KR20210070656A - Apparatus for back up user data file of plc and method of the same - Google Patents

Abstract

As a device that backs up user data files using a file system provided by a PLC's operating system, provided, in the present invention, is a PLC user data file backup device comprising: a file location registration part that registers a location of the user data file in the backup target file list when the user program is executed; a file change detection part that detects whether or not user data files have been changed by checking the list of files to be backed up; and a backup processing part that stores the user data file before the change in a backup file storage part when the user data file is changed. Therefore, the present invention is capable of having an effect of stably managing the backup files.

Description

Device and method for backing up user data file of PLC {APPARATUS FOR BACK UP USER DATA FILE OF PLC AND METHOD OF THE SAME}

The present invention relates to an apparatus and method for backing up a user data file of a PLC, and more particularly, an apparatus for automatically backing up user data to a file by detecting a change in user data in a file system provided by an operating system during idle time of a processor and methods.

PLC (Programmable Logic Controller) is a core equipment that manages and operates functions such as machine control, diagnosis and safety in an industrial environment.

In the conventional PLC, a function for backup was limited due to limitations of the operating system and computing power.

In addition, in the case of the conventional PLC, it is implemented to back up user data when the user requests, designates the user's desired time, or when the PLC is terminated, so it is backed up by unexpected operations (such as reset due to power failure or malfunction of the user program). In this case, there was a problem in that the user data was lost because it was terminated before the user data was completely backed up.

1 is a diagram for explaining a conventional user data file backup method.

Referring to FIG. 1 , in the conventional method of backing up user data, a backup request by a user in a Programmable And Debugging Tool (PADT) (or Human Machine Interface) 2 or a backup request due to abnormal termination such as a power outage , or when PLC(1) is abnormally terminated, user data such as operation information and environment variable setting information stored in the memory (3) inside the PLC(1) is saved to the internal storage device (4) of the PADT (or HMI)(2). It was backed up as an image, not a file.

In the case of such a conventional user data backup method, when the operation of the PLC 1 is stopped by an external environment (power failure or malfunction of the user program, etc.), the power of the PLC 1 is turned off before the backup is completely completed and the user data may be lost.

In preparation for such a case, a method of increasing the backup success rate by using a supercapacitor or the like to maintain the backup time for a long time has been used. However, recently, as the size of user data increases and the amount of power consumed by the CPU increases, the time required for the backup becomes longer and the above method is not a complete solution.

An object of the present invention is to provide a user data file backup device of a PLC that automatically backs up user data to a file by detecting a change in user data in a file system provided by an operating system during idle time of a processor.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned above can be clearly understood by those of ordinary skill in the art to which the present invention belongs from the description below. There will be.

In order to solve this problem, the present invention is a device for backing up a user data file using a file system provided by an operating system of a PLC, and a file location that registers the location of the user data file in the backup target file list when the user program is executed PLC comprising a register, a file change detection unit that detects whether a user data file is changed by checking a list of files to be backed up, and a backup processing unit that stores the user data file before the change in a backup file storage unit when the user data file is changed Provides a backup device for user data files.

Here, the file change detection unit may detect whether the user data file is changed during idle time of the processor using a scheduler of the operating system.

Also, the backup processing unit may store the user data file before the change in idle time of the processor using a scheduler of the operating system.

In addition, the file change detection unit may determine that the user data file is changed when the time stamp of the user data file is changed.

Also, the file location registration unit may register the absolute path of the user data file in the backup target file list.

In addition, the backup processing unit may synchronize the user data file before the change with the external storage device or copy it to the external storage device.

A method of backing up user data files using a file system provided by an operating system of a PLC, comprising:

In addition, the present invention includes the steps of registering the location of the user data file in the backup target file list when executing the user program, checking whether the processor is idle time using the scheduler of the operating system, and checking the idle time of the processor A method of backing up user data files in PLC, including detecting whether the user data file has been changed by checking the backup target file list, and storing the user data file before the change in the backup file storage unit when the user data file is changed. to provide.

