JP3451489B2 - RAM content destruction handling method and programmable controller - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a RAM content destruction handling method and a programmable controller adapted to this method.

[0002]

2. Description of the Related Art In a programmable controller or the like, a RAM having good response and capable of high-speed processing is used as a storage location for user programs and other data.

As shown in FIG. 5, the programmable controller 1 includes an MPU 2, a ROM 39, a RAM 4, an interface 6 with a peripheral tool 5, and an external input / output device 7.
And an interface 8 with a bus are connected by a bus.

As shown in FIG. 6, the ROM 39 is assigned a system program area, and the RAM 4 is assigned a user program area, a system setting data area, a data setting data area, an I / O memory area, and a work memory area. In MPU2, ROM
The system program of 39 allows the control operation by exchanging data with the peripheral tool 5 and the external input / output device 7 while using the user program of the RAM 4 and the like.

However, since the contents of the RAM are destroyed when a power failure occurs due to consumption of the backup power source or the like, a separate readable / writable nonvolatile memory is provided and the same data is stored in this nonvolatile memory. Furthermore, it is known to check whether the contents of the non-volatile memory have been destroyed during a power failure.

For example, in Japanese Patent Laid-Open No. 54-107226, a check word is created using normal data immediately after a power failure, and a check word is created using the same contents in a non-volatile memory after power failure recovery. There is disclosed a technique for preventing troubles such as malfunctions by processing when the contents of the nonvolatile memory are destroyed when these checkwords do not match.

In recent years, high-quality non-volatile memories such as flash memories have become widespread, and the trouble of destroying the contents of the non-volatile memory has been reduced. On the other hand, however, the problem that the contents of RAM are destroyed at the time of power failure still remains. There is.

[0008]

Therefore, in a programmable controller, etc.
Destruction of the contents of the AM occurs at an unexpected time, and if the power is turned on without noticing it, abnormal operation may occur and a fatal malfunction may occur.

A battery has been conventionally used as a backup power source, but a highly reliable battery used for backup has a high cost and a RAM.
It is also necessary to replace the battery periodically to prevent the contents from being destroyed. Therefore, it is desirable to use a capacitor that is low in cost and does not require maintenance, but since the capacitor discharges in a relatively short time, the power is turned on and abnormal operation is performed without noticing the destruction of the RAM contents. The probability of doing
Will be higher than the battery.

The present invention solves the above-mentioned problems, and when the RAM content is destroyed due to insufficient capacity of the backup power source, etc., it is detected and the RAM content is restored using the data stored in the non-volatile memory. Or RAM to the user
Provided are a RAM content destruction handling processing method and a programmable controller for notifying malfunction of contents and preventing malfunction.

[0011]

In order to achieve the above object, the method of the invention according to claim 1 of the present invention comprises:
RAM content inspection data comparison / inspection step for comparing the RAM content inspection data written in the nonvolatile memory with the RAM content inspection data written in the RAM, and the RAM content inspection data comparison inspection In the step
When the RAM content inspection data written in the non-volatile memory and the RAM content inspection data written in the RAM do not match, a destruction notification step of notifying the user of the RAM content destruction and the RAM content inspection data comparison Inspection
RA written in the non-volatile memory in step
Non-volatile memory for copying RAM content inspection data, user program and system setting data written in the non-volatile memory when the M content inspection data does not match the RAM content inspection data written in the RAM Copying step and the data for RAM content inspection
Write to non-volatile memory in the data comparison inspection step
RAM content inspection data and R written in RAM
When it matches with the AM content inspection data, or
After switching from gramming mode to operation mode,
User program and system written in the memory
System setting data and the user program written in RAM.
Users comparing gram and system configuration data
Data comparison inspection step for program / system settings
And the above user program / system setting data comparison
Written to non-volatile memory during the inspection step
User program, system setting data, and RAM
User program written, system setting data
When does not match, the user program written in RAM
Program and system setting data to non-volatile memory.
And a RAM copying step for performing the same.

