JP2007316687A - Electronic equipment, program rewriting method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide electronic equipment, a program rewriting method and a program, capable of rewriting easily and surely a control program stored in a nonvolatile memory. <P>SOLUTION: The electronic equipment is provided with the rewritable nonvolatile memory 34 for storing the control program, a rewriting state storage part 38 for storing information indicating a rewriting state, of the nonvolatile memory 34, to the control program to be stored in the nonvolatile memory 34, and a CPU 30 for conducting control to rewrite the control program, when the information stored in the rewriting state storage part 38 indicates that the rewriting for the control program is not finished in the nonvolatile memory 34, referring to the rewriting state storage part 38 at startup. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technique for rewriting an electronic device control program stored in a nonvolatile memory.

  In electronic devices controlled by a computer, a control program is stored in a rewritable nonvolatile memory (flash memory or the like), and those that can rewrite (update, update) the control program as necessary have been increasing in recent years.

  However, if an error occurs during rewriting, the device is normally disabled. In order to ensure rewriting, such a program update is performed by a special engineer for a device in a relatively special field such as a disk drive for a PC (Personal Computer), an in-vehicle electronic control device, etc. (See Patent Documents 1 and 2).

JP 2004-185606 A JP 2001-135089 A

  Updating an electronic device used in such a field is an engineer who is familiar with the normal work procedure and performs the update with sufficient care, so there are few troubles. However, when a general user performs a renewal operation for consumer devices, even if the precautions are described in the instruction manual, it may not be completely observed, and the renewal operation fails. There is also. Usually, in the rewriting process, after erasing an old program in the nonvolatile memory, a new program is written. For this reason, if a write error or transmission error occurs during the rewrite process, it will not be possible to start up the electronic device again because there is no control program that operates normally. Recovery process is difficult.

  In view of the above circumstances, an object of the present invention is to provide an electronic device, a program rewriting method, and a program that can easily and reliably rewrite a control program stored in a nonvolatile memory.

  In order to achieve the above object, an electronic device according to a first aspect of the present invention includes a rewritable nonvolatile memory that stores a control program, and the nonvolatile memory that stores the control program to be stored in the nonvolatile memory. The rewrite state storage unit that stores information indicating the rewrite state of the memory, and the rewrite state storage unit is referred to at the time of startup, and the information stored in the rewrite state storage unit has been rewritten to the control program in the nonvolatile memory A control unit that performs control so as to rewrite the control program when indicating that the control program is not performed.

  In the above configuration, the control unit controls to rewrite the information in the rewrite state storage unit to information indicating that the rewrite of the control program in the nonvolatile memory is completed when the control program rewrite is normally completed. .

  In the above configuration, the control unit refers to the rewrite state storage unit at startup, and when the information stored in the rewrite state storage unit indicates that the rewrite of the control program has been completed, the control program Control based on

In the above configuration, for example, the rewrite state storage unit may be battery driven.
Further, the rewrite state storage unit may be provided in a part of the nonvolatile memory.

  In order to achieve the above object, a program rewriting method according to a second aspect of the present invention provides a control program to be updated and stored in a rewritable nonvolatile memory in which a control program is stored. A rewrite state storage step for storing information indicating a rewrite state, and when the information stored in the rewrite state storage step at the start indicates that the rewrite of the control program in the nonvolatile memory has not been completed, And a control step for performing control.

  In order to achieve the above object, the program according to the third aspect of the present invention is a rewrite state of the non-volatile memory into a control program to be updated and stored in the rewritable non-volatile memory storing the control program. When the information stored in the rewrite state storage procedure for storing the information indicating the rewrite state and the information stored in the rewrite state storage procedure at the start indicate that the rewrite of the control program in the nonvolatile memory has not been completed, the control program is rewritten. And a control procedure for controlling the computer to be executed.

That is, the present invention can be easily realized by causing the electronic device such as a playback device or a computer device to read the program and executing a series of processes.
Furthermore, the program is encoded and transmitted as a program code signal superimposed on a carrier wave, and the program code signal superimposed on the carrier wave is received, decoded into the original program, and executed by a computer device or the like. The technique in the present invention can be easily implemented. It is also possible to record a program downloaded and decrypted in such a computer device or the like on a CD-R (Compact Disc Rewritable) or the like and install it in an electronic device such as a playback device.

