JP7188631B1 - Programmable logic controller, support device, display device, logging method, support method, display method - Google Patents

Abstract

An object of the present invention is to enable logging without affecting the execution of user applications and the control of devices. A processing execution unit 61 repeatedly executes a cycle of control processing of S200 including input processing of S210, program execution processing of S220, output processing of S230, system processing of S240, and logging processing of S250. In the logging process of S250, it is determined whether or not the execution time of one cycle of the control process of S200 falls within a preset control cycle, and S200 in the cycle in which it is determined that the execution time does not fall within the control cycle is performed. In the logging process of S250 included in the control process of , the process of interrupting the collection of the value of the variable is included. [Selection drawing] Fig. 12

Description

The present invention relates to the technology of programmable logic controllers.

A programmable logic controller is a controller that controls manufacturing equipment, transport equipment, and inspection equipment in factory automation. Programmable logic controllers control various control devices by executing user application programs such as ladder programs created by users.

When an abnormality occurs in the control of equipment by a control device, it is desirable to identify the cause of the abnormality. In addition, there is a demand for recording information related to device control and verifying the information afterward, not limited to the occurrence of such an abnormality. Therefore, a first technique is proposed in which a user presets conditions for recording data history in a control device, and the control device logs data indicating the operating states of the devices and the control device itself based on these conditions. is known (see, for example, Patent Document 1).

FIG. 1 shows an example of the execution period of each process executed by the control device in this first technique. The upper part in FIG. 1 shows the execution period of each process when the logging process is not executed, and each process of the input process, the program execution process, and the output process is executed in this order in each cycle of the control cycle. It means that In addition, the lower part in FIG. 1 shows the execution period of each process when the logging process is executed. Indicates that the process will be executed.

Also, as another background art, a second technique is known which will be described below. In programmable logic controllers, among the processes not managed by the application scheduler, there are cases where priority is given to processes that affect message response performance, such as data processing systems, and there are cases where priority is given to execution performance of user applications. This second technique allows the user to set the priority of both (see Patent Document 2, for example).

FIG. 2 shows an example of band ratio adjustment in the second technique. In FIG. 2, "task 1", "task 2", and "task 3" represent tasks in which user applications are executed, and "task A" and "task B" represent communication processing and system maintenance. It represents a task of processing other than the user application, such as processing for Also, in this example, one control cycle is divided into an application band period and a system band period. User application tasks are executed in the application band, and processing tasks other than the user application are executed in the system band. is executed. Also, within each band, each task is executed in an order according to its priority.

In FIG. 2, the upper part shows the situation before adjustment of the band ratio, and the lower part shows the situation after adjustment. The second technique allows the user to adjust the ratio between the application bandwidth and the system bandwidth in each control cycle according to the user's purpose, thereby giving priority to user application performance or system processing. It is possible to change whether to give priority to performance.

Japanese Patent Application Laid-Open No. 2020-13526 JP 2008-146357 A

In the above-described first technique, the addition of the logging process lengthens the control cycle, which delays the execution periods of other input processes, program execution processes, and output processes. It may not work as intended by the user.

In one aspect, an object of the present invention is to enable logging without affecting execution of user applications and control of devices.

In one embodiment, a programmable logic controller includes a process execution unit and a ring buffer . The processing execution unit repeatedly executes a cycle of control processing including input processing, program execution processing, output processing, system processing, and logging processing. The input process is a process of fetching input data sent from an external device. The program execution process is a process of executing a user application program using the input data. The output process is a process of outputting the execution result of the user program to control an external device. System processing is processing that manages the operation of the programmable logic controller itself. The logging process is a process of collecting values of variables used in the user application program. The ring buffer stores collected data in which the time when the value of the variable was collected by the logging process and the value of the variable collected at the time of collection are associated with each other each time the value of the variable is collected. The logging process determines whether the execution time of one cycle of the control process falls within a preset control cycle, and is included in the control process of the cycle determined that the execution time does not fall within the control cycle. In the logging process that is performed, as a process of interrupting the collection of the value of the variable, the value of the variable collected in the logging process included in the control process of the cycle determined that the execution time does not fit within the control cycle including processing for discarding the collected data from the ring buffer .

In another embodiment, a programmable logic controller support device that repeatedly executes the control processing cycle described above includes a program analysis unit, a selection unit, a first output unit, and a second output unit. The program analysis unit analyzes the user application program and extracts variables used in the user application program. The selection unit selects variables to be collected by the logging process from among the variables extracted by the program analysis unit as target variables. The first output unit outputs information specifying the target variable as logging setting data for the programmable logic controller. The second output unit determines whether the execution time of one cycle of the control process when the logging process is executed for all the target variables selected by the selection unit falls within a preset control cycle. , when the execution time of the control process does not fall within the control cycle, output caution information, and execute the logging process for all the target variables selected by the selection unit 1 cycle of the control process is further output as an estimated control period .

