JP2004287712A - Electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic device having a plurality of storage devices provided with a rewriting program capable of being shared by various electronic devices. <P>SOLUTION: A main rewriting program has a read-in program for reading a sub-rewriting program for rewriting memory content of an EEPROM 5 and rewriting EEPROM data from a program rewriting device 11. The sub-rewriting program is executed, whereby the rewriting EEPROM data are written in the EEPROM 5. Accordingly, the need for changing the main rewriting program according to the structure of a storage device the storage content of which is to be rewritten by the sub-rewriting program is eliminated to enable the sharing by each electronic device. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electronic device equipped with a plurality of storage devices capable of rewriting a program or data stored in each storage device to a program or data obtained from outside.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, an electronic device that stores an operation program in a nonvolatile memory such as a flash memory and operates according to the operation program is known. This conventional device has a configuration in which an operation program stored in the above-described nonvolatile memory can be rewritten using an external device prepared separately for upgrading the operation program. Specifically, an operation program for rewriting is acquired from an external device by rewriting software stored in advance in a nonvolatile memory, and is stored in the nonvolatile memory.
[0003]
[Problems to be solved by the invention]
In recent years, electronic devices having a plurality of storage devices have been put to practical use. In such an electronic device, usually, a rewrite operation program and rewrite data unique to each storage device for rewriting a program and data stored in each storage device are stored in a main storage device. By executing the rewriting program, the program can be downloaded from an external device.
[0004]
However, some electronic devices do not have a secondary storage device, and some of the secondary storage devices do not allow rewriting. For this reason, it is necessary to prepare a rewriting program corresponding to the configuration of the storage device mounted on each electronic device and properly use the rewriting program stored in the main storage device so as to be adapted to each electronic device. .
[0005]
The present invention has been made in view of the above problems, and has as its object to provide an electronic device having a plurality of storage devices, including a rewriting program that can be used in common for various electronic devices.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the electronic device according to claim 1 is an electronic device that operates according to an operation program, wherein the electronic device stores at least a main storage device that stores an operation program and various data. A sub-storage device, wherein the storage contents stored in the main storage device can be rewritten by the electronic device executing a main rewriting program, and the storage contents stored in the sub-storage device Is configured to be rewritable by the electronic device executing the sub-rewriting program. The main rewriting program is stored in the main storage device, and is rewritten in the sub-rewriting program and the sub storage device together with the operation program to be rewritten. And the rewrite data to be acquired from the external device and written to the main storage device. Inclusive, sub rewriting program is executed in conjunction with during execution of the operation program, and writes the data for rewriting acquired from an external device to the sub-storage apparatus.
[0007]
Thus, in the electronic device according to the first aspect, the main rewriting program acquires the sub rewriting program and the rewriting data together with the operation program to be rewritten from the external device and writes the sub rewriting program and the rewriting data in the main storage device. The sub-rewriting program is executed simultaneously with the execution of the operation program, and writes the rewriting data obtained from the external device into the sub-storage device. Thereby, the sub rewrite program and the rewrite data are acquired from the external device by the main rewrite program and written to the main storage device, so that the main rewrite program according to the configuration of the sub storage device does not need to be changed, It can be used in common for each electronic device.
[0008]
According to the present invention, a rewriting necessity flag is provided to indicate whether rewriting of the storage contents of the sub storage device is required, and the rewriting necessity flag is set when the main rewriting program rewrites the storage contents of the main storage device. It is preferable that the sub rewrite program rewrites the storage content of the sub storage device based on the rewrite data when the rewrite necessity flag is set. Thus, for example, even when the power of the electronic device is turned off while the storage content of the sub storage device is being rewritten, the rewriting necessity flag is referred to when the power is turned on again. Since the storage contents of the sub storage device can be rewritten again, the storage contents of the sub storage device can be reliably rewritten.
[0009]
Preferably, the rewriting necessity flag is reset when the change of the storage content of the sub storage device is prohibited. Thus, if the sub storage device is a read-only storage device such as a mask ROM, the rewriting necessity flag is reset, so that it is not necessary to change the sub rewriting program according to the configuration of the sub storage device. It can be used in common for each electronic device.
[0010]
As described in claim 4, it is desirable that the rewriting necessity flag be stored in the sub storage device. This makes it possible to reliably store the contents of the rewrite necessity flag even when the power is shut off during the operation of the electronic device.