According to the present invention, a change in user data is detected in the file system provided by the operating system during the idle time of the processor, and the user data is automatically backed up to a file, thereby minimizing the backup time and stably managing the backup file. It works.

Effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those of ordinary skill in the art from the following description.

1 is a diagram for explaining a conventional user data file backup method.
2 is a schematic block diagram of a user data file backup apparatus of a PLC according to an embodiment of the present invention.
3 is a diagram for explaining a user data file backup method of a PLC according to an embodiment of the present invention.
4 is a flowchart of a user data file backup method of a PLC according to an embodiment of the present invention.

The terms or words used in the present specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and the inventor may properly define the concept of the term in order to best describe his invention. It should be interpreted as meaning and concept consistent with the technical idea of the present invention based on the principle that there is.

Accordingly, the embodiments described in this specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention and do not represent all the technical spirit of the present invention, so various equivalents that can be substituted for them at the time of the present application It should be understood that there may be variations and examples.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art can easily implement them.

PLC (Programmable Logic Controller) replaces the conventional functions of relays, timers and counters in the control panel with semiconductor devices such as large-scale integrated circuits and transistors. It is a control device with high autonomy.

The National Electrical Manufacturers Association (NEMA) defines a PLC as “using a programmable memory to perform special functions such as logic, sequencing, timing, counting, and arithmetic through digital or analog input/output modules, It is defined as "a digitally operated electronic device that controls a processor".

The application range of PLC is gradually expanding according to the demand for automation and high efficiency of equipment. In particular, the PLC's demands following factory automation and FMS (Flexible Manufacturing System) are being applied from small-scale machine tools to large-scale system facilities with the current trend of high-functionality and high-speed, from the effect of replacing medium-sized or larger relay control panels in the past.

With the recent development of the operating system and the increase in the computing power of the CPU, the idle time of the processor of the PLC is also increasing. Accordingly, the present invention automatically backs up user data to a file by detecting a change in user data in the file system provided by the operating system during idle time of the processor using the scheduler of the operating system, even if the user does not specify a backup time separately. By doing this, we propose a method to minimize the backup time and manage the backup file stably.

Here, when the operating system is Linux, the present invention can be implemented more effectively and stably by using the open source cron daemon and the rsync function, and in the case of an operating system other than Linux, it can be implemented as a system program (C code) .

2 is a schematic block diagram of a user data file backup apparatus of a PLC according to an embodiment of the present invention.

The user data file backup apparatus 100 of the PLC according to the embodiment of the present invention is characterized in that it backs up the user data file using a file system provided by the operating system of the PLC.

As shown in FIG. 2 , the PLC user data file backup device 100 according to an embodiment of the present invention includes a file location registration unit 110 , a file change detection unit 120 , and a backup processing unit 130 . can be And, each of these components may be implemented using a file system provided by the operating system.

The file location registration unit 110 registers the location of the user data file in the backup target file list when the user program 10 is executed.

Here, the user program means a program that controls the PLC, and is created by the user. PLC does not have contacts or coils such as relay sequences, and the operation of connecting contacts or coils is handled in software by a user program. That is, the user program is stored in the memory of the PLC, and the PLC sequentially reads the stored user program and operates according to the contents.

In addition, the user data may include driving information and environment variable setting information. In addition, the user data file means a dump file of memory data used in a user program, which means data stored as a file, not simply data stored in a memory area.

These PLC modes include a program mode for creating a user program, a run mode for actually executing the program written by the user, a pause mode for temporarily stopping the execution of the user program, and a debug mode for the user to debug the program. there is That is, after the user writes a program through the peripheral device in the program mode, and then switches to the run mode, the PLC receives an external input from the input unit, performs an operation according to the program written by the user, and stores the result in the data area. The data to be output to the outside is output through the output unit.

The file location registration unit 110 may register the absolute path of the user data file in the backup target file list. Here, the absolute path means a path of a specified file starting from the root of the file system.

