JP2000163274A - Electronic equipment and recording medium with rom data monitoring program recorded thereon - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a malfunction of a control object device and also to protect the control object device by interrupting power supply to the control object device when an abnormality in a control program stored in a flash ROM is detected. SOLUTION: A controller 1 finds the check sum value of a control program 14 stored in a flash ROM 13 and repeatedly executes that the found check sum value of the program 14 is supplied to a monitoring device within a preliminarily set period. The monitoring device 3 judges that an abnormality exists in the program 14 based on such matters that the check sum value is not supplied from the controller 1 within a preliminarily set period and also that the check sum value changes and interrupts power feeding to the control object device 5 by controlling a power supplying and interrupting part 4 in an interruption state. The device 3 restores the program 14 by writing a backup program stored in a backup program storing part 2 to the flash ROM 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a flash RO.
When an abnormality is detected in the control program stored in the M, the power supply to the control target device is cut off to prevent malfunction of the control target device, and to the flash ROM. The present invention relates to an electronic device capable of automatically restoring a stored control program, and a recording medium storing a ROM data monitoring program.

[0002]

2. Description of the Related Art In recent years, there has been an increasing number of home appliances and the like in which devices are controlled by a microcomputer (microcomputer). In particular, in a TV (television receiver), various functions are digitized, and it is certain that control to be performed by a microcomputer will increase in the future. But,
Many of the currently used control microcomputers use a non-rewritable storage element (for example, a mask ROM). On the other hand, since the flash ROM is rewritable, the data can be updated even after the microcomputer is incorporated in the set. But Flash ROM
In some cases, the contents written in the flash ROM may be erased or the contents (data) may change due to disturbance or the like.

For this reason, various techniques for monitoring a control program and the like have been proposed. For example, JP-A-5-15
Japanese Patent Publication No. 1105 discloses a fault monitoring circuit for monitoring faults of a processor and a storage device. This fault monitoring circuit generates an arbitrary address value for monitoring at a fixed cycle by a storage device monitoring means to perform a sum check monitoring, and also monitors a time period of an address generation cycle of a processor by a watchdog timer, thereby storing the data. It monitors the failure of the device and monitors the runaway of the processor.

[0004] Also, Japanese Patent Application Laid-Open No. 6-52066 discloses that
There is described an EEPROM monitoring circuit capable of performing monitoring at a short cycle by constantly monitoring the EEPROM with hardware and reducing the load on software.

Further, Japanese Patent Laid-Open No. 8-320834 discloses a method for checking data for detecting an error in an execution program, which has a checksum of a horizontal direction and a vertical method for each data of the execution program. At the start of the program, the validity of the execution program is confirmed by these, and when an error is found, a flash RO that automatically corrects the execution program
M automatic recovery method is described.

[0006]

Problems to be Solved by the Invention
The fault monitoring circuit described in Japanese Patent Application Laid-Open No. 5-52103 performs a fault monitoring of a storage device and a runaway of a processor, and can generate an alarm when an abnormality is detected. However,
There is a possibility that the control target device will be in an abnormal operation state due to the destruction of the control program. Similarly, in the EEPROM monitoring circuit described in Japanese Patent Application Laid-Open No. 6-52066, there is a possibility that the control target device may malfunction due to the destruction of the control program. In the flash ROM automatic recovery method described in Japanese Patent Application Laid-Open No. 8-320834, when a control target device enters an abnormal operating state (malfunctioning state) due to destruction of a control program, the execution program is automatically corrected. During this time, there is a risk that the malfunctioning state of the controlled device will continue. Further, in a malfunction state, unnecessary power is consumed, which is not preferable.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to solve such a problem. When an abnormality is detected in a control program stored in a flash ROM, power supply to a controlled device is cut off. Electronic equipment that prevents malfunction of the control target device by performing
It is an object of the present invention to provide a recording medium recording a ROM data monitoring program. Further, when it is detected that the control program stored in the flash ROM is abnormal, the power supply to the control target device is cut off and the control program stored in the flash ROM can be automatically restored. Electronic equipment, and
It is an object of the present invention to provide a recording medium recording a ROM data monitoring program.

