JP4517607B2 - Electronic device and method for updating the program - Google Patents

Description

  The present invention relates to an electronic device that operates based on a program stored in an internal memory, and a program update method for updating a program of such an electronic device.

  Various electronic devices such as household appliances, office equipment, and cellular phones in recent years are provided with control circuits such as a CPU (Central Processing Unit) and are stored in ROM (Read Only Memory). Operates based on program code.

  In such an electronic device with a built-in CPU, the system startup process after the power is turned on executes a boot loader composed of a relatively small group of executable codes, and then the boot loader executes the operation system program of the system. In general, it is a step-by-step activation operation such as reading an initial code.

  In recent years, as with application programs such as computers, even in electronic devices with a built-in CPU, the program code can be updated after completion of the device or after shipment to expand or correct the function of the device. .

  By the way, in the case of an electronic device capable of updating the program code, in the memory where the program code is stored, in addition to the program file existing at the time of shipment from the factory, the program file for the number of times of updating is stored. ing. For this reason, a boot loader applied to such an electronic device must perform a search process of searching for the latest version of a program file from among a plurality of program files.

However, if such a search process is executed at the time of startup, the startup process becomes complicated accordingly, and the execution code of the boot loader becomes longer.
Japanese Patent Application No. 2000-357095 JP 2002-358207 A

  The problem to be solved by the present invention is that the startup process becomes complicated and the execution code of the boot loader becomes large in an electronic device capable of updating the embedded program.

  Therefore, the present invention can perform a simple startup process in an electronic device capable of updating an embedded program without being aware of the version of the initial program executed at startup, and can further shorten the execution code of the boot loader. An object of the present invention is to provide an electronic device and a program update method thereof.

An electronic apparatus according to the present invention includes a working memory in which a program code is expanded, a first initial program file to which a first file name including a file title and an extension indicating the type of the file is assigned, a first indicates than the initial program file, a new initial program file version, the first file name and the second file name only a different extension is applied, version than the first initial program files A program memory in which a new second initial program file is stored in an updateable state from the outside, and the second initial program file when the second initial program file is stored in the program memory In the working memory and the second initial program file. If there are not stored in the program memory, the file name given to the first initial program file, the second file name by changing only the extension from the first file name Then, after the first initial program file after the change of the file name is expanded in the working memory, a boot loader for executing a startup process for starting the expanded program is stored in a predetermined physical quantity area. Boot memory, a process for reading the boot loader from the boot memory when the system is started, and the program code is expanded when the second initial program file is stored in the program memory. expand the working memory that, the second of the initial program files After There was changed to the second file name from the first file name by changing only the extension of the file name assigned to the first initial program file if not stored in the program memory in, after the first initial program after the change of the file name was developed in the working memory, and start processing you start the initial program extracted files, when updating the non-volatile memory update program is stored After the update program is read out, a third file name is given to the third initial program file which is the latest version inputted from the outside , and then the third file name is given. Are stored in the program memory, and the first initial program file is stored. When the second initial program file is stored in the program memory when the file is stored in the program memory, the first initial program file is deleted, and then the second initial program file is deleted. The file name assigned to the initial program file is changed from the second file name to the first file name, and the file name assigned to the third initial program file is changed from the third file name to the second file name. And when the first initial program file is stored in the program memory and the second initial program file is not stored in the program memory, A second file name is changed from the third file name assigned to the third initial program file to the second file name. And when the second initial program file is stored in the program memory when the first initial program file is not stored in the program memory, the second initial program file From the second file name to the first file name, and from the third file name to the second file name. And when the second initial program file is not stored in the program memory when the first initial program file is not stored in the program memory and the second initial program file is not stored in the program memory. The file name assigned to the initial program file 3 is changed from the third file name to the second file. Characterized in that it comprises a CPU for executing the update process and a fourth process of changing the name.

  When updating the initial program read by the boot loader for the electronic device of the present invention, a new initial program file is stored in the program memory and its name indicates that it is the latest version of the initial program file. A file having a name indicating that it is the latest version of the initial program file originally stored in the program memory is deleted or renamed.