The file change detection unit 120 detects whether the user data file is changed by the user program by checking the backup target file list.

Here, the file change detection unit 120 may detect whether the user data file is changed during idle time of the processor using the scheduler 20 of the operating system. Alternatively, it is also possible to detect whether the user data file is changed periodically at a time specified by the user.

The file change detection unit 120 may determine that the user data file has been changed when the time stamp (file creation or modification time) of the user data file is changed.

For example, if your operating system is Linux, you can use the find command to detect changes in user data files. An example using the find command is as follows.

<Example 1>

root@uz3eg_iocc_2019_1:~# touch a b → Create file a and file b

root@uz3eg_iocc_2019_1:~# find . -newer a → Find files with a newer change time than file a in the file list (file a and file b are not displayed because they were created at the same time)

root@uz3eg_iocc_2019_1:~# touch b → change b file time

root@uz3eg_iocc_2019_1:~# find . -newer a → Find files with a newer change time than file a in the file list (b is displayed)

./b

When the user data file is changed, the backup processing unit 130 stores the user data file before the change in the backup file storage unit 30 .

The backup processing unit 130 may use the scheduler 20 of the operating system to store the user data file before the change in the idle time of the processor. Alternatively, the user data file may be periodically stored at a time specified by the user.

The backup processing unit 130 may synchronize the user data file before the change with the external storage device or copy it to the external storage device.

3 is a diagram for explaining a user data file backup method of a PLC according to an embodiment of the present invention.

Referring to FIG. 3 , the user data file backup method of the PLC according to the embodiment of the present invention automatically stores the user data file in the PLC side external storage device 210 and the external network storage device 220 during the idle time of the processor. can be backed up.

Here, if the operating system is Linux, the backup can be performed using the rsync command. An example using the rsync command is as follows.

<Example 2>

root@uz3eg_iocc_2019_1:~# mkdir /home/backup → Create /home/backup directory

root@uz3eg_iocc_2019_1:~# ls -l /home/backup → /home/backup directory file information output (check that the file does not exist)

total 0

root@uz3eg_iocc_2019_1:~# ls -l → Display current directory file information

total 0

-rw-r--r-- 1 root root 0 Aug 19 00:39 a

-rw-r--r-- 1 root root 0 Aug 19 00:39 b

root@uz3eg_iocc_2019_1:~# rsync -azvh * /home/backup → Sync the current directory to the /home/backup directory

root@uz3eg_iocc_2019_1:~# ls -l /home/backup → /home/backup directory file information output (confirm that it is synchronized with the current directory)

total 0

-rw-r--r-- 1 root root 0 Aug 19 00:39 a

-rw-r--r-- 1 root root 0 Aug 19 00:39 b

root@uz3eg_iocc_2019_1:~# touch b → change b file to the latest time

root@uz3eg_iocc_2019_1:~# ls -l → Output current directory file information (check b file time change)

total 0

-rw-r--r-- 1 root root 0 Aug 19 00:39 a

-rw-r--r-- 1 root root 0 Aug 19 00:46 b

root@uz3eg_iocc_2019_1:~# rsync -azvh * /home/backup → Sync the current directory to the /home/backup directory

sending incremental file list

b

sent 95 bytes received 35 bytes 260.00 bytes/sec

total size is 0 speedup is 0.00

root@uz3eg_iocc_2019_1:~# ls -l /home/backup → Check that only b is synchronized

total 0

-rw-r--r-- 1 root root 0 Aug 19 00:39 a

-rw-r--r-- 1 root root 0 Aug 19 00:46 b

In addition, when the programmable and debugging tool (PADT) (or human machine interface (HMI)) (2) requests a backup by the user or a backup request due to abnormal termination such as power failure, or the PLC (1) is abnormally terminated In this case, the user data stored in the internal memory 3 of the PLC 1 may be backed up in the form of an image rather than a file in the internal storage 4 of the PADT (or HMI) 2 .