  ADVANTAGE OF THE INVENTION According to this invention, the electronic device which can rewrite the control program stored in the non-volatile memory easily and reliably, the program rewriting method, and a program are provided.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiment, an example in which the present invention is applied to a consumer playback device, particularly a compact disc player will be described.

  FIG. 1 shows the configuration of a playback apparatus 10 according to an embodiment of the present invention. As shown in FIG. 1, the playback device 10 includes a mechanical unit 12, an operation unit 14, and a system control unit 16.

The mechanical unit 12 includes a disk drive unit 18, a drive control unit 20, and a D / A (Digital to Analog) conversion unit 22.
The disk drive unit 18 includes a general disk loading mechanism and is loaded with a compact disk. The disk drive unit 18 may be capable of loading a plurality of compact disks.

  The drive control unit 20 includes a general disk drive control circuit, and performs seeking of a designated track of the compact disk, decoding of a read digital signal, and the like.

The D / A conversion unit 22 converts the digital signal read from the compact disc and decoded by the drive control unit 20 into an analog signal, and outputs the analog signal to an output terminal 24 connected to an external device such as a speaker. Of course, when a speaker or the like is built in, sound may be emitted through these.
When an output interface compatible with digital output is used, the D / A converter 22 does not convert it into an analog signal, but converts it into a predetermined digital interface format and outputs it.

  The operation unit 14 includes a display unit 26 and an operation input unit 28.

  The display unit 26 is composed of a liquid crystal display device or the like, and displays information related to the operation state, function, etc. of the playback device 10.

  The operation input unit 28 includes a power input button, a playback button, a stop button, and the like, and accepts an operation instruction input from an operator. The operation input unit 28 may include input means such as a remote controller and a touch panel.

  The system control unit 16 includes a CPU (Central Processing Unit) 30, a communication unit 32, a nonvolatile memory 34, a rewrite control unit 36, and a rewrite state storage unit 38.

  The CPU 30 controls the reproduction operation according to the input from the operation input unit 28 based on a reproduction control program stored in the nonvolatile memory 34 described later. In addition, the CPU 30 displays an operation state on the display unit 26.

  The communication unit 32 includes serial communication interfaces such as RS (Recommended Standard) 232, RS422, and RS485, and is configured to be connectable to an external PC or the like. Via the communication unit 32, remote control of the playback apparatus 10 and reception of an update program from a PC or the like is performed.

  For example, the PC connected to the communication unit 32 stores a control program for the playback device 10 to be updated downloaded from a website of the playback device 10 manufacturer, for example. Not only the control program but also an updater program that functions in the same manner as the rewrite control unit 36 may be downloaded and stored.

The nonvolatile memory 34 includes a rewritable nonvolatile memory 34, for example, a semiconductor memory such as a flash memory, an EPROM (Erasable Programmable Read Only Memory), an EEPROM (Electrically Erasable ROM), an FeRAM (Ferroelectric Random Access Memory), and the like. The
The nonvolatile memory 34 has a plurality of use areas, and a reproduction control program and a rewrite control program are stored in each of the areas.

  The rewrite control unit 36 performs a process of rewriting the reproduction control program stored in the nonvolatile memory 34 based on the rewrite control program stored in the nonvolatile memory 34 under the control of the CPU 30. The program rewriting process includes a verification process such as an error check of the reproduction control program written in the nonvolatile memory 34.

  The rewrite state storage unit 38 stores information indicating whether or not the reproduction control program in the nonvolatile memory 34 is in a rewritten state. The CPU 30 stores in the rewrite state storage unit 38 information indicating that the rewrite control unit 36 is in the rewrite state when the rewrite control unit 36 starts rewriting, in other words, information indicating that rewrite is continuing and has not ended. To do.