  Then, the boot loader of the electronic device according to the present invention performs a process of selecting a file having a name indicating that it is the latest version of the initial program file from the program memory and expanding it to the working memory.

The program update method according to the present invention is a program update method for upgrading a program incorporated in an electronic device, wherein a first file name including a file title and an extension indicating a type of the file is assigned. an initial program file, that than the first initial program file, a new initial program file version shows, the first file name and the second file name only a different extension is applied, the first When the second initial program file is stored in a program memory in which a second initial program file whose version is newer than the initial program file is stored in an updateable state from the outside, the second initial program file is stored. Extract the initial program file to the above working memory and If the second initial program file is not stored in the program memory, the above-mentioned file name given to the first initial program file by changing only the extension from the first file name 2 After the file name is changed, the first initial program file after the change of the file name is expanded in the working memory, and then a boot loader for executing a startup process for starting the expanded program has a predetermined physical quantity area. A boot loader read step for executing a process for the CPU of the electronic device to read the boot loader from the boot memory stored in the system at the time of system startup, and the second initial program file when the second initial program file is stored in the program memory. Program code expands the initial program file of 2 By expanded in the working memory, the second initial program files to change only the extension of the file name assigned to the first initial program file if not stored in the program memory, the first after changing to the second file name from the first file name, after the first initial program file after the change of the file name was developed in the working memory, start you start the initial program extracted files A startup process execution step in which the CPU of the electronic device executes the process, and an update program is read from the non-volatile memory in which the update program is stored at the time of update, and then the third version which is the latest version input from the outside. A third file name was assigned to the initial program file Later, when the third initial program file assigned with the third file name is stored in the program memory, and the first initial program file is stored in the program memory, the second initial program file is stored. Is stored in the program memory, the first initial program file is deleted, and then the file name assigned to the second initial program file is changed from the second file name to the first file name. A first process for changing the file name assigned to the third initial program file from the third file name to the second file name, and the first initial program. When the file is stored in the program memory, the second initial program file is stored in the program memory. A second process for changing the file name assigned to the third initial program file from the third file name to the second file name; and When the initial program file is not stored in the program memory and the second initial program file is stored in the program memory, the file name given to the second initial program file is The third file name is changed from the second file name to the first file name, and the file name given to the third initial program file is changed from the third file name to the second file name. When the processing and the first initial program file are not stored in the program memory, the second initial program file An update including a fourth process for changing the file name assigned to the third initial program file from the third file name to the second file name if not stored in the program memory And an update process execution step executed by the CPU of the electronic device.

  In the electronic device of the present invention, when the initial program read by the boot loader is updated, a new initial program file is stored in the program memory, and the name indicates that the name is the latest version of the initial program file. In addition, the file having the name indicating that it is the latest version of the initial program file originally stored in the program memory is deleted or renamed.

  In the electronic device of the present invention, the boot loader performs a process of selecting a file having a name indicating that it is the latest version of the initial program file from the program memory and expanding it to the working memory.

  As a result, in the electronic device of the present invention, the boot loader can perform a simple start process without being aware of the version of the initial program executed at the time of start, and the execution code of the boot loader can be shortened.

  Also, in the program update method of the present invention, when updating an initial program read by a boot loader to an electronic device, a new initial program file is stored in the program memory and its name is the latest version of the initial program file. A file having a name indicating that it is present, and a file having a name indicating that it is the latest version of the initial program file originally stored in the program memory is deleted or renamed.

  Therefore, the boot loader of the electronic device can perform a process of selecting a file having a name indicating that it is the latest version of the initial program file from the program memory and expanding the file to the working memory. The boot loader can perform a simple start process without being aware of the version of the initial program executed at the time of startup, and the execution code of the boot loader can be shortened.

  As the best mode for carrying out the present invention, an electronic device incorporating a CPU (Central Processing Unit) and electronically controlled by the CPU will be described. Note that electronic devices include all devices that operate electrically, such as household appliances, office devices, audiovisual devices, mobile phones, and communication devices.

  FIG. 1 shows an internal block diagram of an electronic apparatus 10 to which the present invention is applied.