[0008]

According to another aspect of the present invention, there is provided an electronic apparatus that controls an operation of a control target device based on a control program stored in a flash ROM; A power supply / cutoff unit for supplying / cutting power to the device, and a flash RO
A monitoring device for detecting an abnormality in the control program stored in the flash memory M. When the monitoring device detects an abnormality in the control program stored in the flash ROM, control is performed via a power supply / cutoff unit. The power supply to the target device is shut off.

An electronic apparatus according to claim 1 is a flash R
When an abnormality occurs in the control program stored in the OM, the abnormality is detected by the monitoring device, and power supply to the control target device is cut off. Therefore, when the control program is destroyed or the like, the power supply to the control target device is cut off, so that the control target device does not malfunction and unnecessary power is not consumed.

According to a second aspect of the present invention, in the electronic device according to the first aspect, the control device obtains a checksum value of the control program stored in the flash ROM, and sends the obtained checksum value to the monitoring device. The supplying is repeatedly performed within a preset period, and the monitoring device checks that the checksum value is not supplied within the preset period from the control device, and checksum value supplied from the control device. Is determined to have an abnormality in the control program stored in the flash ROM based on the change of the control program.

When a part of the control program is erased or the data is changed (data is garbled), the checksum value of the control program changes. Destruction)
Can be detected. Further, the monitoring device can detect an abnormality (eg, destruction) of the control program based on the fact that the checksum value is not supplied from the control device within a preset period.

According to a third aspect of the present invention, there is provided an electronic apparatus comprising:
A control device for controlling the operation of the controlled device based on a control program stored in the OM, a power supply / cutoff unit for supplying / cutting power to the controlled device, and a control program stored in the flash ROM A backup program storage unit for storing a backup program having the same contents as the above, and a power supply / supply when an abnormality of the control program stored in the flash ROM is detected.
The power supply to the control target device is cut off via the cutoff unit, and the backup program stored in the backup program storage unit is stored in the flash ROM.
And a monitoring device for restoring the control program stored in the flash ROM by writing to the flash ROM.

According to a third aspect of the present invention, there is provided an electronic apparatus comprising:
If the control program stored in the OM is destroyed or the like, the power supply to the control target device is cut off.
The control target device does not malfunction and unnecessary power is not consumed. Further, since the backup program is provided in the backup program storage unit, the control program stored in the flash ROM can be restored by writing the backup program into the flash ROM.

According to a fourth aspect of the present invention, in the electronic device according to the third aspect, the control device obtains a checksum value of the control program stored in the flash ROM, and sends the obtained checksum value to the monitoring device. The supplying is repeatedly performed within a preset period, and the monitoring device checks that the checksum value is not supplied within the preset period from the control device, and checksum value supplied from the control device. Is determined to have an abnormality in the control program stored in the flash ROM based on the change of the control program.

When a part of the control program is erased or the data is changed (data is garbled), the checksum value changes. Therefore, the monitoring device determines whether the control program is abnormal (destruction or the like) based on the change in the checksum value. Can be detected. Further, the monitoring device can detect an abnormality (eg, destruction) of the control program based on the fact that the checksum value is not supplied from the control device within a preset period.

According to a fifth aspect of the present invention, in the electronic device according to the third aspect, the monitoring device collates the control program stored in the flash ROM with the backup program stored in the backup program storage. Thus, an abnormality of the control program stored in the flash ROM is detected.

According to a fifth aspect of the present invention, there is provided an electronic apparatus comprising:
By comparing the control program stored in the OM with the backup program stored in the backup program storage unit, an abnormality in the control program stored in the flash ROM can be detected. Since the control device does not need to obtain the checksum value of the control program stored in the flash ROM, the load on the control device is reduced.

According to a sixth aspect of the present invention, there is provided a recording medium in which a ROM data monitoring program is recorded, wherein a control program monitoring means for detecting an abnormality in a control program stored in a flash ROM, and a control program monitoring means for detecting an abnormality in the control program. A ROM data monitoring program for causing a computer to execute a power shutoff means for interrupting power supply to a controlled device controlled based on the control program when detected is recorded on a computer readable recording medium. Features.

According to a sixth aspect of the present invention, a recording medium storing the ROM data monitoring program causes a computer to execute an operation of detecting an abnormality of a control program stored in a flash ROM and cutting off power supply to a control target device. Can be. Therefore, when the control program is destroyed or the like, the power supply to the control target device is cut off, so that the control target device does not malfunction and unnecessary power is not consumed.

