JP5039428B2 - Programmable controller and PLC system - Google Patents

Description

The present invention relates to a programmable controller, and more particularly, the operation mode to repeatedly execute a control program to be executed, and a programmable controller capable of switching the non-operational mode to stop execution of the execution target of the control program relates PLC system including a programming support device and programmable controller to create a program for a programmable controller.

  A programmable controller (hereinafter abbreviated as PLC) is a sequence control device widely used in FA (Factory Automation) control systems, and operates according to a dedicated program called a ladder program. Therefore, a desired sequence control device can be realized by rewriting the ladder program in the PLC. This ladder program is usually created using a program creation support apparatus in which a dedicated program is installed in a personal computer, and transferred (uploaded) to the PLC via a communication cable.

  If the ladder program uploaded in this way contains an error, the PLC cannot operate normally, so it is necessary to check the error of the ladder program in advance. Normally, an error check is performed in the program creation support apparatus before uploading the ladder program, but there is also a simple error check in the PLC after uploading the ladder program.

  Generally, the PLC has an operation mode in which a ladder program is executed (so-called RUN mode) and a non-operation mode in which a ladder program is not executed (so-called PROGRAM mode), and both modes are switched by a user operation. The error check in the PLC is meaningless unless it is executed before the ladder program is executed, that is, in the non-operation mode. Therefore, in the conventional PLC performing the error check, the upload of the ladder program is in the non-operation mode. The error check is performed before switching to the operation mode. If an error is found as a result of this error check, a warning message is output and the ladder program is deleted so that it is not executed by mistake.

  However, there are some control systems that are greatly affected by the suspension and resumption of the system and are not allowed to frequently switch the PLC to the non-operational mode. For such a control system, some PLCs can upload ladder programs even in the operation mode. However, since such a PLC is in the operation mode, an error check cannot be performed on the uploaded ladder program, and if a program including an error is uploaded, the PLC does not operate normally.

  That is, the ladder program uploaded in the non-operation mode can be checked for errors in the PLC, but the ladder program uploaded in the operation mode cannot be checked for errors in the PLC. Therefore, when uploading the ladder program during the operation mode, it is necessary to perform sufficient error checking in the program creation support apparatus.

  In addition, with the recent increase in speed and functionality of PLCs, ladder programs have become large and complex, and there are increasing cases in which a single ladder program is jointly developed by a plurality of designers. When a large-scale ladder program is developed by a plurality of designers, one ladder program is divided into a plurality of modules, and a designer is assigned to each of these modules. Each designer creates a module he / she is responsible for in each terminal device, and merges (combines) the modules created in different terminal devices to obtain one ladder program.

When performing this merging process in any of the terminal devices, it is necessary to transfer the module between terminal devices. There is no problem if such a merge process is limited to one time, but each time a designer edits a module, the merge process is necessary. Version management is also required, and complicated and inefficient work has occurred with joint development. For this reason, it is desirable to adopt a design method in which modules are uploaded from each terminal device to the PLC and merge processing is performed in the PLC.

  However, in order to perform sufficient error check including consistency between modules, it is necessary to execute error check after merge processing. If merge processing is performed in PLC, error check must also be performed in PLC. I must. If it does so, there existed a problem that a module could not be uploaded from each terminal device with respect to PLC of operation mode.

  Further, the PLC that is performing the error check deletes the ladder program in which the error is found, thereby switching to the operation mode by mistake and preventing the ladder program including the error from being executed. However, in order to analyze the details of the error in detail, it is necessary to obtain a ladder program subject to error check, and the merge processing performed in the PLC must be reproduced in any terminal device. For this purpose, there is a problem in that it is necessary to transfer modules between terminal devices, which is complicated.

Note that Patent Document 1 discloses a conventional technique for analyzing a ladder program in a PLC. This prior art is to output the execution result of the ladder program from the PLC, take it in a debugging device and analyze it, and aims to perform debugging after the execution of the ladder program.
JP 2003-122405 A

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a PLC capable of performing an error check on an uploaded program without changing the program to be executed in the operation mode. And In particular, an object is to provide a PLC that changes a control program to be executed based on an error check result of a program uploaded during an operation mode.

  In addition, when the program to be executed in the operation mode is composed of a plurality of modules and the module for updating this program is uploaded, the uploaded module without changing the program as the execution target An object of the present invention is to provide a PLC that performs error checking. In particular, it is an object of the present invention to provide a PLC that changes a program to be executed based on an error check result for a module uploaded during an operation mode.

  It is another object of the present invention to provide a program creation support apparatus for transmitting a program to the PLC and a computer program for causing a computer to function as the program creation support apparatus.