In still another embodiment, in another embodiment, a display device that displays values of variables collected by logging processing by a programmable logic controller that repeatedly executes the above-described control processing cycle, A reading unit, a display unit, and a display control unit are provided. The reading unit is logging collected data in which collected data in which the values of variables collected by the logging process are associated with the collection times of the values of the variables are arranged in the order of collection times, and stored in the external storage device by the programmable logic controller. The saved logging collection data is read from the external storage device. Based on the logging collection data read out from the external storage device, the display unit displays the collection time and the value of the variable in association with each other. When the display control unit finds traces of interruption of the logging process from the logging collection data read from the external storage device, the display control unit displays a display indicating the loss of the value of the variable due to the interruption. The information is further displayed on the display in association with the collected collection time.

According to one aspect, it is possible to suppress the influence of execution of logging on execution of user applications and control of devices.

FIG. 5 is a diagram showing an example of an execution period of each process executed by the control device in the first technology; FIG. 10 is a diagram showing an example of band ratio adjustment in the second technique; It is a figure which shows the structural example of a PLC system. It is the figure which showed the example of the execution period of each process which PLC performs. It is the figure which showed the hardware structural example of PLC. It is the figure which showed the hardware structural example of PC. It is the figure which showed the functional structural example of a support apparatus. FIG. 7 is a diagram illustrating a method of setting conditions for executing logging processing; It is a screen example of a UI screen. FIG. 4 is a diagram showing an example of the data structure of logging setting data; FIG. 4 is a diagram showing an example of the data structure of collection target setting information; It is the figure which showed the functional structural example of PLC. It is a figure explaining the logging execution method by PLC. 5 is a flow chart showing details of processing contents of logging processing and saving processing; FIG. 4 is a diagram showing an example of the data structure of logging collection data; It is the figure which showed an example of the data structure of collected data. 8 is a flowchart showing details of processing contents of collection processing; FIG. 11 is a diagram (part 1) for explaining the use of the collection timing counter value; FIG. 12 is a diagram (part 2) for explaining the use of the collection timing counter value; It is the figure which showed the hardware structural example of the collection data display apparatus. It is the figure which showed the functional structural example of the collection data display apparatus. It is a figure explaining an example of the method of displaying collection data. It is a figure explaining the detail of a program display process. It is the 1st example of the display drawing of collected data. It is a screen example of a warning screen. It is a figure explaining the detail of a waveform display process. It is a first example of a waveform display screen of acquired data. FIG. 10 is a diagram illustrating details of logging file analysis/conversion processing; FIG. 10 is a flow chart showing processing contents of logging file analysis/conversion processing; FIG. It is a figure explaining the detail of a display control process. FIG. 11 is a second example of a display drawing of collected data; FIG. It is a second example of a waveform display screen of collected data.

Hereinafter, embodiments will be described in detail with reference to the drawings.

FIG. 3 shows a configuration example of the PLC system 10. As shown in FIG. This PLC system 10 includes a PLC 1 , a PC 2 , an input/output module 3 and a communication module 4 . PLC 1 and PC 2 are connected via communication cable 6 . "PLC" is an abbreviation for programmable logic controller. "PC" is an abbreviation for personal computer.

The PLC 1 comprehensively controls various control devices installed in a factory or the like.

PC2 provides a function as a support device that supports PLC1. The PC 2 is used, for example, to edit user application programs. In the following description, the user application program may also be referred to as "user program". The user program may be created using a graphical programming language such as a ladder language conforming to IEC61131-3, or a motion program in the form of a flow chart such as a sequential function chart (SFC). Also, the user program may be created using a high-level programming language such as the C language, for example.

In addition, as will be described later, the PC 2 also provides a function of setting conditions for execution of logging processing.

The PLC 1 is configured such that external devices such as one or more input/output modules 3 and communication modules 4 are detachable. PLC 1 , input/output module 3 and communication module 4 are connected via communication bus 7 .

The input/output module 3 converts a signal from a servo amplifier, an encoder, or a sensor into an electric signal, and may input/output a digital signal or an analog signal.

A communication module 4 provides a communication interface with other devices.

FIG. 4 shows an example of the execution period of each process executed by the PLC 1 in the PLC system 10 of FIG.