According to a seventh aspect of the present invention, there is provided a recording medium in which a ROM data monitoring program is recorded, wherein a control program monitoring means for detecting an abnormality in the control program stored in the flash ROM, and a control program monitoring means for detecting an abnormality in the control program. A power supply shutoff means for interrupting power supply to a controlled device controlled based on the control program when detected, and a control program for restoring the control program by writing a backup program backed up in an EEPROM to a flash ROM A ROM data monitoring program for causing a computer to execute the recovery means is recorded on a computer-readable recording medium.

According to a seventh aspect of the present invention, there is provided a ROM data monitoring program for detecting an abnormality in a control program stored in a flash ROM, interrupting power supply to a device to be controlled, and writing a backup program in the flash ROM. Thus, the computer can execute an operation for restoring the control program. Therefore, when the control program is destroyed or the like, the power supply to the control target device is cut off, so that the control target device does not malfunction and unnecessary power is not consumed. Further, the destroyed control program can be automatically restored.

[0022]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a block diagram of an electronic apparatus according to the present invention. An electronic apparatus according to the present invention includes a control device (control microcomputer) 1, a backup program storage (EEPROM) 2, a monitoring device (monitoring microcomputer) 3,
A power supply / interruption unit 4, a control target device (control target circuit) 5, a device power source 6, a microcomputer power source 7, a main power switch 8, and a control device power source relay unit 9. The control device 1, the backup program storage unit 2, the monitoring device 3, and the control target device 5 are connected via a bus (address / data / control bus) 10, respectively.

The control device 1 is configured using a microcomputer. The control device 1 includes a power supply control port 11, a data input / output bus port group 12, and a flash ROM 13 in which data can be electrically rewritten. The flash ROM 13 stores a control program 14 for operating the control device 1.
The control device 1 controls the supply of the device power supply 6 to the control target device 5 and the operation of the control target device 5 based on the control program 14 stored in the flash ROM 13. Specifically, by outputting power supply command information from the power supply port 11, the power supply / shutoff unit 4 is controlled to a power supply state, the apparatus power supply 6 is supplied to the control target apparatus 5, and the control target apparatus 5 is controlled. While making it operable,
Various control commands are supplied to the control target device 5 via the data input / output bus port group 12 to control the operation state of the control target device 5. Further, the control device 1 includes a data input / output bus 1
A predetermined operation control is performed on the basis of various operation input information and device state information supplied from the control target device 5 through the control target 2.

The backup program storage section 2 is constructed using an electrically rewritable EEPROM. This backup program storage unit 2
A backup program storage area 21 and a check result storage area 22 are provided. In the backup program storage area 21, a control programmer having the same contents as the control program 14 stored in the flash ROM 13 is stored as a backup programmer. The check result storage area 22 stores information (data) indicating whether the control program 14 stored in the flash ROM 13 is normal or abnormal.

The monitoring device 3 is configured using a microcomputer whose monitoring control program is not rewritable. The monitoring device 3 includes a power cutoff control port 31,
A data input / output bus port group 32 and a power relay control port 33 are provided. The monitoring device 3 monitors the control program 14 stored in the flash ROM 13 in the control device 1 and the data in the backup program storage 2, and when an abnormality of the control program 14 is detected, It has a function of interrupting the supply of the device power supply 6 to the device 5. When an abnormality in the control program 14 is detected, the monitoring device 3 writes the backup program stored in the backup program storage area 21 to the flash ROM 13 in the control device 1 so that the monitoring program 3 A function for restoring the control program 14 is provided.

The power supply / interruption unit 4 includes a relay for supplying power to the apparatus, a relay operation control circuit, and the like. The power supply / interruption unit 4 is provided with a power interruption control port 31 of the monitoring device 3.
When the power supply cut-off command information is supplied from the power supply, the power supply to the control target device 5 is cut off. Power supply / interruption unit 4
When power supply command information is not supplied from the power supply control port 31 of the monitoring device 3 and power supply command information is supplied from the power supply control port 11 of the control device 1, the device power supply 6 is controlled by the control target device. 5 and the power supply to the controlled device 5 is stopped when the power supply stop command information is supplied.