The programmable controller according to the first aspect of this invention, a programmable capable of switching non-operational mode for stopping the execution of the operation mode and the control program of the execution target repeatedly executes the execution target of the control program which is obtained by merging the plurality of modules and a controller, in order to update a first storage unit for storing the control program of the execution target made of the plurality of modules, some modules of the plurality of modules, edited by the user updates Data receiving means for receiving a module from an external device during the operation mode, a second storage unit for storing an update module received by the data receiving means, and updating among the plurality of modules during the operation mode For non-update modules other than the target module, the first Part Referring to the above for the update module refers to the second storage unit, the non-updated modules and and the updating module merges virtually generates a control program to be updated, the execution target of the control program Error checking means for checking the error of the control program to be updated without changing the update program, and when no error is found by the error check, the update module stored in the second storage unit is And a program changing means for writing to the storage unit.

In the programmable controller according to the second aspect of the present invention, in addition to the above configuration, the program changing means is stored in the second storage unit in synchronization with the repeated execution cycle of the control program to be executed in the operation mode . by writing the update module to the first storage unit, configured to update the execution target of the control program.

A programmable controller according to a third aspect of the present invention is configured such that, in addition to the above configuration, the module includes identification data that is updated every time the user edits .

Fourth PLC system according to the invention, programmable switchable non-operational mode for stopping the execution of the operation mode and the control program of the execution target repeatedly executes the execution target of the control program which is obtained by merging the plurality of modules A PLC system comprising a controller and a program creation support device for generating the module, wherein the program creation support device comprises data transmission means for sending an update module edited by a user to the programmable controller, and is programmable controller, a first memory unit for storing control program of the execution target made of the plurality of modules, in order to update some modules of the plurality of modules, the update module edited by the user , Above luck Data receiving means for receiving from the program creation supporting device during mode, a second storage unit for storing the update module received by said data receiving means, in said operation mode, the update target among the plurality of modules Refer to the first storage unit for non-update modules other than modules, refer to the second storage unit for the update modules, and virtually merge the non-update modules and the update modules to be updated. An error check means for generating a control program and performing an error check of the control program to be updated without changing the control program to be executed; and when the error check finds no error, Program change means for writing the update module stored in the storage unit to the first storage unit; With configured.

  ADVANTAGE OF THE INVENTION According to this invention, PLC which performs the error check of the uploaded program can be provided, without changing the program used as the execution object at the time of operation mode. In particular, it is possible to provide a PLC that changes a control program to be executed based on an error check result of a program uploaded during the operation mode.

  In addition, when the program to be executed in the operation mode is composed of a plurality of modules and the module for updating this program is uploaded, the uploaded module without changing the program as the execution target It is possible to provide a PLC that performs error checking. In particular, it is possible to provide a PLC that changes a program to be executed based on an error check result for a module uploaded during the operation mode.

Embodiment 1 FIG.
[Schematic configuration of the system]
Figure 1 is a diagram illustrating an example of a schematic configuration of according to the first embodiment PLC (Program m able Logic Controller) system of the present invention. This system includes one PLC 1, a plurality of program creation support apparatuses 2 connected to the PLC 1, an input apparatus 3, and an output apparatus 4.

  The PLC 1 is a small controller that is connected to an input device 3 such as a sensor and an output device 4 such as a motor, and generates a control signal to the output device 4 based on a detection signal from the input device 3. , Determined by a program held in the PLC 1. In the PLC 1, the operation mode and the non-operation mode are switched by the user, the program is repeatedly executed in the operation mode, and the execution of the program is stopped in the non-operation mode.

  The program creation support device 2 is a terminal device for a user to create a program for the PLC 1 and may be a dedicated terminal device, but is usually realized by installing dedicated software on a personal computer. The The user creates a program on the program creation support apparatus 2, performs an error check on the created program, compiles the program after the error check, and converts the source code into an object code (execution code). The object code of the program generated in this way is uploaded from the program creation support apparatus 2 to the PLC 1. In addition to uploading, the program in the PLC 1 can be downloaded to the program creation support apparatus 2 and edited.

  The illustrated PLC system is for jointly developing one program by a plurality of designers. Each program creation support device 2 is a terminal device used by different designers, and a plurality of program creation support devices 2 are network-connected to one PLC 1 via a communication cable. Accordingly, each designer can independently edit the program, check errors, compile and upload.

  FIG. 2 is a diagram for explaining the outline of the program 5 for the PLC 1. The program 5 includes a large number of instruction codes that are sequentially executed by the PLC 1. When a single program 5 is jointly developed by a plurality of designers, the program 5 is divided into a plurality of modules modA to modD, and different designers are assigned to the modules modA to modD. That is, the modules modA to modD are respectively created in the different program creation support apparatuses 2 shown in FIG. 1 and uploaded to the common PLC 1. These modules modA to modD are merged (coupled) in the PLC 1 to become the program 5 executed in the PLC 1.

  For each of the modules modA to modD, an error check for each module is performed in each program creation support apparatus 2, and an error check for the entire program 5 obtained by merging the modules modA to modD is performed in the PLC1. .

