stored in the backup area of the second storage means
The backup in the second storage means, depending on the volume.
Backup area changing means for changing a backup area, and the backup area by the backup area changing means.
The address information is stored in the address information storage means according to the change of the area.
Address information updating means for updating the address information obtained
Electronic control equipment, characterized in that it comprises a and.