Further, the invention method of claim 2 of the present invention is
RAM content inspection data comparison inspection that compares the RAM content inspection data written in the nonvolatile memory with the RAM content inspection data written in the RAM when the power is turned on.
Step and the RAM content inspection data comparison inspection step described above.
In-up, when the RAM contents inspection data written in the RAM contents inspection data and RAM written in the nonvolatile memory does not match, the destruction notification step of notifying the RAM contents disruption to the user, the RAM contents For inspection
In the data comparison / inspection step , when the RAM content inspection data written in the nonvolatile memory and the RAM content inspection data written in the RAM do not match, the RAM content inspection data written in the nonvolatile memory, the user program And a non-volatile memory copying step of copying the system setting data to the RAM, and the RAM.
Content inspection data RAM Content inspection data and RAM written in the nonvolatile memory in the comparison inspection step
When the data for RAM content inspection written in does not match, the abnormality correspondence setting judgment step for judging whether the setting of the abnormality correspondence setting means is abnormal stop setting or continuation setting,
In the above-mentioned abnormality handling setting determination step, when it is determined that the abnormal stop setting, an abnormal stop step of stopping the process ,
In the data comparison inspection step for RAM content inspection
RAM content inspection data written in non-volatile memory
And the RAM content inspection data written in the RAM
Operation mode or from the programming mode.
After switching to the hard disk, the unit written to the non-volatile memory
User program and system setting data, and RAM
For user programs and system settings written in
For user program and system setting to compare with data
Data comparison inspection step and the user program
In the system setting data comparison inspection step, non-volatile
User programs and system settings written in the local memory
Regular data and user program written in RAM
RAM when the system and system setting data do not match
The user program and system setting data written in
RAM copying step to copy data to non-volatile memory
When the abnormal stop step is not performed, the subsequent processing can be continued.

According to the invention of claim 3, the contents of the RAM are destroyed.
Inspection data area, user program area and system
A non-volatile memory having a system setting data area,
RA corresponding to each of the areas of the nonvolatile memory
M content Destruction inspection data area, user program area
RAM with data area for system and system settings
And, and writes to the non-volatile memory when the power is turned on.
RAM content inspection data and R written in RAM
Compare with AM content inspection data and write to non-volatile memory
Write in the RAM content inspection data and the RAM
If the RAM content inspection data is not matched,
Notify the user that the RAM contents have been destroyed and write it to the non-volatile memory.
Written RAM content inspection data, user program
Copy the system and system setting data to RAM and
However, the RAM content inspection data written in the non-volatile memory
Data and RAM content inspection data written in RAM
Match, or from programming mode
After the mode is switched to the
User program and system setting data, and R
User programs and system settings written in AM
Compared with the regular data and written in the non-volatile memory
User program, system setting data, and RAM
User program written, system setting data
If and do not match, the user program written in RAM is
Program and system setting data to non-volatile memory.
Peeing.

[0014]

[0015]

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.
A description will be given with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention.

Since FIG. 1 has substantially the same configuration as the conventional programmable controller shown in FIG. 5, the same elements as those in FIG. 5 are designated by the same reference numerals, and the description thereof will be omitted.
3 is a flash memory (readable and writable non-volatile memory).

The flash memory 3 stores a system program 30 as shown in FIG.
The RAM includes a RAM content destruction inspection data area 31 for writing data for destructive inspection, a user program area 32 for writing a user program, and a system setting data area 33 for writing system setting data. In the content destructive inspection data area 31, for example, RAM content destructive inspection data as shown in FIG. 3 is stored.

In the RAM 4, the RAM content destruction inspection data area 41, the user program area 42, the system setting data area 43, and the data setting data area 44 corresponding to the respective areas of the flash memory 3 are provided. The RAM 4 has an I / O memory area 45, a work memory area 46, and a destruction notification flag area 47. The RAM 4 includes a user program area 42, a system setting data area 43, a data setting data area 44, and an I / O memory area 45. The user can write the respective data and the like as necessary.

A capacitor 9 is provided as a backup power source for the RAM 4, and the capacitor 9 keeps R while the programmable controller is powered off.
Back up so that the contents of AM4 do not change (do not destroy).

The contents of the RAM content destructive inspection data area 31 of the flash memory 3 are copied to the RAM content destructive inspection data area 41 of the RAM 4 to be stored in the RAM.
Used for content destructive inspection. That is, the power source O for a long time
When the capacitor 9 is discharged by the FF or the like, the backup may not be effective and the contents of the RAM 4 may be destroyed. However, if the contents of the RAM 4 are destroyed, R may occur.
The RAM content destruction inspection data (4) of AM4 also changes (destroys). The programmable controller uses the RAM of the flash memory 3 each time the power is turned on.
The content destructive inspection data (31) is compared with the RAM content destructive inspection data (41) of the RAM 4, and when the RAM content destructive occurs, as described above, RA
Since the RAM content destruction inspection data (41) of M4 is destroyed, the comparison result becomes inconsistent, and the RAM content destruction can be detected.

User program area 4 of RAM 4
2 and the contents of the system setting data area 43 are respectively copied to the user program area 32 and the system setting data area 33 of the flash memory 3 and used as a backup.