  Each module modA to modD includes identification data idA to idD, respectively. The identification data idA to idD is data that is generated when a module is newly created and is updated every time the module is changed. Different identification data idA to idD are stored in different modules modA to modD. Even in the same module, different identification data are stored in different versions. However, the same identification data as the module before duplication is stored in the duplicated module. That is, the identification data idA to idD is data unique to module editing.

[Detailed configuration of PLC 1]
FIG. 3 is a block diagram showing a configuration example of the PLC 1 of FIG. The PLC 1 includes a data input / output unit 11, an update data storage unit 12, an error check unit 13, a program update unit 14, a program storage unit 15, a program execution unit 16, an input device I / F (interface) unit 17, and an output device I. / F part 18 is comprised.

The data input / output unit 11 is connected to each program creation support device 2 via a wired or wireless communication line, and performs bidirectional data communication. The program 5 uploaded from the program creation support apparatus 2 is received by the data input / output unit 11 and stored in the update data storage unit 12 . When a download request for the program 5 is received from the program creation support apparatus 2, the program stored in the update data storage unit 12 or the program storage unit 15 is transmitted to the request source program creation support apparatus 2.

  The update data storage unit 12 is a storage unit that stores the program 5 uploaded from the program creation support device 2. When the program 5 is composed of a plurality of modules and a module for updating the program 5 is uploaded, the uploaded module is stored in the update data storage unit 12.

  The program storage unit 15 is a storage unit that stores the program 5 to be executed in the operation mode. Here, it is assumed that the program 5 to be executed includes a plurality of modules modA to modD. In each of the modules modA to modD, identification data idA to idD and update time data are respectively stored. What is written in the program storage unit 15 is the program 5 once stored in the update data storage unit 12 and subjected to error checking. However, in exceptional cases, for example, modules modA to modD are first written in the PLC 1. In such a case, it is possible to directly write from the program creation support apparatus 2 to the program storage unit 15 without performing an error check.

The program execution unit 16 is a processor that operates based on the program 5 in the program storage unit 15. For example, a control signal is generated based on a detection signal input from the input device 3 via the input device I / F unit 17, and the control signal is transmitted to the output device 4 via the output device I / F unit 18 . Output. The program execution unit 16 repeatedly executes the program during the operation mode, but stops the execution of the control program during the non-operation mode.

  The error check unit 13 performs an error check based on programs or modules stored in the update data storage unit 12 and the program storage unit 15. This error check process is executed when a program or module is uploaded to the PLC 1. The target of the error check process is a program obtained by updating the execution target program 5 with the data in the update data storage unit 12. That is, when the program 5 is uploaded and written in the update data storage unit 12, an error check is performed on the program 5. On the other hand, when the module modA is uploaded and written in the update data storage unit 12, an error check is performed on the program that is the execution target program 5 updated with the uploaded new module modA.

  However, the error check unit 13 virtually updates the program 5 with the new module modA, and the data held in the update data storage unit 12 and the program storage unit 15 is not changed by the error check process. That is, the error check unit 13 refers to the program storage unit 15 for modules other than the module modA, and refers to the update data storage unit 12 for the module modA, without changing the execution target program. An error check is performed on the program.

  The program update unit 14 writes the data stored in the update data storage unit 12 to the program storage unit 15 and updates the execution target program 5 when no error is found by the error check unit 13. That is, when the program 5 is held in the update data storage unit 12, the program 5 is written in the program storage unit 15, and the program 5 that was the execution target is deleted. When the module modA is held in the update data storage unit 12, the module modA is written in the program storage unit 15. At this time, if the module modA exists in the program storage unit 15, it is overwritten by the new module modA.

Note that the program update unit 14 can update the program 5 in the program storage unit 15 even in the operation mode. That is, the program being executed by the program execution unit 16 can be updated. For example, the program execution unit 16 updates the program 5 in synchronization with the cycle in which the program 5 is repeatedly executed, so that the program 5 to be executed can be changed without affecting the control operation. It has been updated.

[Detailed Configuration of Program Creation Support Device 2]
FIG. 4 is a block diagram showing a configuration example of the program creation support apparatus 2 of FIG. The program creation support apparatus 2 includes a program storage unit 201, a previous data storage unit 202, a program editing unit 21, an identification data generation unit 22, an error check unit 23, a compilation unit 24, a program verification unit 25, a data input / output unit 26, An error information output unit 27 and a program change confirmation unit 28 are included.

  The program storage unit 201 is a storage unit that stores the program 5 for the PLC 1. The program 5 is a program jointly developed by a plurality of designers. The program 5 includes a plurality of modules modA to modD, and a designer who uses the program creation support apparatus 2 is in charge of creating the module modA. Shall. In this case, the module modA held in the program storage unit 201 is a module created in the program creation support apparatus 2, and the other modules modB to modD are created in the other program creation support apparatus 2. , A module downloaded from PLC1.