  As shown in FIG. 1, the electronic device 10 performs an electronic control target unit 11 that is a unit that is provided in the electronic device 10 and performs electronic control, and performs operation control and arithmetic processing of the electronic control target unit 11. The CPU 12 is provided with a random access memory (RAM) 13 that becomes a work area of the CPU 12 and in which program codes are expanded. The CPU 12 sequentially executes the program code expanded on the RAM 13, performs arithmetic processing based on the program code, and performs various controls on the electronic control target unit 11. The electronic control target unit 11, the CPU 12, and the RAM 13 are provided on the first bus 14, and data is transferred to each other via the first bus 14.

  The electronic device 10 receives data from the outside, a flash memory 15 that is a nonvolatile rewritable memory means, a read only memory (ROM) 16 that is a nonvolatile rewritable memory means, and the like. And a data input port 17. The flash memory 15, the ROM 16, and the data input port 17 are provided on the second bus 18, and data is transferred to each other via the second bus 17.

  In addition, the electronic device 10 includes a bus bridge 19. The bus bridge 19 performs data transfer control between the first bus 14 and the second bus 18.

  The flash memory 15 stores various operation programs that are executed by the CPU 12 as files. Among these operation programs, a file in which a program code to be executed by the CPU 12 when the system is started immediately after the power is turned on is referred to as an initial program file 21 here. The initial program file 21 can be updated from the outside via the data input port 17.

After at least one update process , two types of initial program files 21 are stored in the flash memory 15 in a normal state . One is the latest initial program file 22 in which the latest version of the program code is described, and the other is the old initial program file 23 in which the old version of the program code is described. However, only the latest initial program file 22 may be stored in the flash memory 15 at the time of factory shipment.

  In the electronic device 10, the name of the file stored in the flash memory 15 is composed of a file title and an extension indicating the type of the file. The file title and extension are connected with dots. In the electronic device 10, the name of the latest initial program file 22 and the name of the old initial program file 23 are managed in a format in which the file title is the same and only the extension is different. For example, as shown in FIG. 1, the file titles of the latest initial program file 22 and the old initial program file 23 are both “program”, the extension of the latest initial program file 22 is “run”, and the old initial program file 23 The extension is managed as “old”.

  Further, the boot loader 24 is stored in the flash memory 15 at a specific physical address. The boot loader 24 is a program in which an execution code that reads the latest initial program file 22 when the system of the electronic device 10 is activated and develops it on the RAM 13 so that the CPU 12 can execute it is described.

  In the electronic device 10 configured as described above, the boot loader 24 is stored, so that the system is gradually activated. That is, at the time of system startup, the boot loader 24 is read by the CPU 12, and the boot loader 24 is executed by the CPU 12. Subsequently, the latest initial program file 22 is read by the CPU 12 in accordance with the execution of the boot loader 24, and the program code of the latest initial program file 22 is expanded on the RAM 13. Then, when the CPU 12 executes the program code developed on the RAM 13, the startup operation of the electronic device 10 is completed.

  Furthermore, in the electronic device 10 having the above configuration, the initial program file 21 can be updated from the outside. When updating, a new version of the initial program file 21 is input from the data input port 17. Then, the input initial program file 21 is recorded in a free area on the flash memory 15, thereby completing the update. Note that the subject of the update process may be the CPU 12 or an external device. When the CPU 12 performs, for example, it is performed by executing a program for update processing stored in the ROM 16 or the like. When the external device performs, for example, the flash memory 15 is connected to its own external storage device. Recognize and process.

  Next, specific processing contents of the boot loader 24 will be described with reference to the flowchart of FIG.

  When the power of the electronic device 10 is turned on, the CPU 12 reads the boot loader 24 from the flash memory 15 and executes it, thereby performing the following processing from step S102 to step S106 (S101). The CPU 12 first detects whether or not the latest initial program file (program.run) 22 exists in the flash memory 15 (S102). If the latest initial program file (program.run) 22 exists, the CPU 12 expands the program code of the file on the RAM 13 (S105), and then starts the expanded program (S106). On the other hand, if the latest initial program file (program.run) 22 does not exist, the CPU 12 determines whether or not the old initial program file (program.old) 23 exists on the flash memory 15 (step S103). If it exists, the name of the old initial program file (program.old) 23 is changed to the name (program.run) originally assigned to the latest initial program file 22 (S104). As a result, the latest initial program file 22 is stored in the flash memory 15. Then, the CPU 12 expands the program code of the file whose name has been changed on the RAM 13 (S105), and then activates the expanded program (S106).