The control target device 5 includes various hardware and the like controlled by the control device 1. Equipment power supply 6
Is for supplying power to the control target device 5. The microcomputer power supply 7 supplies power to the control device 1 and the monitoring device 3. The main power switch 8 is used to supply / disconnect the microcomputer power supply 7 to / from the monitoring device 3. The monitoring device 3 includes a power-on reset circuit and the like, and starts operation of the monitoring device 3 after being initialized by turning on the power.

The power relay unit 9 for the control device includes a relay and a drive circuit for the relay. This power relay unit 9 for the control device
When the power supply command information is supplied from the power supply relay control port 33 of the monitoring device 3, the relay contact is turned on to supply the microcomputer power supply 7 to the control device 1, and the control is performed when the power supply stop command information is supplied. The power supply to the device 1 is stopped. The control device 1 includes a power-on reset circuit and the like.
Start operation.

When the main power switch 8 is turned on, the microcomputer power 7 is supplied to the monitoring device 3 and the monitoring device 3 is activated. The monitoring device 3 reads out the backup programmer stored in the backup program storage area 21 in the backup program storage unit 2 via the bus 10, obtains the checksum value of the backup programmer, and displays the obtained checksum value in the monitoring device 3. In a register or the like. The monitoring device 3 may store the checksum value of the backup programmer in a checksum value storage area (not shown) in the backup program storage unit 2.

Next, the monitoring device 3 reads the check result stored in the check result storage area 22 in the backup program storage unit 2 via the bus 10. When the check result is normal, the monitoring device 3
0 is supplied to the control device 1 via the power supply relay control port 33, and after the control device 1 is set to a state where the control operation can be performed, the power supply relay section 9 for the control device is provided. To the power supply state and control device 1
To the microcomputer power supply 7. Thereby, the control device 1 starts the operation control of the control target device 5 based on the control program 14 stored in the flash ROM 13.

When the control program 14 that defines the operation of the control device 1 is destroyed, there is a possibility that the control target device 5 malfunctions, for example, by transmitting illegal data to the control target device 5. Therefore, the operation of the control device 1 is monitored by the monitoring device 3, and when the operation of the control device 1 becomes abnormal, the power supply to the control target device 5 is cut off to protect the control target device 5.

For this reason, the control program 14 determines the checksum value of the control program 14 and performs an operation of supplying the obtained checksum value to the monitoring device 32 (hereinafter referred to as periodic communication) within a predetermined time interval. There is a program that repeats with. The monitoring device 3 controls the control program 14 stored in the flash ROM 13 based on the fact that the checksum value is repeatedly supplied from the control device 1 within a predetermined time interval, and based on the supplied checksum value. Is determined to be normal. That is, if there is no regular communication from the control device 1 within a predetermined time interval, the monitoring device 3 determines that the control program 14 has been destroyed. Further, when the checksum value supplied by the periodic communication changes from the previous value or when the checksum value differs from the checksum value of the backup program, the monitoring program 3 destroys the control program 14. And judge.

The timing at which the control device 1 performs regular communication is immediately before the control device 1 transmits control data to the control target device 5. As described above, by performing the periodic communication before transmitting the control data to the control target device 5, the monitoring device 3 controls the illegal control data before the illegal control data is supplied to the control target device 5 due to the destruction of the control program 14. When the destruction of the program 14 is detected and the power supply / cutoff unit 4 is turned off, the supply of the device power source 6 to the control target device 5 is cut off, and the control target device 5 enters an abnormal operation state. Is prevented beforehand.

In a home electronic device or the like, the same data is periodically supplied to the same circuit or the like in order to promptly recover from a malfunction due to the influence of noise or the like (so-called refresh operation). May be performed immediately before the monitoring device 3. In this case, the monitoring device 3 matches the timing of confirming that there has been regular communication from the control device 1 with the interval at which the control device 1 performs the refresh operation.

When the monitoring device 3 detects that there is no regular communication from the control device 1 or detects an abnormality in the control program 14 stored in the flash ROM 14 based on a change in the checksum value or the like, the monitoring device 3 Power cutoff command information is output from the cutoff control port 31 to control the power supply / cutoff unit 4 to a power supply cutoff state, and
The data indicating that the control program 14 is abnormal is written to the check result storage area in the backup program storage unit 2 via.