When the RAM contents are destroyed and the RAM contents destruction inspection data (31) of the flash memory and the RAM contents destruction inspection data (41) of the RAM do not match, processing is performed without malfunction in response to this. There are two cases to proceed.

One is a case where a malfunction occurs unless the user restarts the operation after abnormally stopping and resetting the data setting data (44) and the I / O memory (45). One of them is the case where there is no problem even if the operation is restarted without the need for resetting the data setting data (44) and the I / O memory (45).

Which of these two cases is determined by the usage status of the programmable controller 1, the user program to be used, etc., so that the user can select and set either one depending on the situation. Become.
In order to make this setting, abnormality handling setting means is provided. That is, in this embodiment, for example, in the system setting data area 43 shown in FIG. 3, "abnormal stop" is provided as an abnormality handling setting means for setting either abnormal stop or continuing processing. Areas are provided for "0000" for (memory abnormality) and "0001" for "continue (no memory abnormality)".

The flow of the RAM content destruction handling process of the programmable controller 1 configured as described above will be described below with reference to FIG.

FIG. 4 is a flow chart showing an embodiment of the RAM content destruction handling method of the present invention. The user program is executed immediately after the programmable controller 1 is turned on or in the programming mode. The flow immediately after writing the data for system setting to the RAM 4 is shown.

[Flow in Manufacturing Process] In the manufacturing process, the system program 30 is stored in the flash memory 3.
And RAM content inspection data (31) are written.
Further, the abnormality handling setting means in the system setting data (43) is set to "0001 (no memory abnormality)".

In the final operation check of the manufacturing process, when the power is turned on (step 401), the RAM content inspection data (31) of the flash memory 3 and RA of the RAM 4 are checked.
The M content inspection data (41) is compared (comparative inspection step 402). At this stage, the RAM content inspection data (41) of the RAM 4 has not been set, so a mismatch (NO) occurs, the RAM 4 is cleared in step 405, and the RAM destruction notification flag (47) is set in the destruction notification step 406. Set and notify the user of RAM content destruction. Further, in the non-volatile memory copying step 407, the RAM content inspection data (31) of the flash memory 3, the content of the user program area 32, and the content of the system setting data area 33 are copied to the corresponding areas of the RAM 4. At this stage, both the user program area 32 and the system setting data area 33 are empty. The RAM content inspection data (41) written in the RAM 4 is used later in step 402.

The destruction notifying step 406 and the non-volatile memory copying step 407 can be reversed in order.

Next, an abnormality handling setting judgment step 408
Then, since the abnormality handling setting means is set to "0001 (no memory abnormality)" (continuation setting), it becomes (NO), and the process continues in step 410. In this manufacturing process, the user program areas 32 and 42 of both the flash memory 3 and the RAM 4 are further added before shipment.
System setting data areas 33, 43, RAM 4 data setting data area 44, I / O memory area 4
5. Clear all destruction notification flag areas 47.

[Flow in Use] When the user turns on the power (step 401), the RAM content inspection data (31) of the flash memory 3 is compared with the RAM content inspection data (41) of the RAM 4 (41). Comparative inspection step 402). If it is not in the state of RAM destruction, it becomes (YES) in the comparative inspection step 402, and step 4
Move to 03. In step 403, the flash memory 3
User program area 32, system setting data area 33 and RAM 4 user program area 42,
The system setting data area 43 is compared. When the power is turned on for the first time, both are cleared and the result is "match (YES)". Immediately, the process can be continued at step 410 and the subsequent process can be continued.

Here, the user switches to the programming mode and writes the user program and system setting data in the RAM 4. Next, the user switches from programming mode to operating mode. When switching from programming mode to operation mode, MPU2
The process starts from (A) of FIG. That is, first,
In step 403, the user program area 32 and the system setting data area 33 of the flash memory 3 are both cleared, and the user program area 42 and the system setting data area 43 of the RAM 4 are set by the user for the user program and the system setting. Since the data has been written, the result is "mismatch (NO)" and step 40
4 to execute the user program (42) in the RAM 4,
After writing the system setting data (43) to the flash memory 3 to back it up, the process can be continued at step 410 and the subsequent process can be continued.

By backing up the user program (42) and the system setting data (43) to the flash memory 3, the power supply capacity of the capacitor 9 is lost due to long-term non-use and other reasons, and the RAM contents are destroyed. In this case, the user program (42) and the system setting data (43) can be restored.

When the power is turned on for the second time and thereafter, the RAM 4
If the contents of RAM are not destroyed, the RAM content inspection data, the user program, and the system setting data are the same in the flash memory 3 and the RAM 4, so step 401, comparison inspection step 402 (YE
S), step 403 (YES), and step 410, and the subsequent processing can be continued.