  When the CPU 30 confirms that the rewriting of the program has been normally completed, the rewrite state storage unit is updated with information indicating that the rewriting state storage unit 38 is not in the rewriting state, in other words, the rewriting has been completed normally. Rewrite 38.

  The rewrite state storage unit 38 is independently driven by a battery or the like, and the stored information is retained even when the playback apparatus 10 is powered off. Accordingly, even when the rewriting of the reproduction control program is not normally completed and is forcibly terminated, the information indicating the rewriting state stored in the rewriting state storage unit 38 is retained.

  The CPU 30 refers to the rewrite state storage unit 38 when the playback device 10 is activated, and determines whether or not the rewrite process has been normally completed when the previous end. Except for the case where information indicating that rewriting is being performed is stored in the rewrite state storage unit 38, the CPU 30 controls the reproduction operation as usual according to the reproduction control program in the nonvolatile memory 34.

  On the other hand, when information indicating that rewriting is being performed is stored in the rewriting state storage unit 38, the CPU 30 determines that rewriting has not been completed at the end of the previous time. At this time, the CPU 30 controls the rewrite control unit 36 so that the rewrite process is restarted from the beginning according to the rewrite control program of the nonvolatile memory 34. The rewrite control unit 36 erases the reproduction control program stored in the predetermined area of the nonvolatile memory 34, and then writes a new reproduction control program in the area.

  Hereinafter, the operation of the playback apparatus 10 according to the present embodiment will be described. FIG. 2 shows a flowchart for explaining the operation of the playback apparatus 10 according to the present embodiment. The flowchart shown in the figure is an example, and any flowchart may be used as long as the same result is realized.

  When the operation input unit 28 receives an input for turning on the power, the CPU 30 initializes a necessary portion (step S101). After completion of initialization, the CPU 30 refers to the rewrite state storage unit 38 and determines whether or not the playback device 10 was in a rewrite state at the end of the previous time (step S102).

  When the information stored in the rewrite state storage unit 38 is not in the rewrite state, that is, indicates that the rewrite process has been completed normally (or the rewrite process has not been performed) (NO in step S102). The CPU 30 determines that the operation control program is normally stored in the nonvolatile memory 34, performs initialization processing necessary for performing the reproduction operation, and performs normal operations (steps S103 and S104). Thereafter, the CPU 30 performs a normal operation unless receiving a program rewrite request from a PC or the like.

  When the information stored in the rewrite state storage unit 38 indicates that the information is in the rewrite state (step S102: YES), the CPU 30 performs a program rewrite process after S108 described later. For example, when the rewriting process described later is not normally terminated at the time of the previous activation (power ON), but is terminated forcibly or by the operator's operation (power OFF), the rewriting state storage unit 38 stores the rewriting state. Therefore, the program rewriting process described later is performed again.

  When a program rewrite request is received from the PC or the like via the communication unit 32 (step S105: YES), the CPU 30 stops the reproduction if it is being reproduced, and the compact loaded in the disk drive unit 18 If there is a disc, it is ejected (step S106). This is to avoid inconveniences such as sudden interruption of reproduction and inability to take out the disc by shifting to the program rewriting process.

  Next, the CPU 30 stores, in the rewrite state storage unit 38, information indicating that it is in the rewrite state, that is, that the rewrite process has not ended normally (step S107). As a result, in the rewrite state storage unit 38, information indicating that the rewrite state is not present is rewritten to information indicating that the rewrite state is present. Further, the CPU 30 controls the display unit 26 to display that it is in a rewritten state (step S108).

  Next, the CPU 30 controls the rewrite control unit 36 and erases the reproduction control program stored in the nonvolatile memory 34 (step S109). Thereafter, the CPU 30 receives the reproduction control program data from the PC or the like via the communication unit 32, and sequentially writes the data in a predetermined area of the nonvolatile memory 34 (steps S110, S111, S112).

  After completion of the writing, the rewrite control unit 36 checks whether or not the reproduction control program has been normally written using a checksum of the stored program data (step S113). When all the program data is normally written (step S114: YES), the CPU 30 rewrites the information stored in the rewrite state storage unit 38 to information indicating that the rewrite state is not present (step S115). Thereafter, the CPU 30 performs a normal reproduction operation based on the updated reproduction control unit program (step S104).