The PLC 1 repeatedly executes control processing cycles including input processing, program execution processing, output processing, and system processing. The input process is a process of fetching input data received from the input/output module 3, which is an external device. The program execution process is a process of executing a user program created by the user. Execution of this user program uses the input data taken in by the input process. The output process is a process of controlling the input/output module 3 by outputting the execution result of the user program and reflecting the execution result in the output of the input/output module 3 . The system processing is processing for managing the operation of the PLC 1 itself and maintaining proper operation.

As shown in the upper part of FIG. 4, the PLC 1 executes input processing, program execution processing, output processing, and system processing in this order in each control cycle. Note that the length of the control cycle is designated by the user.

The control processing executed by the PLC 1 further includes logging processing in addition to these processing. The logging process is a process of collecting the values of variables used in the user program, recording data indicating the operating state of each component of the PLC system 10 including the PLC 1 itself, and storing it as a history. .

As shown in the lower part of FIG. 4, the PLC 1 executes the logging process during the execution period of the system process following the execution period of the output process in each control cycle. In this way, the PLC 1 performs the logging process during the execution period of the system process, thereby affecting the execution period of the input process, program execution process, and output process related to the control of the user program and equipment. It allows you to do the logging process without having to

Note that the execution time of the logging process may be adjustable by changing the ratios of the execution periods of the program execution process, the system process, and the logging process.

Next, the PLC1 and PC2 in the PLC system 10 will be explained in more detail.

First, the hardware configuration of the PLC 1 will be described with reference to the hardware configuration example shown in FIG. This PLC 1 has a communication I/F 11 , a CPU 12 , a bus controller 13 , a memory 14 and a storage device I/F 15 . All of these components are connected to the internal bus 16 and can exchange data with each other. Note that "CPU" is an abbreviation for central processing unit. "I/F" is an abbreviation for interface.

The communication I/F 11 is connected to the communication cable 6 and manages the transfer of various data with the PC 2 .

The CPU 12 executes various programs such as a user program, a system program for managing the operation of the PLC 1 itself, and a logging execution program.

The bus controller 13 is connected to the communication bus 7 and manages transmission and reception of various data between the input/output module 3 and the communication module 4 which are external devices.

The memory 14 is, for example, a semiconductor memory and includes a RAM area and a ROM area. The RAM area is used as a storage area for temporarily storing various data when the CPU 12 executes various programs. The ROM area is an area in which various programs and data are stored, and non-volatile memory is used, for example. Note that "RAM" is an abbreviation for random access memory. "ROM" is an abbreviation for read-only memory.

The storage device I/F 15 manages writing processing and reading processing of various data to and from an external storage device 17 such as a memory card.

Next, the hardware configuration of the PC 2 will be described with reference to the hardware configuration example shown in FIG. This PC 2 has a CPU 21 , a memory 22 , an input device 23 , a display device 24 , an auxiliary storage device 25 and a communication I/F 26 . All of these components are connected to the internal bus 27 and can exchange data with each other.

The CPU 21 provides, for example, a user program editing function and a function for setting conditions for executing logging processing by executing a predetermined program using the memory 22 .

The input device 23 is, for example, a keyboard, a pointing device, or the like, and is used to input instructions or information from the user.

The display device 24 is used, for example, to make an inquiry or instruction to the user and to display and output the processing result.

The auxiliary storage device 25 is a magnetic disk device, an optical disk device, a magneto-optical disk device, or the like, and may be, for example, a hard disk drive or a flash memory. The PC 2 can store programs and data in the auxiliary storage device 25 and load them into the memory 22 for use.

The communication I/F 26 is connected to the communication cable 6 and manages various data exchanges with the PLC 1 .

<Logging settings>

Next, in the PLC system 10 of FIG. 3, the method of setting the execution conditions of logging processing to PLC1 is demonstrated.

First, FIG. 7 will be described. FIG. 7 is a diagram showing an example of the functional configuration of the support device 30. As shown in FIG. This configuration example is an example in which the support device 30 provides a function of setting conditions for execution of logging processing by the PLC 1 . In the PLC system 10, the PC 2 provides the functions of the support device 30 by causing the PC 2 to execute a predetermined setting tool program.

7, the support device 30 includes a program analysis section 31, a selection section 32, a first output section 33, and a second output section . It is assumed that the control period for causing the PLC 1 to perform the aforementioned control processing is preset in the support device 30 by the user.

The program analysis unit 31 analyzes a user program to be executed by the PLC 1 and extracts variables used in the user program.

The selection unit 32 selects variables to be collected by the logging process performed by the PLC 1 from among the variables extracted by the program analysis unit 31 . The variables selected by the selection unit 32 are called "target variables".