  As described above, the CPU 12 executes the boot loader 24 to perform the startup process.

  Next, the processing contents when the initial program file 21 is updated will be described with reference to the flowchart of FIG. Note that this processing may be performed by the external device or the CPU 12, but will be described here as being performed by the CPU 12.

  First, an update processing start command is given, and in response to this command, a new version of the initial program file 21 is input from the data input port 17. The CPU 12 assigns a temporary name to the input file and stores it in the flash memory 15 (S201). The temporary name is the same as the latest initial program file (program.run) 22 and the old initial program file (program.old) 23, but has the same file title and only the extension. For example, the file name of the temporary name is “program”, which is the same as the latest initial program file 22 and the old initial program file 23, and the extension is “tmp”.

  Subsequently, the CPU 12 detects whether or not the old initial program file (program.old) 23 exists in the flash memory 15 (S202). If it exists, the process proceeds to step S203, and if not, the process proceeds to step S206.

  In step S203, the CPU 12 detects whether or not the latest initial program file (program.run) 22 exists in the flash memory 15 (S203).

  If it is determined in step S203 that the latest initial program file (program.run) 22 exists, the process proceeds to step S208. If it is determined in step S203 that the latest initial program file (program.run) 22 does not exist, the old initial program file (program.old) 23 is deleted (S204), followed by the latest initial program file (program.run). run) 22 is changed to a name (program.old) assigned to the old initial program file 23 (step S205), and the process proceeds to step S208.

  In step S206, the CPU 12 detects whether or not the latest initial program file (program.run) 22 exists in the flash memory 15 (S206).

  If it is determined in step S206 that the latest initial program file (program.run) 22 exists, the process proceeds to step S208. If it is determined in step S206 that the latest initial program file (program.run) 22 does not exist, the name of the latest initial program file (program.run) 22 can be given to the old initial program file 23 (program.old). (Step S207), and the process proceeds to step S208.

  In step S <b> 208, the CPU 12 changes the name of the new initial program file (program.tmp) assigned with the temporary name to the name (program.run) originally assigned to the latest initial program file 22. As a result, the latest initial program file 22 is stored in the flash memory 15. Then, the CPU 12 ends the update process.

  As described above, in the electronic device 10, when updating the initial program file 21 read by the boot loader 24, the name of the new initial program file is stored as the name of the latest version file (program.run) and originally stored. Change the name of the latest version of the file to another name, or delete the file itself.

  As a result, the boot loader 24 can always read the file of the latest version as long as it reads the file with a specific name without performing the search processing of the latest version.

  As a result, the electronic device 10 can perform startup processing with a simple execution code that is not conscious of the version of the initial program file that is executed at startup, and can further shorten the execution code.

  Further, in the electronic device 10, the names of the latest initial program file 22 and the old initial program file 23 are changed only with the same file title. As a result, if only the descriptor search is performed, it is possible to determine the new version and the old version, and it is possible to simplify the processing of the boot loader.

  In the electronic device 10, the boot loader 24 is stored in the flash memory 15, but may be stored in another memory or area.

It is an internal block diagram of the electronic device to which this invention was applied. It is a figure which shows the processing flow of a boot loader. It is a figure which shows the update process flow of an initial program file.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electronic device, 11 Electronic control object part, 12 CPU, 13 RAM, 14 1st bus, 15 Flash memory, 16 ROM, 17 Data input port, 18 2nd bus, 19 Bus bridge, 21 Initial program file, 22 Latest initial program file, 23 Old initial program file, 24 Boot loader

Claims (2)