If the contents of RAM 4 are destroyed, RAM
Since the RAM content inspection data (41) of No. 4 is also destroyed, in the comparison inspection step 402, “mismatch (N
O) ”and clears the RAM in step 405,
In the destruction notification step 406, the RAM destruction notification flag (4
7) is set to notify the user that the RAM contents are corrupted. In addition, the non-volatile memory copying step 40
At 7, the RAM content inspection data (31) of the flash memory 3, the user program (32), and the system setting data (33) are copied to the corresponding areas of the RAM 4, and the RAM content inspection data (41) of the RAM 4 is copied. , User program (42), system setting data (43)
To be revived.

The destruction notifying step 406 and the non-volatile memory copying step 407 can be reversed in order.

Next, the abnormality handling setting judgment step 408
Then, if the abnormality handling setting means is "0001 (no memory abnormality)" (continuous setting), it becomes (NO),
The process can be continued at step 410 and the subsequent processes can be continued. The abnormality response setting means is "0000
If (memory abnormal) is set (abnormal stop setting), the determination is YES, and the process moves to the abnormal stop step 409 to stop the process.

The setting of the abnormality handling setting means is set to (abnormal stop setting) in a normal use state, and the user starts the operation after resetting the data in the data setting memory and the I / O memory. . If the data in the data setting memory or the I / O memory does not need to have the value when the power was turned off last time when the operation is started, it can be set to (continuous setting).

If the user switches to the programming mode while the programmable controller 1 is in use, rewrites the user program 42 and the system setting data 43, and ends the processing as it is, R is turned on at the next power-on.
Even if the AM4 is not destroyed, the user program (42) and system setting data (43) in the RAM4 and the user program (32) and system setting data (33) in the flash memory 3 do not match. In this case, step 403 becomes (NO) and step 404
To update the flash memory 3 and the subsequent RAM
In preparation for the destruction of No. 4, it is possible to move to step 410 and continue the subsequent processing.

The RAM destruction notification to the user is given immediately when the destruction notification step 406 is executed, or immediately before the abnormal stop step 409 or the process continuation step 410, or the usage status of the programmable controller or the control system is notified. Correspondingly, destruction notification flag (47)
May be referred to by the user program and notified.

[0043]

As can be understood from the above description, according to the present invention, the RAM content inspection data is stored in the nonvolatile memory and the RAM, and when the power is turned on,
Non-volatile memory RAM content inspection data and RAM R
If the RAM is destroyed and becomes inconsistent by comparing and collating with the AM content inspection data, the RAM of the nonvolatile memory
Since the contents inspection data, the user program, and the system setting data are written in the RAM and restored to notify the user of the destruction of the RAM contents, abnormal start of operation can be avoided.

Furthermore, if the RAM is destroyed and the discrepancies occur, the process is stopped and the corresponding action is taken, or if the action is not required, the process can be continued as it is. It is possible to take measures without waste to avoid starting operation.

Further, the RAM content destruction inspection data area, the user program area, and the system setting data area are provided in both the non-volatile memory and the RAM, and common data and the like are provided in these areas, whereby the RAM Even if the backup power is consumed and the RAM contents are destroyed, this is detected to notify the user of the RAM contents destruction, and the user program and system setting data are copied from the non-volatile memory to the RAM to recover. be able to.

If a capacitor is used as a backup power source for RAM, the cost can be reduced compared to a battery,
There is no need to replace the battery.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating contents of a RAM and a nonvolatile memory in FIG.

FIG. 3 is an explanatory diagram illustrating contents of a RAM and a nonvolatile memory in FIG.

4 is an R of the programmable controller in FIG.
The flowchart which shows the AM content destruction corresponding process.

FIG. 5 is a block diagram showing a conventional programmable controller.

FIG. 6 is an explanatory diagram illustrating contents of a RAM and a nonvolatile memory in FIG.