The PLC user data file backup method according to the embodiment of the present invention can be implemented as an automatic backup program using the cron daemon when the operating system is Linux, and in the case of other operating systems, the aforementioned find, rsync, cron daemons, etc. Since all of these commands are implemented as open source, it can be similarly written as a C code program.

4 is a flowchart of a user data file backup method of a PLC according to an embodiment of the present invention.

The PLC user data file backup method according to an embodiment of the present invention includes a backup file list registration step (S10), a process idle time check step (S20), a user data file change check step (S30), and a user data file backup step ( S40) may be included.

First, when the user program 10 is executed, the location of the user data file is registered in the backup target file list (S10). In this case, the location of the user data file may include an absolute path of the user data file.

Next, it is checked whether the processor is idle using the scheduler 20 of the operating system (S20).

Next, if it is confirmed as the idle time of the processor, it is checked whether the user data file is changed by the user program by checking the backup target file list (S30). At this time, if the time stamp (creation or modification time of the file) of the user data file is changed, it may be determined that the user data file is changed.

Next, when the user data file is changed, the user data file before the change is stored in the backup file storage unit 30 (S40). In this case, the user data file before the change may be synchronized with the external storage device or copied to the external storage device.

As such, in the method for backing up user data files of PLC according to an embodiment of the present invention, the user data files are periodically backed up during the idle time of the processor, which is a component of the PLC, and an external storage device or an external storage device that is a component of the PLC. By periodically updating the network storage location with the latest user data files, you can perform fast and reliable backups.

On the other hand, when a CPU with insufficient computing power is used, a command to configure a user program for backup is provided so that the user can decide whether to use the corresponding function, thereby leading to the same effect.

The above detailed description is illustrative of the present invention. Further, the foregoing is merely illustrative of preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, changes or modifications are possible within the scope of the concept of the invention disclosed herein, the scope equivalent to the written disclosure, and/or within the scope of skill or knowledge in the art. The above-described embodiments are for illustrating the best state for carrying out the present invention, and the implementation in other states known in the art for using other inventions such as the present invention, and the specific application fields and uses of the present invention. Various changes are also possible. Accordingly, the detailed description of the present invention is not intended to limit the present invention to the disclosed embodiments. Also, the appended claims should be construed as including other embodiments.

10: User program
20: Scheduler
30: backup file storage
110: file location register
120: file change detection unit
130: backup processing unit

Claims (7)

A device that backs up user data files using the file system provided by the PLC's operating system.
a file location registration unit that registers the location of the user data file in the backup target file list when the user program is executed;
a file change detection unit for detecting whether the user data file has been changed by checking the backup target file list; and
a backup processing unit for storing the user data file before the change in a backup file storage unit when the user data file is changed;
PLC user data file backup device including
The method of claim 1,
The file change detection unit
Detecting whether the user data file is changed during idle time of the processor using the scheduler of the operating system
User data file backup device in PLC.
The method of claim 1,
The backup processing unit
Using the scheduler of the operating system to store the user data file before the change in the idle time of the processor
User data file backup device in PLC.
The method of claim 1,
The file change detection unit
When the timestamp of the user data file is changed, it is determined that the user data file is changed.
User data file backup device in PLC.
The method of claim 1,
The file location register
Registering the absolute path of the user data file in the backup target file list
User data file backup device in PLC.
The method of claim 1,
The backup processing unit
Synchronizing the user data file before the change with an external storage device or copying it to the external storage device
User data file backup device in PLC.
A method of backing up user data files using a file system provided by an operating system of a PLC, comprising:
registering the location of the user data file in the backup target file list when the user program is executed;
checking whether the processor is idle using a scheduler of the operating system;
detecting whether the user data file has been changed by checking the backup target file list when it is confirmed as the idle time of the processor; and
When the user data file is changed, storing the user data file before the change in a backup file storage unit
PLC user data file backup method including.

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