  The previous data storage unit 202 is a storage unit that stores identification data idA to idD, and is updated when the program 5 is uploaded and downloaded. For example, if the editing target in the program creation support apparatus 2 is module modA, the identification data idA held in the previous data storage unit 202 is updated when the module modA is uploaded to the PLC 1, and the other identification data idB ˜idD is updated when the modules modB to modD are downloaded from the PLC 1. Therefore, the identification data at the time of the last access to the PLC 1 is always held in the previous data storage unit 202.

  The program editing unit 21 is a means for the user to newly create the program 5 or change the already created program 5. The program can be edited, for example, when the user inputs an operation while watching the screen display, places a new device symbol on the screen, defines parameters such as the device name, or has already been placed. This is done by deleting the device symbol. Here, since the program 5 is composed of a plurality of modules, editing is performed for each module, and identification data and update time data (for example, update date and time) are added to the edited module, and the program storage unit 201 is written.

  The identification data generation unit 22 generates identification data based on the edited program 5 when editing by the program editing unit 21 is completed. If the module modA is edited, identification data idA is generated based on the edited module modA. This identification data is generated as unique data for each editing process. For example, a hash value obtained from the edited module modA can be used as the identification data idA using a predetermined hash function. Also, identification data can be generated based on the date and time when the module modA was edited, the identification information of the designer who performed the editing, the identification information of the terminal device, and the like.

  The error check unit 23 performs an error check on the program 5 held in the program storage unit 201. The user can confirm that no error is included in the program 5 by looking at the error check result. When the program 5 is composed of a plurality of modules, the error check unit 23 performs an error check on the module alone.

  The compiling unit 24 performs a process of converting the source code of the program 5 stored in the program storage unit 201 into an object code. When the program 5 is composed of a plurality of modules, an object code for each module can be generated by this compilation process.

  The data input / output unit 26 performs data input / output with the PLC 1. Here, uploading and downloading of the program 5 to the PLC 1, acquisition of identification data and error information from the PLC 1, and sending of a forced update instruction to the PLC 1 are performed.

  When the program 5 is written (uploaded) to the PLC 1, the program 5 in the program storage unit 201 is uploaded to the PLC 1. When this program is stored in the program storage unit 15 in the PLC 1, identification data included in the program 5 is written in the previous data storage unit 202. When the program 5 is composed of a plurality of modules, it can be uploaded for each module in exactly the same manner.

  When acquiring (downloading) the program 5 from the PLC 1, the acquired program 5 is stored in the program storage unit 201. When the program 5 is downloaded from the program storage unit 15 in the PLC 1, identification data included in the program 5 is also written in the previous data storage unit 202. When the program 5 is composed of a plurality of modules, it can be downloaded for each module in exactly the same manner.

  At the time of program verification, only the identification data idA to idD are acquired without downloading the program 5 and the modules modA to modD from the PLC 1. The identification data idA to idD downloaded from the PLC 1 in this way are output to the program verification unit 25.

  After uploading the program or module, error information is acquired from the PLC 1. This error information is an error check result of the program 5 performed in the PLC 1. The error information acquired from the PLC 1 is output to the error information output unit 27 and the program change confirmation unit 28.

  The program collation unit 25 determines whether the program or module has been updated either in the program creation support apparatus 2 or in the PLC 1 after the last upload or download of the program or module of interest. Determine. This determination processing is performed by comparing identification data held in the program storage unit 201, the previous data storage unit 202, and the PLC 1.

  Whether another person has updated the modules modA to modD in the PLC 1 depends on the identification data idA to idD held in the previous data storage unit 202 and the identification data idA to idD downloaded from the program storage unit 15 in the PLC 1. And can be determined by comparing. If they do not match, it is possible to determine that the modules modA to modD constituting the program to be executed in the PLC 1 have been updated by upload from another program creation support apparatus 2 after the previous update of the data storage unit 202. it can.

  Whether or not the modules modA to modD in the program storage unit 201 have been edited is determined by comparing the previous identification data idA to idD in the data storage unit 202 with the identification data idA to idD in the program storage unit 201. Can be determined. If they do not match, it is possible to determine that the modules modA to modD in the PLC 1 have been updated by the program editing unit 21 after the previous data storage unit 202 has been updated.

  The error information output unit 27 performs an output operation based on the collation result of the program collation unit 25 and the error information acquired from the PLC 1. When the user instructs the program verification process, the verification result is displayed on the screen. Further, when the user instructs to upload a module and the module in the program storage unit 15 of the PLC 1 that is updated by the upload has been updated by another program creation support apparatus 2 first, a warning is given. A message is displayed on the screen, and the user inputs an operation for confirmation, or the upload process is prohibited.