[Explanation of symbols]

1 Programmable controller 3 Flash memory (nonvolatile memory) 4 RAM 9 Capacitor (backup power supply) 31 RAM data destruction inspection data area (in flash memory) 32 User program area (in flash memory) 33 System setting data area (flash memory 41) RAM content destructive inspection data area (in RAM) 42 user program area (in RAM) 43 system setting data area (in RAM) 44 data setting data area 402 comparative inspection step 406 destruction notification step 407 non-volatile memory Copying step 408 Abnormal response setting determination step 409 Abnormal stop step

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Sasaki 10 Ouron Co., Ltd., Hanazono Todo-cho, Ukyo-ku, Kyoto City, Kyoto Prefecture (56) References JP-A-1-136201 (JP, A) JP-A-2- 19902 (JP, A) JP-A-2-278411 (JP, A) JP-A-1-175001 (JP, A) JP-A-2-300836 (JP, A) Actual development Sho-56-113902 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G05B 19/04-19/05 G05B 9/02

Claims (3)

(57) [Claims] 1. Writing to a non-volatile memory at power-on
RAM content inspection data and written in RAM
Compare with RAM content inspection dataFor RAM content inspection
Data comparison inspection stepWhen, the aboveRAM content inspection data comparison inspection stepsmell
The RAM content inspection data written in the non-volatile memory.
Data and RAM content inspection data written in RAM
If the two do not match, notify the user of RAM contents destruction
Destruction notification step, the aboveRAM content inspection data comparison inspection stepsmell
The RAM content inspection data written in the non-volatile memory.
Data and RAM content inspection data written in RAM
RA written in the non-volatile memory when the values do not match
M content inspection data, user program and system
Non-volatile memory copy that copies setting data to RAM
Steps,In the data comparison inspection step for RAM content inspection
RAM content inspection data written in non-volatile memory
And the RAM content inspection data written in the RAM
Operation mode or from the programming mode.
After switching to the hard disk, the unit written to the non-volatile memory
User program and system setting data, and RAM
For user programs and system settings written in
For user program and system setting to compare with data
Data comparison inspection step, Data comparison inspection for the above user programs and system settings
In the step, the user written in the non-volatile memory
Write the program, system setting data and RAM
The embedded user program and system setting data
When they do not match, the user program written in RAM
System, copy system setting data to non-volatile memory
RAM copy step, R characterized by having
AM content destruction handling method. 2. Writing to a non-volatile memory when the power is turned on
RAM content inspection data and written in RAM
Compare with RAM content inspection dataFor RAM content inspection
Data comparison inspection stepWhen, the aboveRAM content inspection data comparison inspection stepsmell
The RAM content inspection data written in the non-volatile memory.
Data and RAM content inspection data written in RAM
If the two do not match, notify the user of RAM contents destruction
Destruction notification step, the aboveRAM content inspection data comparison inspection stepsmell
The RAM content inspection data written in the non-volatile memory.
Data and RAM content inspection data written in RAM
RA written in the non-volatile memory when the values do not match
M content inspection data, user program and system
Non-volatile memory copy that copies setting data to RAM
Steps, the aboveRAM content inspection data comparison inspection stepsmell
The RAM content inspection data written in the non-volatile memory.
Data and RAM content inspection data written in RAM
If the values do not match, the setting of the abnormality response setting means stops abnormally.
Abnormal response setting judgment to judge either setting or continuous setting
Steps, Abnormal stop setting is made in the above abnormality handling setting judgment step.
When it is determined that the abnormal stop step to stop the process, In the data comparison inspection step for RAM content inspection
RAM content inspection data written in non-volatile memory
And the RAM content inspection data written in the RAM
Operation mode or from the programming mode.
After switching to the hard disk, the unit written to the non-volatile memory
User program and system setting data, and RAM
For user programs and system settings written in
For user program and system setting to compare with data
Data comparison inspection step, Data comparison inspection for the above user programs and system settings
In the step, the user written in the non-volatile memory
Write the program, system setting data and RAM
The embedded user program and system setting data
When they do not match, the user program written in RAM
System, copy system setting data to non-volatile memory
RAM copy step, Have If you do not go through the above abnormal stop steps, perform the subsequent processing.
RAM content destruction characterized by being able to continue
Corresponding processing method. 3. A data area for RAM content destruction inspection,
User program area and system setting data area
And a RA corresponding to each of the areas of the nonvolatile memory.
M content Destruction inspection data area, user program area
RAM with data area for system and system settings
And in the RAM written in the nonvolatile memory when the power is turned on.
Inspection data and RAM contents written in RAM
RAM content inspection data written in the non-volatile memory by comparing the
And the RAM content inspection data written in the RAM
If not, notify the user of RAM contents destruction.
The RAM content inspection data written in the non-volatile memory.
Data, user programs and system setting data
For inspecting the contents of RAM that was copied to RAM while being written to non-volatile memory
Data and RAM content inspection data written in RAM
If matches or from programming mode
Write to non-volatile memory after switching to operation mode
User program and system setting data
User program and system written in RAM
It is compared with the setting data and written in the non-volatile memory.
User program, system setting data, RAM
The user program and system setting data written in
User written in RAM when the data does not match
Program and system setting data in non-volatile memory
A programmable controller characterized by copying
Troller.