[0011]
As described in claim 5, the sub storage device is provided with a storage area for each type of data to be stored, and the main rewrite program rewrites the storage content of the main storage device with respect to the sub rewrite program. It is desirable to provide an initialization routine for initializing the storage contents of a specific storage area of the sub storage device.
[0012]
When the storage content of the main storage device is rewritten, it may be necessary to initialize the storage content of a specific storage area of the sub storage device accordingly. Therefore, an initialization routine for initializing the storage content of a specific storage area in the sub storage device is provided for the sub rewrite program, and when the main rewrite program rewrites the storage content of the main storage device, By executing the above-described initialization routine to initialize the storage contents of the specific storage area in the sub storage device, the specific storage of the sub storage device can be performed without adding a function for initialization to an external device. It is possible to automatically initialize the storage contents of the area.
[0013]
The main rewriting program stores the rewriting data in a specific storage area provided in the main storage device, and the sub rewriting program stores the rewriting data in the specific storage area. It is preferable to select a storage area to be rewritten by the rewriting data from the storage areas of the sub-storage device provided for each type of data to be stored, based on the address of the storage area. Thus, it is only necessary to store only the rewrite data in a specific storage area provided in the main storage device, and it is not necessary to provide information on the designation of the storage area of the sub storage device. It becomes possible to use it efficiently.
[0014]
According to a seventh aspect of the present invention, the main rewriting program acquires an identification code indicating a type of the rewriting data when acquiring the rewriting data from the external device. It is desirable to rewrite the storage content of the data storage area of the sub storage device of the type corresponding to the code with the rewriting data. As a result, the sub rewrite program can selectively rewrite only the storage content of an arbitrary storage area from the data storage area provided in the sub storage device.
[0015]
It is preferable that the identification code is a transmission command when the external device transmits the rewriting data to the electronic device. Thus, the communication command used when the external device outputs the rewriting data to the electronic device can be used as it is as the identification code.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
FIG. 1 is a block diagram showing the overall configuration of the electronic device according to the first embodiment of the present invention. The electronic device according to the present embodiment is applied to an electronic control device 1 for a vehicle engine.
[0017]
The input circuit 2 is, for example, an A / D converter, and acquires sensor information from various sensors 3 that detect the engine speed, cooling water temperature, and the like (not shown). In addition, switching information from various switches 4 related to engine control such as an ignition switch (not shown) is obtained. The acquired sensor information and switching information are output to the microcomputer 6.
[0018]
The EEPROM 5 serving as a sub-storage device is a nonvolatile storage element whose storage content can be electrically rewritten, and is connected to the microcomputer 6 by a communication line. The storage area of the EEPROM 5 includes three storage areas: a failure data area 51, a vehicle code area 52, and a rewrite necessity code area 53 (see FIG. 2A). The failure data area 51 stores data relating to a failure that occurred during the operation of an engine (not shown), and the vehicle code area 52 stores data relating to the vehicle code of the vehicle.
[0019]
The rewriting necessity code area 53 indicates whether or not the data relating to the failure stored in the failure data area 51 and the data relating to the vehicle code stored in the vehicle code area 52 need to be rewritten. A reject flag is stored. The state in which the rewrite necessity flag is set indicates that the storage content of the EEPROM 5 needs to be rewritten, and the state in which the rewrite necessity flag is reset indicates that rewrite is unnecessary. .
[0020]
The microcomputer 6 includes a flash memory 7, a CPU 8, and a RAM 9.
[0021]
The flash memory 7, which is a main storage device, is a nonvolatile storage element whose storage contents can be electrically rewritten, and includes a normal mode program area 71, a rewrite mode program area 72, and an EEPROM data area 73. (See FIG. 2B).
[0022]
In the normal mode program area 71, a control program (operation program) for controlling the engine and a sub rewrite program for rewriting the storage contents stored in the EEPROM 5 are stored. The sub-rewriting program according to the present embodiment has an initialization routine for initializing the storage contents of the failure data area 51 of the EEPROM 5.