After the main power switch 8 is turned on, the monitoring device 3 reads the check result stored in the check result storage area 22 in the backup program storage unit 2, and the control program 14 is abnormal based on the check result. When recognizing that, the monitoring device 3 reads the control program (backup program) stored in the backup program storage area 21 and
To the flash ROM 13 in the memory. Thus, the control program 14 in the flash ROM 13 is restored. After restoring the control program 14, the monitoring device 3 outputs energization command information from the power relay control port 33, puts the control device power relay 9 into a power supply state, and supplies the microcomputer power 7 to the control device 1. The control operation of the control device 1 is started.

The monitoring device 3 compares the control program 14 stored in the flash ROM 13 with the backup program stored in the backup program storage area 21 in the initial state when the main power switch 8 is turned on. If the control program 14 is destroyed, the backup program is
After writing to the OM 13, the control operation of the control device 1 may be started.

When the check result is normal, the monitoring device 3 supplies command information for permitting the control operation to the control device 1 via the bus 10 and sets the control device 1 in a state where the control operation can be performed. Thereafter, the power supply relay unit 9 for the control device is controlled to the power supply state via the power supply relay control port 33 to supply the power supply 7 for the microcomputer to the control device 1. Thereby, the control device 1 starts the operation control of the control target device 5 based on the control program 14 stored in the flash ROM 13.

FIGS. 2 and 3 are flowcharts showing the control program monitoring and recovery operation of the electronic device according to the present invention. FIG. 2 shows the operation of the startup check processing, and FIG.
Indicates the operation of the non-flash ROM monitoring process.

When the main power switch 8 shown in FIG. 1 is in the OFF state, power is not supplied to any of the control device 1, the monitoring device 3, and the control target device 5. When the main power switch 8 is turned on, the microcomputer power 7 is supplied to the monitoring device 3, and the monitoring device 3 is reset and started (step S1). At this point, only the monitoring device 3 is supplied with power. When starting the processing, the monitoring device 3 reads the check result stored in the check result storage area in the backup program storage unit 2 (step S2), and based on the contents of the check result, the control program stored in the flash ROM 14. Is normal or not (step S3).

If the control program 14 is normal, the monitoring device 3 sets a state necessary for the control device 1 to perform a control operation (step S4), and supplies the power to the control device via the power relay control port 33. The relay unit 9 is controlled to be energized (step S5). As a result, the microcomputer power supply 7 is supplied to the control device 1, and the control device 1 is reset-started.

If it is determined in step S3 that the control program 14 is abnormal, the monitoring device 3 sets data for enabling the flash ROM 13 in the control device 1 to write data (step S6). Then, the monitoring device 3 controls the power relay unit 9 for the control device to be in an energized state via the power relay control port 33 (step S7). Thereby, the control device 1 is reset-started. Since the flash ROM 13 is set in the write permission state in step S6, the control device 1 does not start the control operation for the control target device 5 but waits in a state where the bus 10 is released. The monitoring device 3 reads the backup program data stored in the backup program storage unit 21 and writes the read program data to the flash ROM 13 (Step S
8). As a result, the control program 14 stored in the flash ROM 13 is restored. Flash RO
When the writing to M13 is completed, the monitoring device 3 controls the power relay unit 9 for the control device to a non-energized state via the power relay control port 33, and temporarily shuts off the power supply to the control device 1 (step S9).

The monitoring device 3 performs steps S6 to S
When the flash ROM restoration processing up to 9 is completed, a state necessary for the control device 1 to perform the control operation is set in step S4, and then in step S5, the power relay unit 9 for the control device is connected via the power relay control port 33. Is controlled to an energized state. As a result, the microcomputer power supply 7 is supplied to the control device 1, and the control device 1 is reset-started.
Since the control operation is set to be performed in step S <b> 4, control device 1 starts the control operation based on control program 14 stored in flash ROM 13.
Specifically, the power supply / cutoff unit 4 is controlled to be in a power supply state via the power supply control port 11 to supply the device power supply 6 to the control target device 5 and to control the operation of the control target device 5. .

When the control device 1 starts the control operation based on the control program 14, the monitoring device 3 starts the ROM operation shown in FIG.
Perform monitoring processing. The monitoring device 3 monitors whether or not regular communication is being performed from the control device 1 in step S10. If there is no regular communication from the control device 1 within a predetermined time interval, the monitoring device 3 determines that the control program 14 has been destroyed, and sets the power supply / cutoff unit 4 to the cutoff state to set the control target device. The supply of the device power supply 6 to the power supply 5 is cut off (step S11). Then, the monitoring device 3 writes data indicating that the control program 14 is abnormal in the check result storage area 22 in step S12.