  Further, when error information is acquired from the PLC 1, the error information is displayed on the screen. This error information is a result of an error check performed in the PLC 1 when a program or module is uploaded to the PLC 1. If an error is found, the contents of the error and the location in the program or module where the error was found are displayed. On the other hand, if no error is found, a message to that effect is displayed.

  The program change confirmation unit 28 is a means for confirming the user's intention as to whether or not to forcibly change the execution target program 5 in the PLC 1. The PLC 1 does not update the program 5 to be executed if an error is found in the error check activated by the upload in the operation mode. On the other hand, when an error is found in the error check activated by upload in the non-operation mode, the PLC 1 inquires the program creation support apparatus 2 whether or not to update the execution target program 5. When this inquiry is received, the program change confirmation unit 28 confirms the user's intention and transmits the result to the PLC 1. That is, if the program or module is uploaded in the non-operation mode, even if an error is found in the error check in the PLC 1, if the user approves, the program 5 in the program storage unit 15 of the PLC 1 is updated.

[Upload module]
Steps S101 to S120 in FIGS. 5 to 7 are flowcharts showing an example of the operation of the PLC system in FIG. 1, and show an upload process from the program creation support apparatus 2 to the PLC 1. This upload process is started when the user designates the module modA stored in the program storage unit 201 and instructs the upload to the PLC 1. This upload process can be executed regardless of whether the operation mode of the PLC 1 is the operation mode or the non-operation mode.

  First, in the program creation support apparatus 2, an error check is performed by the error check unit 23 (step S101 in FIG. 5). In this error check, an error check is performed for at least the specified module modA alone. In addition to this, even if the other modules modB to modD held in the program creation support apparatus 2 are used, an error check regarding the consistency between the modules modA to modD constituting the program 5 is finally performed. Good. If an error is found in the error check, the error information output unit 27 displays an error end screen including error information and an “upload failure” message, and ends the upload process without performing the upload (step S102, S103).

  On the other hand, if no error is found in the error check of the module alone (step S101), the module modA is uploaded to the PLC 1 (step S104). The uploaded module modA is temporarily stored in the update data storage unit 12 in the PLC 1, and the program in the program storage unit 15 is not updated.

When a new module modA is stored in the update data storage unit 12, an error check by the error check unit 13 is started (step S105). The target of this error check process is the updated program 5 when the execution target program 5 is updated with the new module modA, but the update data storage unit is not changed without changing the program 5 in the program storage unit 15. 12 and the program storage unit 15 are checked for errors. In other words, the error check unit 13, for a new module modA, refers to the update data storage unit 12, by referring to the program storage unit 15 for other modules ModB～modD, these modules modA~ m odD Virtually merge and check for errors. This error check (step S105) is an error check for the program 5 after the virtual merge. Unlike the error check for the module alone (step S101), the consistency between the modules modA to modD can be checked. .

  If no error is found in the error check in step S105, the execution target program 5 is updated by the uploaded module (steps S106 and S107 in FIG. 6). That is, the program update unit 14 writes the new module modA in the update data storage unit 12 into the program storage unit 15. In addition, the program creation support apparatus 2 is notified of the normal end of the upload. In the program creation support apparatus 2, based on this notification, the identification data of the uploaded module modA is written in the previous data storage unit 202 (step S108). Also, based on the notification, a normal completion screen consisting of an “upload success” message is displayed by the error information output unit 27 (step S109), and the upload process ends.

  On the other hand, when an error is found in the error check in step S105, the subsequent operation differs depending on whether or not the error is fatal and whether or not the operation mode of the PLC 1 is in operation (step S110). To S114).

  If the detected error is a fatal error that cannot update the execution target program 5, the program creation support device 2 displays an error completion screen including error information and an “upload failure” message. Then, the upload process ends (steps S110 and S111). When the error information is fatal, for example, the size of the updated program exceeds the capacity of the program storage unit 15, or the maximum number of modules allowed by the PLC 1 by adding modules is exceeded. This is the case.

  Even if the error information is not fatal, when the operation mode of the PLC 1 is the operation mode, the program creation support apparatus 2 displays an error end screen including the error information and an “upload failure” message. The upload process is terminated (steps S112 and S113). During the operation mode, it is dangerous to update the program to be executed to a program in which an error has been found. Therefore, such a program update is prohibited.

  When the error information is not fatal and the operation mode of the PLC 1 is the non-operation mode, the error information is displayed on the program creation support device 2 (step S114), The message “Do you want to update?” Is displayed on the screen, and the user's intention is confirmed (step S115 in FIG. 7). The user uses a pointing input means such as a mouse to select whether to forcibly update the program.