Working memory where the program code is deployed,
Shows the first and the initial program file first file name composed from the file title and extension indicating the type of the file has been applied, that than the first initial program file is new initial program file versions A second file name that is different only in extension from the first file name is assigned, and a second initial program file that is newer than the first initial program file is stored in a state that can be updated from the outside. Program memory
When the second initial program file is stored in the program memory, the second initial program file is expanded in the working memory, and the second initial program file is stored in the program memory. If not, the file name assigned to the first initial program file is changed to the second file name by changing only the extension from the first file name, and then the file name is changed. A boot memory in which a boot loader for executing a startup process for starting the expanded program is stored in a predetermined physical quantity area after expanding the first initial program file after the change to the working memory;
A process for reading boot loader system startup from the boot memory, expanded in working memory the second initial program files program code are expanded when in the program memory the second initial program files are stored When the second initial program file is not stored in the program memory, the first file name is changed from the first file name by changing only the extension of the file name given to the first initial program file. after changing to the second file name, after the first initial program after changing the file name to expand into the working memory, and start processing start the initial program extracted files, when updating, for updating Upgrade from non-volatile memory that stores programs Reads over preparative program, thereafter, after applying a third file name for the third initial program file, the latest version that is input from the outside, third imparted with the third file name When the first initial program file is stored in the program memory and the second initial program file is stored in the program memory, the second initial program file is stored in the program memory. The first initial program file is deleted, and then the file name given to the second initial program file is changed from the second file name to the first file name, and the third initial program file is deleted. The first process for changing the file name assigned to each from the third file name to the second file name When the first initial program file is stored in the program memory and the second initial program file is not stored in the program memory, the first initial program file is assigned to the third initial program file. A second process for changing the third file name to the second file name, and when the first initial program file is not stored in the program memory, the second initial program file is When stored in the program memory, the file name assigned to the second initial program file is changed from the second file name to the first file name, and to the third initial program file. Third process for changing the assigned file name from the third file name to the second file name When the first initial program file is not stored in the program memory and the second initial program file is not stored in the program memory, the first initial program file is assigned to the third initial program file. And a CPU for executing an update process including a fourth process for changing the file name from the third file name to the second file name. In a program update method for upgrading a program incorporated in an electronic device,
Shows the first and the initial program file first file name composed from the file title and extension indicating the type of the file has been applied, that than the first initial program file is new initial program file versions A second file name that is different only in extension from the first file name is assigned, and a second initial program file that is newer than the first initial program file is stored in a state that can be updated from the outside. When the second initial program file is stored in the program memory, the second initial program file is expanded in the working memory, and the second initial program file is stored in the program memory. If not, it is added to the first initial program file. File name and the after changing the second file name by changing only the extension from the first file name, the first initial program file after the change of the file name was developed in the working memory after the boot loader reads executing the CPU reads the processing of the electronic device boot loader from the boot memory which is stored in the predetermined physical quantity range the boot loader at system startup for executing the startup process to start the program developed ,
When the second initial program file is stored in the program memory, the second initial program file is expanded in a working memory where program code is expanded , and the second initial program file is stored in the program memory. If the file name is changed from the first file name to the second file name by changing only the extension of the file name given to the first initial program file when not stored, the file is changed. after deploying the name first initial program file after changing the in the working memory, and starts the process execution step of executing the expanded initial program file to that start process starts CPU of the electronic apparatus,
After the update program is read from the non-volatile memory in which the update program is stored at the time of update, and then the third file name is assigned to the third initial program file that is the latest version input from the outside. When the third initial program file assigned with the third file name is stored in the program memory, and the first initial program file is stored in the program memory, the second initial program file is stored in the program memory. If stored in the program memory, the first initial program file is deleted, and then the file name assigned to the second initial program file is changed from the second file name to the first file name. The file name is assigned to the file assigned to the third initial program file. The first process for changing the file name from the third file name to the second file name, and when the first initial program file is stored in the program memory, Second process for changing the file name given to the third initial program file from the third file name to the second file name when the initial program file is not stored in the program memory When the first initial program file is not stored in the program memory and the second initial program file is stored in the program memory, the second initial program file is stored in the second initial program file. The assigned file name is changed from the second file name to the first file name to the third initial program file. A third process for changing the file name given to the file from the third file name to the second file name, and when the first initial program file is not stored in the program memory, If the second initial program file is not stored in the program memory, the file name assigned to the third initial program file is changed from the third file name to the second file name. An update process execution step in which the CPU of the electronic device executes an update process including a fourth process.

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