The first output unit 33 outputs information specifying the target variable selected by the selection unit 32 as the logging setting data 42 . Although the details will be described later, the logging setting data 42 is, for example, a storage area on the memory 14 used to hold the value of the target variable when the user program is executed in the PLC 1 as information specifying the target variable. contains information that identifies the location of the

The second output unit 34 determines whether the execution time of one cycle of the above-described control processing when the PLC 1 executes the logging processing for all the target variables selected by the selection unit 32 falls within a preset control cycle. determine what Here, if the execution time does not fall within the control period, caution information is output to call attention to this fact. By doing so, it becomes possible for the user to recognize that the logging data may be lost when the PLC 1 is caused to perform the logging process based on the logging setting data 42 at this time. In addition, by doing so, it is possible to encourage the user to consider limiting the number of variables to be collected, and as a result, the effect of logging execution on user program execution and device control is suppressed.

In addition, the second output unit 34 further sets the estimated control cycle to the time estimated to be required for executing one cycle of the above-described control processing when the logging processing is executed for all the target variables selected by the selection unit 32. You may make it output.

A method of setting conditions for execution of logging processing, which is an example of a support method performed by the support device 30 having such a configuration, will be described in more detail with reference to FIG.

The support device 30 is equipped with a setting tool 40 . The PC 2 provides the function of the setting tool 40 by causing the CPU 21 to execute a predetermined setting tool program.

Project data 41 is input to the setting tool 40 . The project data 41 includes information on the system configuration of the PLC system 10, a user program to be executed by the PLC 1, and function setting information on the input/output module 3, the communication module 4, etc., which are external devices provided in the PLC system 10. Information. Here, it is assumed that the project data 41 has already been created by the user by executing a predetermined project data editing program on the PC 2, for example, and is already stored in the auxiliary storage device 25, for example.

The setting tool 40 first performs the collection target setting process of S<b>110 for the project data 41 . This process is a process of setting variables to be logged from the variables used in the user program, and is a process of providing the functions of the program analysis unit 31 and the selection unit 32 in the support device 30 of FIG. be.

The process of S110 includes the program analysis process of S111. The program analysis process is a process of analyzing a user program included in the project data 41 and extracting variables used in the user program. In the collection target setting process of S110, a process of selecting a target variable, that is, a variable to be collected by the logging process performed by the PLC 1 from the variables extracted by executing the program analysis process is further performed.

FIG. 9 will now be described. FIG. 9 shows an example of the UI screen 100 used in the collection target setting process of S110. "UI" is an abbreviation for user interface.

In the screen example of FIG. 9 , the UI screen 100 includes a program selection section 101 , an extracted variable display section 102 and a target variable display section 103 . When the PC 2 in FIG. 6 provides the functions of the support device 30 , this UI screen 100 is displayed by the display device 24 .

Information indicating the user program included in the project data 41 is displayed in the program selection portion 101 . In this embodiment, it is assumed that a task is configured as an aggregation of a plurality of programs, and a user program is configured as an aggregation of a plurality of tasks. In the screen example of FIG. 9, "application name" is the name of the user program, "task 1", "task 2", and "task 3" are the names of the respective tasks, and "program", "program N" is the name of each program belonging to each task. This screen example shows that the relationship between the user program, each task, and each program is expressed in a tree format.

When the user performs an operation to select one of the program names displayed in the program selection section 101, the program corresponding to the selected name is subjected to the program analysis processing of S111, and the program is used in the program. variables are extracted. Note that when an operation is performed to select a task name instead of a program name, variables are extracted from each program belonging to the task corresponding to the selected name. At this time, the extracted variable names are listed in the extracted variable display section 102 .

When the user selects one or more of the variable names displayed in the extracted variable display area 102 and presses the registration button 104, the variable corresponding to the selected name is selected as the target variable. selected. At this time, the names of the selected target variables are listed in the target variable display section 103 .

When the user selects one or more of the target variable names displayed in the target variable display area 103 and presses the release button 105, the variable corresponding to the selected name is displayed. Excluded from the selection result of the target variable.

Further, when the user presses the collective registration button 106, all the variables whose names are displayed in the extracted variable display section 102 are selected as target variables, and the names are displayed as a list in the target variable display section 103. be done. On the other hand, when the user presses the collective release button 107, all the variables whose names are displayed in the target variable display section 103 are excluded from the target variable selection results.

In the collection target setting process of S110, the total amount of data collected when the logging process is executed for all the target variables selected as described above is calculated based on the project data 41. FIG. The total amount of data obtained is displayed in the collected data size display section 108 on the UI screen 100 .