  At this time, if the user does not approve the forced update, the program creation support apparatus 2 displays a message “End without updating the program” on the screen, and ends the upload process (steps S116 and S117). On the other hand, if the user approves the update, the execution target program 5 is updated by the uploaded module, and the completion of the update is notified to the program creation support apparatus 2 (step S118). In the program creation support apparatus 2, based on this notification, the identification data of the uploaded module modA is written in the previous data storage unit 202 (step S119). Further, based on the above notification, a message “Program has been forcibly updated” is displayed on the screen (step S120), and the upload process ends.

[Download module]
Steps S201 to S204 in FIG. 8 are flowcharts showing an example of the operation of the PLC system in FIG. 1, and show module download processing from the PLC 1 to the program creation support apparatus 2. This download process is started when the user designates a module, for example, module modB, stored in the program storage unit 15 in the PLC 1 and instructs the program creation support apparatus 2 to download. This upload process can be executed regardless of whether the operation mode of the PLC 1 is the operation mode or the non-operation mode.

  First, a download request designating the module modB is transmitted from the program creation support apparatus 2 to the PLC 1 (step S201). The PLC 1 that has received this download request reads out the module modB held in the program storage unit 15 and transmits it to the request source program creation support apparatus 2. This module is received by the data input / output unit 26 in the program creation support apparatus 2 (step S202). The data input / output unit 26 extracts the identification data idB from the received module modB, and updates the identification data in the previous data storage unit 202 (step S203). After the previous data storage unit 202 is updated, the module modB is written in the program storage unit 201 (step S204). In addition, when downloading the module hold | maintained at the update data storage part 12 in PLC1, step S203 is abbreviate | omitted among the said steps.

[Program verification]
Steps S301 to S306 in FIG. 9 are flowcharts showing an example of the operation of the program creation support apparatus 2 in FIG. 4 , and show program collation processing. This program verification processing is executed by the program verification unit 25 when the user instructs program verification in the program creation support apparatus 2.

  When the user designates the program 5 to instruct program verification, the program verification unit 25 stores the identification data idA to idD and the update time data for all the modules modA to modD belonging to the program in the program storage unit 15 in the PLC 1. (Step S301). At this time, the modules modA to modD themselves may be downloaded. However, if only the identification data idA to idD and update time data necessary for program verification are downloaded, the download time can be greatly shortened.

  Next, the identification data idA to idD are read from the previous data storage unit 202 (step S302), and compared with the downloaded identification data idA to idD (step S303). That is, for each of the modules modA to modD to be collated, the identification data held in the previous data storage unit 202 is compared with the identification data held in the program storage unit 15 of the PLC 1.

  Similarly, identification data idA to idD and update time data are read from the program storage unit 201 (step S304), and the identification data idA to data in the previous data storage unit 202 are checked for each of the modules modA to modD to be collated. Comparison with idD is performed (step S305).

  The error information output unit 27 displays the comparison results of steps S303 and S305 on the screen to notify the user (step S306). For example, the comparison results in steps S303 and S305 are displayed on the screen in association with each of the modules modA to modD.

In this program collation process, the identification data is downloaded between the program creation support apparatus 2 and the PLC 1, but the module is not uploaded or downloaded. For this reason, the previous data storage unit 202 is not updated.

[Error information output example 1]
FIG. 10 is a diagram showing an example of error information output in the program creation support apparatus 2, and shows an example of screen display by the error information output unit 27. This display screen includes a program display area 30 and an error information display area 31. The program display area 30 is an area in which the program 5 is displayed graphically, similar to the display at the time of program editing, and the program 5 is displayed as a combined state of a plurality of device symbols 32.

  The error information display area 31 is an area for displaying error information received from the PLC 1. In this figure, two pieces of error information 33 are displayed with different lines. Here, as the error information 33, an error occurrence location 34, an error number 35, an error message 36, and a command word 37 are displayed. The error occurrence location 34 is information on the error occurrence position, and is specified by, for example, the module name “cp053”, the row number “00019”, and the column number “02”. The error number is a code number indicating a predetermined error type. The error message 36 is a character string that is associated with a code number in advance. The instruction word 37 is an instruction word in which an error is found.

  FIG. 11 is an example of a screen display showing an error occurrence location on a program. If the user selects any one of the error information 33 displayed in the error information display area 31 on the display screen of FIG. 10, the module including the error occurrence location is displayed in the program display area 30, and the error occurrence location is displayed. The device symbol becomes a highlight (emphasis) display 68. For example, when the user clicks in the error information display area 31 using a pointing device such as a mouse, error information corresponding to the clicked line is selected, and the device related to the error information is displayed in the program display area 30. Is done.

  However, when the error information selected by the user is a module modB to modD that is not held in the program creation support device 2, the modules modB to modD are downloaded from the program storage unit 15 in the PLC 1 and displayed as a program. Displayed in area 30. Note that it is desirable to acquire the module related to the error information when acquiring the error information from the PLC 1. For example, the PLC 1 may be configured to send the module related to the error information together with the error information to the program creation support apparatus 2, or based on the error information acquired by the program creation support apparatus 2 from the PLC 1. Thus, the PLC 1 can be configured to request downloading of a module related to the error information.