[0023]
On the other hand, a main rewrite program for rewriting the storage contents of the normal mode program area 71 is stored in the rewrite mode program area 72. The main rewrite program includes a control program written in the normal mode program area 71 and a communication circuit. And a reading program to be read from the program rewriting device 11 via the control unit 10. The reading program reads, from the program rewriting device 11 via the communication circuit 10, a sub rewriting program and EEPROM data for rewriting which is rewritten by the sub rewriting program, in addition to the control program. Note that with respect to the rewrite mode program area 72, a specific storage area of the flash memory 7 is preset as the rewrite mode program area 72, and only the reading of the storage contents of the storage area is permitted, and the writing is not performed. prohibited.
[0024]
The EEPROM data area 73 stores EEPROM data for rewriting for rewriting data stored in the EEPROM 5.
[0025]
The CPU 8 has two operation modes, a normal mode and a rewrite mode.
[0026]
When the operation mode is the normal mode, the CPU 8 executes the control program stored in the normal mode program area 71 of the flash memory 7 based on various sensor information and various switching information obtained from the input circuit 2, Calculations required for engine control are performed, and the calculation results are stored in the RAM 9. Then, based on the calculation results stored in the RAM 9, an injection control signal and an ignition control signal for controlling the injector 12 and the igniter 13 are generated and output to the output circuit 14.
[0027]
The CPU 8 constantly monitors the operating state of an engine (not shown) based on various sensor information and various switching information obtained from the input circuit 2. If a failure occurs, the CPU 8 operates the failure data area 51 of the EEPROM 5. Write the data on the fault that has occurred.
[0028]
On the other hand, when the operation mode is the rewrite mode, the CPU 8 executes the main rewrite program stored in the rewrite mode program area 72 of the flash memory 7 and controls the program rewrite device 11 via the communication circuit 10. A program, a sub-rewriting program, and EEPROM data for rewriting are obtained. Then, the obtained control program, sub-rewrite program, and rewritten EEPROM data are written in the flash memory 7. At this time, the control program and the sub rewrite program are written in the normal mode program area 71, and the EEPROM data for rewriting is written in the EEPROM data area 73.
[0029]
In particular, when writing the control program, the sub-rewriting program, and the EEPROM data for rewriting to the flash memory 7, the main rewriting program according to the present embodiment includes the rewriting necessity stored in the rewriting necessity code area 53 of the EEPROM 5. Set the flag. The rewriting necessity flag is reset when the rewriting of the stored contents of the EEPROM 5 is completed.
[0030]
Note that the rewriting mode is executed only when the electronic control unit 1 is activated and the entry conditions for the rewriting mode are satisfied. The entry condition described above is a condition that a rewrite request signal is output from the program rewriting device 11, an engine (not shown) is stopped, and a battery voltage (not shown) is 10 V or more.
[0031]
A program rewriting device 11 which is an external device outputs a control program, a sub rewriting program, and EEPROM data for rewriting to the communication circuit 10. At that time, a rewrite request signal is output to the electronic control unit 1.
[0032]
The output circuit 14 acquires the injection control signal and the ignition control signal output from the microcomputer 6 and outputs these to the injector 12 and the igniter 13, respectively.
[0033]
FIG. 3 is a flowchart illustrating a process in which the electronic device of the present embodiment determines an operation mode at the time of startup. The process of this flowchart is executed every time the electronic device is started.
[0034]
In step 301, the microcomputer 6 determines whether or not the entry condition of the rewrite mode is satisfied. If the entry condition is satisfied, the process proceeds to step 302. If the entry condition is not satisfied, the process proceeds to step 304.
[0035]
In step 302, an initialization routine provided in the sub rewrite program is executed to initialize the storage contents of the failure data area 51 of the EEPROM 5. By initializing the storage contents of the failure data area 51 of the EEPROM 5 by the initialization routine, the initialization can be automatically performed without adding a function for initialization to the program rewriting device 11. is there.
[0036]
In step 303, a rewriting necessity flag in the rewriting necessity code area 53 of the EEPROM 5 is set. By storing the rewriting necessity flag in the EEPROM 5, the data in the EEPROM 5 can be rewritten in the normal mode after the control program, the sub rewriting program, and the rewriting EEPROM data in the flash memory 7 are rewritten.
[0037]
In step 304, a rewrite mode process is executed. In step 305, normal mode processing is executed.
[0038]
If a read-only storage element such as a mask ROM is used instead of the EEPROM 5, the rewrite necessity flag is reset in step 303. As a result, the sub rewrite program can be used in common for each electronic device.
[0039]
FIG. 4 is a flowchart relating to processing executed in the rewrite mode by the electronic device of the present embodiment. The process of this flowchart corresponds to the rewrite mode process of step 303 in the flowchart of FIG.