Further, the execution time of each of the input processing, program execution processing, output processing, and system processing described above in one cycle of the control processing performed by the PLC 1 can be calculated from the project data 41 . In the collection target setting process of S110, the calculation of the execution time of each of these processes and the calculation of the execution time of the logging process estimated when the logging process is executed for the target variables selected as described above are performed. Then, the total value of the obtained execution time of each process is calculated. The total value of this execution time is the estimated time required for execution of one cycle of the aforementioned control processing executed by the PLC1. This total value is displayed in the estimated control cycle display section 109 on the UI screen 100 .

By displaying the collected data size and the estimated control cycle on the UI screen 100, for example, it is possible to remind the user to consider the selection of target variables to fit within the preset control cycle. . In addition, if the user intends to give priority to the logging process, it is possible to remind the user to consider changing the preset control cycle.

Returning to the description of FIG. In S120, collection operation setting processing is performed. This process is a process of creating information for setting the operation of the logging process. With this information, the PLC 1 can set, for example, the collection timing of the value of the target variable, which is the data to be collected, the period during which the data is collected, and the save timing for the PLC 1 to save the collected data in the external storage device 17. performed against.

Following the processing of S110 and S120 described above, the setting content confirmation processing of S130 is performed. This process determines whether or not the execution time of one cycle of the above-described control process when the PLC 1 executes the logging process for all the target variables selected by the process of S110 falls within a preset control cycle. It is a process to

In this process, for example, the execution time of the input process, program execution process, output process, and system process in one cycle of the control process executed by the PLC 1 is calculated from the project data 41 . Then, the total of these execution times is subtracted from the preset control cycle. The time obtained by this subtraction is the time during which the logging process can be executed, and this time is called "maximum processing time". Next, based on this maximum processing time, the maximum size of data that can be collected within this time is determined. Then, this maximum size is compared with the total data amount (the value displayed in the collected data size display section 108 on the UI screen 100) calculated by the process of S110, and the total data amount is compared with the maximum data amount. It is determined whether it is less than or equal to size.

Here, when the total data amount exceeds the maximum size, the execution time of one cycle of the above-described control processing when the PLC 1 executes the logging processing for all the selected target variables is set in advance. A determination result is made that it does not fit within the current control cycle. At this time, when the PLC 1 executes the logging process for all of the selected target variables, caution information is output indicating that the execution time does not fall within the preset control cycle. When the function of the support device 30 is provided by the PC 2 in FIG. 6, such caution information is displayed by the display device 24.

As described above, the function of the second output unit 34 in the support device 30 of FIG. 7 is provided by the setting content confirmation process of S130.

Next, a setting file creation process of S140 is performed. This setting file creation process is a process for providing the function of the first output unit 33 in the support device 30 of FIG.

The setting file creation process is a process of outputting, as the logging setting data 42, the information specifying the target variable selected by the process of S110 and the operation setting information of the logging process set by the process of S120. This logging setting data 42 is transferred to the PLC 1 , and in the PLC 1 operation settings for the logging process are made based on the contents of the logging setting data 42 .

The logging setting data 42 will be further explained. FIG. 10 shows an example of the data structure of the logging setting data 42. As shown in FIG.

The logging setting data 42 includes project data information 51 , collection operation setting information 52 , and collection target setting information 53 .

The project data information 51 is information specifying a user program to be executed by the PLC 1, and includes information such as the name given to the object code obtained by compiling the user program and the execution date and time of the compilation. Note that the project data information 51 is included as part of the project data 41 .

The collection operation setting information 52 is information created by the collection operation setting process of S120. The collection operation setting information 52 includes, for example, the data collection timing, the collection period, the save timing when the PLC 1 saves the collected data in the external storage device 17, and the external storage device 17 where the collected data is saved. Contains identifying information.

The collection target setting information 53 is information about the target variable selected by the collection target setting process of S110. An example of the data structure of the collection target setting information 53 is shown in FIG.

In the example of FIG. 11, the collection target setting information 53 includes information on the total size of collected data at the data collection timing. The collection target setting information 53 also includes information on the number of target variables that are targets for data collection. Furthermore, the collection target setting information 53 includes information on memory type, data type, memory address, and data size as information about each target variable. These pieces of information specify the locations on the memory 14 of the storage areas used to hold the values of the target variables when the user program is executed in the PLC 1 .

Setting of conditions for execution of logging processing by the PLC 1 is performed by the support device 30 by using the setting tool 40 described above.

<Run logging>

Next, in the PLC system 10 of FIG. 3, the logging process performed by PLC1 according to the conditions set by PC2 as the support apparatus 30 is demonstrated.

First, FIG. 12 will be described. FIG. 12 is a diagram showing an example of the functional configuration of the PLC1. It is assumed that the user presets a control cycle in the PLC 1 when performing the above-described control processing.

In the configuration example shown in FIG. 12 , the PLC 1 includes a process executing section 61 , a ring buffer 62 and a storage section 63 .