[Error information output example 2]
FIG. 12 is a diagram showing another example of error information output in the program creation support apparatus 2 and shows a PLC verification / synchronization screen 6 on which a program verification result and error information are displayed simultaneously.

  The PLC verification / synchronization screen 6 is displayed by the error information output unit 27. On the PLC verification / synchronization screen 6, a verification button 61, a PLC write button 62, a PLC read button 63, and a verification result display area 64 are provided. These buttons 61 to 63 can be operated using a pointing input unit such as a mouse, and the user can instruct a program collation process, an upload process, or a download process.

  When the user operates the collation button 61, the program collation process shown in FIG. 9 is executed, and the collation result is displayed in the collation result display area 64. In the illustrated collation result display area 64, an example is shown in which the modules A to D included in the program 5 designated by the user are displayed on different lines.

  The area on the left side of each row is an editor display column 641 in which the module name held in the program storage unit 201 of the program creation support apparatus 2 and its update time data are displayed. Similarly, the area on the right side of each row is a PLC display column 643 in which the module name held in the program storage unit 15 in the PLC 1 and its update time data are displayed.

  The center area of each line is a collation result display column 642 for displaying collation results by the program collation unit 25 in characters. “OK” is displayed in the collation result display field 642 for modules whose collation results in steps S303 and S305 are identical. On the other hand, for any module that does not match, nothing is displayed in the collation result display field 642, and the module in the editor display field 641 or the PLC display field 643 becomes a highlight (highlight) display 66. That is, if there is a mismatch in step S303, the module in the PLC display field 643 is highlighted 66, and if there is a mismatch in step S305, the module in the editor display field 641 is highlighted. The display 66 is displayed. In this way, the comparison results of steps S303 and S305 are displayed in association with each module.

  A highlight display 67 indicated by hatching in the figure indicates a module in which an error has occurred during the upload processing of FIGS. The highlight display 67 is updated when the program is uploaded. Although not shown, both can be displayed so that “upload failure” in which updating of the program to be executed has failed and forced program update after error detection can be distinguished.

  The check box 65 is a check box for the user to specify a module to be uploaded or downloaded, and is provided at the left end of each row. The user clicks the check box 65 to select a module to be uploaded or downloaded.

  The PLC write button 62 is an operation button for instructing uploading to the PLC 1. If the user operates the PLC write button 62, the upload process shown in FIGS. The uploaded module is a module selected by the user operation of the check box 65.

  The PLC read button 63 is an operation button for instructing download from the PLC 1. If the user operates the PLC read button 63, the download process shown in FIG. 8 is executed. The downloaded module is a module selected by the user operation of the check box 65.

  An example of the collation result of each module A to D shown in FIG. 12 will be described. Although the module A in the program creation support apparatus 2 has been edited, it is understood that this editing is not reflected in the module A in the PLC 1 and it is necessary to upload the module A to the PLC 1. Also, it can be seen that the module A in the PLC 1 has not been updated by another person and that the uploading can be performed safely. However, in this example, the module A is highlighted 67 indicating the upload failure. In other words, it can be seen that uploading of the edited module has already been attempted, and as a result, an error was found in the error check at the time of upload, and the execution target program could not be updated.

  The module B in the program creation support apparatus 2 is not edited, but the module B in the PLC 1 is updated by another program creation support apparatus 2. For this reason, in order to perform a simulation correctly, it turns out that the module B needs to be downloaded from PLC1.

  “OK” is displayed for the module C, indicating that the modules in the program creation support apparatus 2 and the PLC 1 match. In this case, it is understood that neither upload nor download is required for the module C.

  Although the module D in the program creation support apparatus 2 has been edited, this editing is not reflected in the module D in the PLC 1. On the other hand, the module D in the PLC 1 has been updated by another program creation support device 2 first. In this case, uploading of the module D to the PLC 1 is overwritten with the module D in the PLC 1 previously updated by another person.

  Note that the update data storage unit 12 and the program storage unit 15 in the above embodiment do not have to be physically partitioned or fixedly partitioned storage devices. These storage units 12 and 15 can be realized as follows, for example.

  FIG. 13 is a diagram illustrating a specific configuration example of the update data storage unit 12 and the program storage unit 15. (A) in the figure is a diagram showing a memory space of a storage device provided in the PLC 1, and is divided into a plurality of memory areas A1 to A8 in advance. (B) in the figure is an allocation table for dynamically allocating each of these memory areas A1 to A8 to the update data storage unit 12 or the program storage unit 15.