[0040]
In step 401, the microcomputer 6 executes the reading program of the main rewriting program to acquire the control program, the sub rewriting program, and the EEPROM data for rewriting from the program rewriting device 11.
[0041]
In step 402, the control program, sub-rewrite program, and EEPROM data for rewriting acquired in step 401 are written in the flash memory 7.
[0042]
FIG. 5 is a flowchart relating to processing executed by the electronic device of the present embodiment in the normal mode. The processing of this flowchart corresponds to the normal mode processing of step 304 in the flowchart of FIG.
[0043]
In step 501, it is determined whether or not the rewriting necessity flag in the rewriting necessity code area 53 of the EEPROM 5 is set. Thus, for example, even when the power of the electronic control unit 1 is cut off while the storage contents of the EEPROM 5 are being rewritten, the storage of the EEPROM 5 is referred to by referring to the rewriting necessity flag when the power is turned on again. The contents can be rewritten again, and the contents stored in the EEPROM 5 can be surely rewritten. If the rewrite necessity flag is set, the process proceeds to step 502. Otherwise, go to step 504.
[0044]
In step 502, the sub-rewriting program is executed to write the rewriting EEPROM data stored in the EEPROM data area 73 of the flash memory 7 into the EEPROM 5. At that time, the EEPROM data for rewriting is written to the storage area of the EEPROM 5 corresponding to the address of the EEPROM data area 73. Thus, only the EEPROM data for rewriting need only be stored in the EEPROM data area 73, and data relating to the designation of the storage area in the EEPROM data area 73 becomes unnecessary. Therefore, it is possible to keep the EEPROM data area 73 small. It becomes possible.
[0045]
In step 503, the rewriting necessity flag in the rewriting necessity code area 53 of the EEPROM 5 is reset. In step 504, the control program is executed to start the engine control.
[0046]
As described above, the electronic device of the present embodiment is provided with the sub-rewriting program for rewriting the storage content of the EEPROM 5 and the reading program for reading the rewriting EEPROM data from the program rewriting device 11 for the main rewriting program. Then, by executing the read sub-rewriting program, the EEPROM data for rewriting is written to the sub-storage device. Thus, there is no need to change the main rewriting program according to the configuration of the storage device whose storage content is to be rewritten by the sub rewriting program, and the main rewriting program can be used in common for each electronic device.
[0047]
(2nd Embodiment)
Next, an electronic device according to a second embodiment of the present invention will be described. The electronic device of the present embodiment is different from the first embodiment in that the storage contents of the EEPROM 5 can be selectively rewritten for each storage area.
[0048]
The program rewriting device 11 of the present embodiment transmits the rewriting data of each storage area provided in the EEPROM 5 to the electronic control device 1 as rewriting EEPROM data together with an ID code (identification code) indicating the storage area. In this case, the transmission is performed according to the data format shown in FIG.
[0049]
In the ID code part of FIG. 6, an ID code indicating which storage area in the EEPROM 5 the rewriting data transmitted by the program rewriting device 11 is for rewriting data is set. In the present embodiment, two types of ID codes, ie, ID codes indicating failure data and ID codes indicating vehicle codes, are prepared. In the data number part, the total number of divisions when the rewrite data is divided for each predetermined data amount is set. In the data portion, each divided data obtained by dividing the data for rewriting into the above-described total number of divisions is set. This data portion is provided by the total number of divisions described above.
[0050]
The main rewriting program according to the present embodiment extracts an ID code, the number of data, and each divided data from the rewriting EEPROM data transmitted from the program rewriting device 11 in accordance with the data format of FIG.
[0051]
When rewriting the storage contents of the EEPROM 5, the sub-rewriting program of the present embodiment reads the ID code stored in the EEPROM data area 73, and stores the corresponding storage contents of the storage area of the EEPROM 5 in the EEPROM 5. Rewriting is performed with the rewriting data stored in the data area 73.
[0052]
Other configurations and operations are the same as those in the first embodiment, and thus will not be described.
[0053]
FIG. 7 is a flowchart relating to a process executed by the electronic device of the present embodiment in the normal mode. As shown in FIG. 7, the flowchart of this embodiment is different from the flowchart of FIG. 5 of the first embodiment in that the step of writing the data stored in the EEPROM data area 73 into the EEPROM 5 is replaced with the step of writing the EEPROM data area. A step of writing rewriting data to a storage area corresponding to the ID code stored in 73 is provided. In other words, all the processes other than step 802 are the same as the processes in the flowchart of FIG.