As described above, the PLC 1 repeatedly executes the cycle of the input process of S210, the program execution process of S220, the output process of S230, the system process of S240, and the control process of S200 including the logging process of S250. In the functional configuration example shown in FIG. 12, the processing execution unit 61 repeatedly executes the control processing cycle of S200. In the hardware configuration example shown in FIG. 5, this control processing is executed by the CPU 12 .

The ring buffer 62 is a storage area for storing collected data in which the value of the target variable collected by the logging process in S250 is associated with the value of the target variable collected at the collection time each time the value of the target variable is collected. is. In the hardware configuration example shown in FIG. 5, the ring buffer 62 is configured by part of the storage area of the memory 14 .

The logging process of S250 includes a process of determining whether the execution time of one cycle of the control process of S200 falls within a preset control cycle. This logging process further includes a process of interrupting the collection of the values of the target variables in the logging process included in the control process of the cycle for which it is determined that the execution time does not fit within the control cycle. By interrupting the collection of the values of the target variables in such a case, the processing period of the logging process is prevented from prolonging, so that the influence on the execution of the user program and the control of the external device is suppressed.

Note that, as the process of interrupting the collection, for example, the process of discarding from the ring buffer 62 the collected data including the values of the variables collected in the logging process included in the control process of the cycle for which it is determined that the execution time does not fit within the control period. may be included in the logging process.

In the collected data stored by the ring buffer 62, for example, the value of the collection timing counter 64, which counts the number of times the collection time has come, is added to the collection time and the value of the target variable collected at the collection time. It may be associated and included. The value of the collection timing counter 64 makes it possible to recognize that the collection of the value of the target variable has been interrupted when the collection result of the value of the target variable is confirmed later.

The storage unit 63 sequentially reads collected data stored in the ring buffer 62 without being discarded, and stores the collected data in the external storage device 17 . In the hardware configuration example shown in FIG. 5 , the storage device I/F 15 provides the function of the storage unit 63 under the control of the CPU 12 . For example, the processing execution unit 61 provided by the CPU 12 may control the storage device I/F 15 as part of the logging processing.

A logging execution method performed by the PLC 1 having such components will be described in more detail with reference to FIG.

The program execution process of S220 executed in the control process of S200 executes the user program using the input data sent from the external device such as the input/output module 3 and the communication module 4, which is captured in the input process of S210. It is a process to This execution result is output by the output process of S230 for controlling the external device. In the hardware configuration example of FIG. 5, the CPU 12 that executes this program execution process uses the storage area of the memory 14 for executing the user program. The storage area used at this time is called a program use area 14a.

The logging process of S250 executed in the control process of S200 is a process of collecting the values of the aforementioned target variables among the variables used in the user program executed by the program execution process of S220. It is assumed that the logging setting data 42 including the information about the target variables and the operation setting information of the logging process is created in the support device 30 (PC2) as described above and provided to the PLC1 in advance.

The CPU 12 of the PLC 1 performs the time management process of S260 and the collection timing detection process of S270 in parallel with the control process of S200 executed as the process execution unit 61 . The time management process is a process of counting the current time. The collection timing detection process is a process for detecting the arrival of the data collection timing indicated by the collection operation setting information 52 included in the logging setting data 42 .

In the logging process of S250, the process of collecting each value of the target variable is performed in accordance with the detection of the arrival of the collection timing by the collection timing detection process. Also, in the logging process, the collection time of the value is obtained from the time measurement result of the time management process, and the collection data in which the value and the collection time are associated with each other are stored in the ring buffer 62 .

Also, the CPU 12 of the PLC 1 executes the saving process of S280. This saving process includes a process of detecting the arrival of the saving timing indicated by the collection operation setting information 52 included in the logging setting data 42 . Also, in this saving process, the storage device I/F 15 is controlled to read the collected data saved in the ring buffer 62 in response to detection of the arrival of the saving timing, and the collected data indicated by the collecting operation setting information 52 is read out. It includes a process of saving in the external storage device 17, which is the destination of saving.

Here, the logging process of S250 and the saving process of S280 will be described in more detail using the flowchart shown in FIG.

In FIG. 14, the processes of S281 and S282 represent the details of the saving process, and the remaining processes of S251 to S254 and S290 represent the details of the logging process.

The processing shown in FIG. 14 is started when the processing start timing of the logging processing arrives in each cycle of the control processing of S200.

First, in S251, a process of starting measurement of the execution time of the logging process in the current execution cycle of the control process of S200 is performed.