If the regular communication is being executed, the monitoring device 3 determines whether the checksum value supplied from the control device 1 by the regular communication is normal (step S1).
3). If the checksum value is not normal, the monitoring device 3 shuts off power supply to the control target device 5 in step S11, and sends data indicating that the control program 14 is abnormal to the check result storage area 22 in step S12. Write.

If it is determined in step S13 that the checksum value is normal, the monitoring device 3 proceeds to step S1.
In step 4, it is checked whether the content of the check result storage area 22 is data indicating that the control program 14 is normal. When the content of the check result storage area 22 is data indicating that the control program 14 is abnormal, the monitoring device 3 converts the data indicating that the control program 14 is normal to the check result storage area 2.
2 (step S15).

The control device 3 repeats the ROM monitoring process shown in steps S10 to S15, thereby controlling the control program 14 stored in the flash ROM 13.
And continuously monitors the operation of the control device 1 that is operating at.
Therefore, when the operation of the control device 1 becomes abnormal due to the destruction of the control program 14 or the failure of the control device 1, the abnormality is promptly detected, and the power supply to the control target device 5 is cut off to control the control target device 5. The device 5 is prevented from becoming malfunctioning or the like.

With the above configuration and operation, the electronic device according to the present invention can operate normally even if a catastrophic failure such as the destruction of the control program 14 stored in the flash ROM 13 occurs. In other words, it is possible to prevent the operation state from being changed, and to protect the control target device 5. Further, since the backup program is provided in the backup program storage unit 2, even if the control program 14 stored in the flash ROM 13 is destroyed, the backup program is written into the flash ROM 13 so that the control program 14 is written.
Can be restored. Further, since the electronic device according to the present invention includes the independent monitoring device 3, even if a failure occurs in hardware such as a microcomputer constituting the control device 1, the operation of the monitoring device 3 is not abnormal. Unless otherwise, the control target device 5 can be protected.

In the present embodiment, an example has been described in which the power supply to the control device 1 is performed after the operation state of the control device 1 is set from the monitoring device 3 side, but the power supply to the control device 1 is performed. After that, the operation state of the control device 1 may be set. For example, the monitoring device 3 controls the control power supply relay unit 9 to be in a power supply state via the power supply relay control port 33, and then controls the flash ROM 13 via the bus 10.
Information that specifies a write mode for writing to the memory or information that specifies a control operation may be output. In this case, the control device 1 reads the operation mode information supplied from the monitoring device 3 in the initial setting process after the power is supplied, and if the operation mode information specifies the write mode to the flash ROM 13, A state in which writing to the ROM 13 is possible is set, and when the operation mode information specifies a control operation, a control operation based on the control program 14 is started.

Further, in the present embodiment, an example has been described in which the control program 14 is automatically restored when it is detected that the control program 14 in the flash ROM 13 is abnormal when the main power switch 8 is turned on. When the abnormality of the control program 14 is detected, the control program 1
4 may be automatically restored.

In this embodiment, the control program 1 obtains a checksum value of the control program 14 on the control device 1 side, and supplies the obtained checksum value to the monitoring device 3.
4 shows an example of detecting an abnormality in the control program 1 stored in the flash ROM 13 from the monitoring device 3 side.
4 may be read to obtain a checksum value, and whether the control program 14 is normal or not may be determined from the obtained checksum value. Further, the control program 14 stored in the flash ROM 13 is sent from the monitoring device 3 side.
May be read and compared with the backup program to determine whether the control program 14 is normal.

[0053]

As described above, the electronic device according to the first aspect and the recording medium on which the ROM data monitoring program according to the sixth aspect is recorded, when the abnormality of the control program stored in the flash ROM is detected. Has a configuration to cut off the power supply to the controlled device,
Malfunction of the controlled device can be prevented.

The control device obtains a checksum value of the control program stored in the flash ROM,
By repeatedly performing the supply of the obtained checksum value to the monitoring device within a preset period, the monitoring device can accurately detect the abnormality of the control program.