[0054]
In step 805, the microcomputer 6 transfers the rewriting data stored in the EEPROM data area 73 of the flash memory 7 to the storage area of the EEPROM 5 corresponding to the ID code similarly stored in the EEPROM data area 73 of the flash memory 7. Write.
[0055]
As described above, in the electronic device of the present embodiment, it is possible to selectively rewrite the storage content of each storage area provided in the EEPROM 5 by using the ID code indicating each storage area provided in the EEPROM 5. Become.
[0056]
In the present embodiment, the storage area of the EEPROM 5 to be rewritten is determined by the ID code. However, the program rewriting device 11 is provided with a communication command for rewriting the storage content of the EEPROM 5 for each storage area. , The transmission and the writing of the rewriting data may be executed. In this case, the ID code part in the data format of FIG. 6 is unnecessary.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an overall configuration of an electronic device according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a storage area configuration of an EEPROM and a flash memory.
FIG. 3 is a flowchart illustrating a process in which the electronic apparatus according to the first embodiment determines an operation mode at startup.
FIG. 4 is a flowchart relating to a process executed by the electronic device of the first embodiment in a rewrite mode.
FIG. 5 is a flowchart relating to a process executed by the electronic device of the first embodiment in a normal mode.
FIG. 6 is a diagram showing a data format when the program rewriting device of the second embodiment transmits rewriting data.
FIG. 7 is a flowchart relating to a process executed by the electronic device of the second embodiment in a normal mode.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Electronic control device, 2 ... Input circuit, 3 ... Various sensors, 4 ... Various switches, 5 ... EEPROM, 6 ... Program rewriting device, 7 ... Communication circuit, 8 ... Microcomputer, 9 ... Flash memory, 10 ... CPU, 11 ... RAM, 12 ... Injector, 13 ... Igniter

Claims (8)

An electronic device that operates according to an operation program, the electronic device includes at least a main storage device that stores an operation program and a sub storage device that stores various data, and a storage device that is stored in the main storage device. The contents can be rewritten by the electronic device executing the main rewriting program, and the storage contents stored in the sub storage device can be rewritten by the electronic device executing the sub rewriting program. It has a possible configuration,
The main rewrite program is stored in the main storage device, together with the operation program to be rewritten, the sub rewrite program and rewrite data to be rewritten in the sub storage device are obtained from an external device, and written to the main storage device.
The electronic device, wherein the sub rewriting program is executed together with the execution of the operation program, and writes rewriting data acquired from the external device to the sub storage device. A rewriting necessity flag indicating whether rewriting of storage contents of the sub-storage device is necessary is provided,
The rewriting necessity flag is set when the main rewriting program rewrites the storage content of the main storage device,
2. The electronic device according to claim 1, wherein the sub rewriting program rewrites the storage content of the sub storage device based on the rewriting data when the rewriting necessity flag is set. 3. The electronic device according to claim 2, wherein the rewriting necessity flag is reset when a change in storage content of the sub storage device is prohibited. The electronic device according to claim 2, wherein the rewriting necessity flag is stored in the sub storage device. The sub-storage device is provided with a storage area for each type of data to be stored,
An initialization routine for initializing the storage content of a specific storage area of the sub storage device when the main rewrite program rewrites the storage content of the main storage device with respect to the sub rewrite program is provided. The electronic device according to claim 2, wherein The main rewriting program is for storing the rewriting data in a specific storage area provided in the main storage device,
The sub-rewriting program is configured to execute, based on an address of the specific storage area where the rewriting data is stored, a storage area of the sub-storage device provided for each type of data to be stored, by using the rewriting data. The electronic device according to claim 5, wherein a storage area to be rewritten is selected. The main rewriting program is for acquiring an identification code indicating a type of the rewriting data when acquiring the rewriting data from the external device,
6. The electronic device according to claim 5, wherein the sub rewriting program rewrites a storage content of a data storage area of the type of the sub storage device corresponding to the identification code to the rewriting data. 8. The electronic device according to claim 7, wherein the identification code is a transmission command used when the external device transmits the rewriting data to the electronic device.

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