  When the program data is not normally written (step S114: NO), the CPU 30 displays a display indicating that an error has occurred and the rewriting operation is necessary again without updating the information in the rewriting state storage unit 38. The display unit 26 is controlled to perform (step S116). Thereafter, the process returns to the process of step S108 and the program update process is performed again.

  According to the above process, for example, when the rewriting process is performed at the previous activation but an error occurs and the process is forcibly terminated, the rewriting process is started again at the next activation. Only when it is verified that the rewriting process has been normally completed, the rewriting state storage unit 38 stores that the rewriting has been normally completed.

  Thereby, at the time of restart, it is surely avoided that the processing according to the playback control program that has already been erased or has not been written normally is tried and the playback device 10 becomes inoperable. Therefore, the operator can easily and surely update the control program without having a dedicated ROM writer or the like and thus having specialized knowledge.

  In the above embodiment, the rewrite state storage unit 38 that stores information indicating the rewrite state and is backed up by the battery is provided. However, the method for storing the rewrite state is not limited to this. For example, a value other than the value set after erasing the program may be written to the last address of the area storing the reproduction control program in the nonvolatile memory 34. In this case, the CPU 30 refers to the value as information indicating the rewrite state at the time of activation, and performs a rewrite operation or a normal reproduction operation.

In the above embodiment, the example in which the present invention is applied to the reproducing apparatus 10, particularly the compact disc player has been described. However, the present invention is not limited to this, and the present invention can be applied to any electronic device in which a control program is stored in the rewritable nonvolatile memory 34.
Furthermore, a program code signal in which processing according to the present invention is described in a predetermined language may be distributed via a carrier wave or a recording medium, and this may be combined and installed in an electronic device.

It is a block diagram which shows the structure of the reproducing | regenerating apparatus 10 concerning embodiment of this invention. It is a flowchart which shows operation | movement of the reproducing | regenerating apparatus 10 concerning embodiment of this invention.

Explanation of symbols

10: playback device, 12: mechanical unit, 14: operation unit, 16: system control unit, 30: CPU, 32: communication unit, 34: nonvolatile memory, 36: rewrite control unit, 38: rewrite state storage unit

Claims (7)

A rewritable nonvolatile memory for storing the control program;
A rewrite state storage unit for storing information indicating a rewrite state of the nonvolatile memory to a control program to be stored in the nonvolatile memory;
Control is performed to rewrite the control program when the rewrite state storage unit is referred to at the time of start-up and the information stored in the rewrite state storage unit indicates that the rewrite of the control program in the nonvolatile memory has not been completed. A control unit,
An electronic device characterized by comprising:   The control unit controls to rewrite information in the rewrite state storage unit to information indicating that rewriting of the control program in the nonvolatile memory is completed when the control program rewriting is normally completed. The electronic device according to claim 1.   The control unit refers to the rewrite state storage unit at the time of startup, and when the information stored in the rewrite state storage unit indicates that the rewrite of the control program has been completed, the control unit performs control based on the control program. The electronic device according to claim 1, wherein the electronic device is performed.   The electronic device according to claim 1, wherein the rewrite state storage unit is battery-driven.   The electronic device according to claim 1, wherein the rewrite state storage unit is provided in a part of the nonvolatile memory. A rewrite state storage step for storing information indicating a rewrite state of the nonvolatile memory to a control program to be updated and stored in the rewritable nonvolatile memory in which the control program is stored;
A control step for controlling to rewrite the control program when the information stored in the rewrite state storage step at the start indicates that the rewrite of the control program in the nonvolatile memory is not completed;
A program rewriting method characterized by comprising: A rewrite state storage procedure for storing information indicating a rewrite state of the non-volatile memory into a control program to be updated and stored in the rewritable non-volatile memory in which the control program is stored;
A control procedure for controlling to rewrite the control program when the information stored in the rewrite status storage procedure at the start indicates that the rewrite of the control program in the nonvolatile memory is not completed;
A program characterized by causing a computer to execute.

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