The electronic device according to claim 3 and claim 6
When the recording medium storing the ROM data monitoring program according to the present invention detects an abnormality in the control program stored in the flash ROM, the power supply to the control target device is shut off and the storage medium is stored in the backup program storage unit. The control program stored in the flash ROM is restored by writing the backup program to the flash ROM, so if an error occurs in the control program stored in the flash ROM, the malfunction of the control target device will occur. And the control program can be automatically restored.

The control device obtains the checksum value of the control program stored in the flash ROM,
By repeatedly performing the supply of the obtained checksum value to the monitoring device within a preset period, the monitoring device can accurately detect the abnormality of the control program.

The monitoring device detects an abnormality in the control program stored in the flash ROM by comparing the control program stored in the flash ROM with the backup program stored in the backup program storage. With this configuration, an abnormality in the control program can be accurately detected. Since the control device does not need to obtain the checksum value of the control program stored in the flash ROM, the load on the control device is reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram of an electronic device according to the present invention.

FIG. 2 is a flowchart (part 1) showing a control program monitoring and recovery operation of the electronic device according to the present invention.

FIG. 3 is a flowchart (part 2) illustrating a control program monitoring and recovery operation of the electronic device according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 control device (control microcomputer) 2 backup program storage unit 3 monitoring device (monitoring microcomputer) 4 power supply / cutoff unit 5 controlled device 6 device power supply 7 microcomputer power supply 8 main power switch 9 control device power supply relay unit 10 bus 13 Flash ROM 14 Control program 21 Backup program storage area 22 Check result storage area

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G06F 12/16 320 G06F 1/00 334C

Claims (7)

[Claims] A control device for controlling an operation of the control target device based on a control program stored in a flash ROM; a power supply / cutoff unit for supplying / cutting power to the control target device; A monitoring device for detecting an abnormality in the control program stored in the ROM; and when the monitoring device detects an abnormality in the control program stored in the flash ROM, the power supply / cutoff unit is activated. An electronic device, wherein power supply to the control target device is cut off via the control unit. 2. The flash memory according to claim 2, wherein
The checksum value of the control program stored in the storage device is obtained, and the supply of the obtained checksum value to the monitoring device is repeatedly performed within a preset period, and the monitoring device sends the checksum value from the control device to the monitoring device. It is determined that there is an abnormality in the control program stored in the flash ROM based on the fact that the checksum value is not supplied within the set period and the change of the checksum value supplied from the control device. The electronic device according to claim 1, wherein: 3. A control device for controlling the operation of a controlled device based on a control program stored in a flash ROM; a power supply / cutoff unit for supplying / cutting power to the controlled device; A backup program storage unit for storing a backup program having the same contents as the control program stored in the ROM; and, when an abnormality of the control program stored in the flash ROM is detected, via the power supply / cutoff unit. A monitoring device that shuts off power supply to the controlled device and restores the control program stored in the flash ROM by writing the backup program stored in the backup program storage unit to the flash ROM. A telephone characterized by having Child equipment. 4. The flash ROM according to claim 1, wherein
The checksum value of the control program stored in the storage device is obtained, and the supply of the obtained checksum value to the monitoring device is repeatedly executed within a preset period. It is determined that there is an abnormality in the control program stored in the flash ROM based on the fact that the checksum value is not supplied within the set period and the change of the checksum value supplied from the monitoring device. The electronic device according to claim 3, wherein: 5. The monitoring device according to claim 1, wherein the monitoring device is a flash ROM.
4. An abnormality of the control program stored in the flash ROM is detected by comparing a control program stored in the flash program with a backup program stored in the backup program storage unit. Electronic device as described. 6. A control program monitoring means for detecting an abnormality in a control program stored in a flash ROM, and controlling based on the control program when an abnormality is detected in the control program. A recording medium storing a ROM data monitoring program, wherein a ROM data monitoring program for causing a computer to execute a power shutoff means for interrupting power supply to a control target device is recorded on a computer readable recording medium. 7. A control program monitoring means for detecting an abnormality in a control program stored in a flash ROM, and controlling based on the control program when an abnormality is detected in the control program. ROM for causing a computer to execute a power cutoff unit for cutting off power supply to a control target device, and a control program restoring unit for restoring the control program by writing a control program backed up in an EEPROM to the flash ROM. A recording medium storing a ROM data monitoring program, wherein the data monitoring program is recorded on a computer-readable recording medium.