Next, in S252, a process of determining whether or not the arrival of the collection timing is detected by the collection timing detection process of S270 is performed. In this determination process, when it is determined that the arrival of the collection timing has been detected (when the determination result is YES), the collection process of S290 is performed. On the other hand, when it is determined in this determination process that the collection timing has not been detected (when the determination result is NO), the process shown in FIG. 14 ends.

The collection process of S290 is a process of collecting the respective values of the target variables and storing the collected values in the ring buffer 62 as collected data 73, which will be described later. The details of this collection processing will be described later.

Following the process of S290, in S253, a process is performed to determine whether or not the execution time of the current logging process whose measurement was started in the process of S251 is within the maximum processing time described above. This maximum processing time may be calculated in the PLC 1 using a method similar to that performed by the support device 30, for example, based on a preset control cycle. Also, the maximum processing time already calculated by the support device 30 may be included in the logging setting data 42, for example, so that the PLC 1 receives it from the support device 30. FIG.

In the determination process of S253, when it is determined that the execution time of the current logging process is within the maximum processing time (when the determination result is YES), the process proceeds to S281. On the other hand, in the judgment processing of S253, when it is judged that the execution time of the logging processing this time did not fall within the maximum processing time (when the judgment result is NO), the processing proceeds to S254.

In S254, a process of discarding the collected data 73 saved in the ring buffer 62 by the collection process of S290 in the logging process currently being executed is performed, and then the process shown in FIG. 14 ends.

In S281, processing is performed to determine whether or not the save timing indicated by the collection operation setting information 52 included in the logging setting data 42 has arrived. In this determination process, when it is determined that the save timing has arrived (when the determination result is YES), the process proceeds to S282. On the other hand, when it is determined in this determination process that the save timing has not arrived (when the determination result is NO), the process shown in FIG. 14 ends without performing the process of S282.

In S282, the collected data 73 saved in the ring buffer 62 by the collection processing of S290 in the logging processing currently being executed is read out, and the logging collection data 70 is stored in the external storage device 17 of the save destination indicated by the collection operation setting information 52. The process to save as is performed.

The logging collection data 70 will be further explained. FIG. 15 shows an example of the data structure of the logging collection data 70. As shown in FIG.

The logging collection data 70 includes project data information 51 , collection data count 71 , collection data size 72 , and one or more collection data 73 .

The project data information 51 is information that specifies the user program executed by the PLC 1, and includes, for example, the name given to the object code obtained by compiling the user program and information on the execution date and time of the compilation. That is, the project data information 51 included in the logging collection data 70 is the same as the project data information 51 included in the logging setting data 42 . The CPU 12 reads the project data information 51 from the logging setting data 42 and incorporates it into the logging collection data 70 in the collection process of S290.

The collected data count 71 is information representing the number of collected data 73 included in the logging collected data 70 . Also, the collected data size 72 is information representing the total data amount of the collected data 73 included in the logging collected data 70 .

The logging collection data 70 includes, as collection data 73, data on the collected values of the target variables in the order in which the values were collected. An example of the data structure of this collected data 73 is shown in FIG.

In the example of FIG. 16, the collected data 73 includes time stamp information. This timestamp represents the time when the value of the target variable was collected.

The collection data 73 also includes information on the collection timing counter value. The collection timing counter 64 is a counter that counts the number of times of detection by the collection timing detection process of S270 described above, that is, the number of times the collection timing for collecting the value of the target variable has arrived. Therefore, the collection timing counter 64 counts up by one each time the collection timing arrives. In the data structure example of FIG. 15, the collection timing counter value included in the collected data 73 is "1" for "collected data 1", "2" for "collected data 2", and " Collected data N” is assumed to be “N”. The use of this collection timing counter value will be described later.

Further, the collected data 73 includes data representing respective values of the target variables collected at the time of the "timestamp" as "variable data 1", "variable data 2", ..., "variable data N". is

In the process of S282, the logging setting data 42 and the collected data saved in the ring buffer 62 are used to create the logging collected data 70 having such a data structure and save it in the external storage device 17. .

After that, when the process of S282 ends, the process shown in FIG. 14 ends.

It should be noted that when the logging process shown in the flowchart of FIG. 14 is finished, the CPU 12 also performs a process of further saving the logging setting data 42 in the external storage device 17 . This logging setting data 42 is used when collecting data 73 to be described later is displayed.

Next, the collection processing of S290 in FIG. 14 will be described in more detail using the flowchart shown in FIG.

First, in S291, the current time measured by the time management process in S260 described above is obtained as a time stamp, and the obtained time stamp is written in the ring buffer 62 as data at the head position of the collected data 73. will be

Next, in S292, the current count value of the collection timing counter 64, that is, the number of times the collection timing has come is obtained, and the obtained count value is written to the ring buffer 62 following the write position of the time stamp of the collected data 73. is written to.