  Here, the modules A to D constituting the program 5 to be executed are stored in the memory areas A1 to A4 and A7, and these memory areas A1 to A4 and A7 are stored in the program storage unit by the allocation table. 15 is assigned. Since the module B is larger than the size of the memory area A2, the module B is stored across the two memory areas A2 and A3. The uploaded module A 'is stored in the memory area A6, and this memory area A6 is allocated to the update data storage unit 12 by the allocation table of (b).

  Therefore, the program execution unit 16 operates with reference to the memory areas A1 to A4 and A7, and the error check unit 13 performs error check with reference to the memory areas A2 to A4, A6 and A7. When the program A to be executed is updated by replacing the module A with the module A ′, the program update unit 14 allocates the memory area A6 to the program storage unit 15, and the memory area A1 is unused. The allocation table may be changed so that the module A ′ does not need to be moved in the memory space.

  In the above embodiment, an example in which the program 5 is mainly composed of a plurality of modules has been described. However, the present invention is not limited to such a case. That is, the present invention can be applied to a program 5 (a program composed of one module) that is not divided into modules.

It is the figure which showed an example of schematic structure of the PLC system by Embodiment 1 of this invention. It is a figure for demonstrating the outline of the program 5 for PLC. It is the block diagram which showed one structural example of PLC1 of FIG. It is the block diagram which showed the example of 1 structure of the program creation assistance apparatus 2 of FIG. It is the flowchart which showed an example of the upload process of a module (the 1). It is the flowchart which showed an example of the upload process (the 2). It is the flowchart which showed an example of the upload process (the 3). It is the flowchart which showed an example of the download process. It is the flowchart which showed an example of the program collation process. It is the figure which showed an example of the error information output in the program creation assistance apparatus. It is an example of the screen display which showed the error occurrence location on the program. It is the figure which showed the other example of the error information output in the program creation assistance apparatus. 3 is a diagram illustrating a specific configuration example of an update data storage unit 12 and a program storage unit 15. FIG.

Explanation of symbols

2 Program creation support device 3 Input device 4 Output device 5 Program 6 PLC verification / synchronization screen 11 Data input / output unit 12 Update data storage unit 13 Error check unit
1 4 Program update unit 15 Program storage unit 16 Program execution unit 17 Input device I / F unit 18 Output device I / F unit 21 Program editing unit 22 Identification data generation unit 23 Error check unit 24 Compile unit 25 Program verification unit 26 Data input Output unit 27 Error information output unit 28 Program change confirmation unit
3 0 Program display area 31 Error information display area 32 Device symbol 33 Error information 34 Error location 35 Error number 36 Error message 37 Command word 61 Program verification button 62 PLC write button 63 PLC read button 64 Verification result display area 65 Check box 66, 67, 68 Highlight display 201 Program storage unit 202 Previous data storage unit 641 Editor display column 642 Verification result display column 643 PLC display column idA to idD Identification data modA to modD Module

Claims (4)

In a programmable controller capable of switching between an operation mode for repeatedly executing an execution target control program obtained by merging a plurality of modules and a non-operation mode for stopping execution of the execution target control program,
A first storage unit for storing the control program of the execution target made of the plurality of modules,
A data receiving means for receiving an update module edited by a user from the external device during the operation mode in order to update some of the plurality of modules;
A second storage unit for storing the update module received by the data receiving means;
During the operation mode, the first storage unit is referred to for a non-update module other than the module to be updated among the plurality of modules, the second storage unit is referred to for the update module, and the non-update module And the update module are virtually merged to generate an update target control program, and an error check means for checking the error of the update target control program without changing the execution target control program ,
A programmable controller comprising: program changing means for writing an update module stored in the second storage unit into the first storage unit when no error is found by the error check. The program changing means writes the update module stored in the second storage unit to the first storage unit in synchronization with the repeated execution cycle of the control program to be executed in the operation mode, thereby the programmable controller of claim 1, characterized in that to update the control program.   The programmable controller according to claim 1, wherein the module includes identification data that is updated each time editing is performed by a user. Programmable controller capable of switching between an operation mode in which an execution target control program obtained by merging a plurality of modules is repeatedly executed and a non-operation mode in which execution of the execution target control program is stopped, and creation of a program for generating the module In a PLC system consisting of a support device,
The program creation support device includes data transmission means for transmitting an update module edited by a user to the programmable controller,
The programmable controller, in order to update a first storage unit for storing the control program of the execution target made of the plurality of modules, some modules of the plurality of modules, edited by the user updates Data receiving means for receiving modules from the program creation support apparatus during the operation mode, a second storage unit for storing update modules received by the data receiving means, and the plurality of modules during the operation mode The non-update module other than the module to be updated is referred to the first storage unit, the update module is referred to the second storage unit, and the non-update module and the update module are virtually merged. to generate a control program to be updated, to change the execution target of the control program And error checking means for performing error checking of a control program of the update target without, if no error is found by the error check, the update module stored in said second storage unit to the first storage unit A PLC system comprising a program change means for writing.