In S293, the current value of each target variable is acquired, and following the write position of the collection timing counter value of the collection data 73, each acquired value is used as variable data, and a predetermined value associated with each of the target variables is stored. The process of writing to the ring buffer 62 is performed in order.

The value of the target variable is specified based on the information on the memory type, data type, memory address, and data size of the target variable included in the collection target setting information 53 of the logging setting data 42, and is specified in the program use area 14a. held in the upper position. Therefore, in the processing of S293, the value of the target variable is acquired by reading the data held at this position, and the value is written to the ring buffer 62. FIG.

Next, in S294, a process is performed to determine whether or not the execution time of the current logging process whose measurement was started in the process of S251 of FIG. 14 is within the maximum processing time described above. In this determination process, when it is determined that the execution time of the current logging process is within the maximum processing time (when the determination result is YES), the process proceeds to S295. On the other hand, when it is determined in this determination process that the execution time of the logging process of this time did not fall within the maximum processing time (when the determination result is NO), the collection process of this time ends. For the purpose of speeding up the processing, the processing of S294 is performed when it is determined that the values of all target variables have been collected (when the determination result is YES) in the determination processing of S295 described below. You can do it later.

In S295, a process is performed to determine whether or not values of all target variables whose information is included in the collection target setting information 53 of the logging setting data 42 have been collected. In this determination process, when it is determined that the values of all target variables have been collected (when the determination result is YES), the current collection process ends. On the other hand, when it is determined in this determination process that there are still target variables whose values have not been collected yet (when the determination result is NO), the process returns to S293, and the target variables whose values have not been collected are returned to S293. A variable is processed to collect its value.

When the collection process described above is completed, the storage of the collected data 73 in the ring buffer 62 is completed, and then the process of S253 in FIG. 14 is performed.

Next, the use of the collection timing counter value included in the collected data 73 will be described with reference to FIGS. 18 and 19. FIG.

The interrupt processing of S299 shown in FIGS. 18 and 19 is, for example, processing for responding to input/output refresh of the input/output module 3 and message communication from the communication module 4 in the PLC system 10 of FIG. and is a process with a high priority. Depending on the operating conditions of the PLC 1, the logging process within the maximum processing time described above may not be able to collect the values of all the target variables due to the execution of such interrupt processing.

FIG. 18 shows an example in which values of all target variables are collected by logging processing even when such interrupt processing occurs. In the example of FIG. 18, system processing is no longer executed in the control processing of the control cycle in which the interrupt processing of S299 is executed and the values of all target variables are collected and the logging processing of S250 is executed. ing. Therefore, in this control cycle, the operation management of the PLC 1 itself becomes insufficient, and as a result, it is conceivable that the logging process may affect the execution of user programs and the control of external devices.

In order to prevent such a situation, the PLC 1 of this embodiment executes the processes of S253 and S254 in FIG. As a result of this execution, as shown in FIG. 19, if the execution time of the logging process in S250 does not fall within the maximum processing time, the collected data 73 in the ring buffer 62 is discarded and the logging process is interrupted. The execution time of the system processing of S240 is ensured.

The lower part of FIG. 19 shows how the collected data 73 is stored in the ring buffer 62 when the collected data 73 is discarded due to interruption of the logging process. More specifically, "collected data N+1" following "collected data N" is discarded, and by logging processing in the next control period following the control period in which "collected data N+1" was discarded, A situation is shown in which "collected data N+2" is stored.

At this time, “collected data N” and “collected data N+2” are arranged in this order as the collected data 73 in the logging collected data 70 stored in the external storage device 17 . Here, the collection timing counter values included in "collected data N" and "collected data N+2" are respectively "N" and "N+2", and the value of the difference between the two is "2" instead of "1". In this way, by detecting that the difference between the collection timing counter values of the two pieces of collected data 73 consecutively arranged in the logging collected data 70 is greater than 1, the collected data 73 is interrupted by interrupting the logging process. It becomes possible to detect that it has been discarded.

<Display of collected data by logging>

Next, a method of displaying the collected data 73 obtained by the logging process performed by the PLC 1 in the PLC system 10 of FIG. 3 will be described.

First, the hardware configuration of the device that displays the collected data 73 will be described. FIG. 20 shows a hardware configuration example of the collected data display device 80. As shown in FIG.

In the configuration example of FIG. 20, the collected data display device 80 includes a CPU 81, a memory 82, an input device 83, an auxiliary storage device 84, a display device 85, and a storage device I/F86. All of these components are connected to the internal bus 87 and can exchange data with each other.

The CPU 81, for example, by executing a predetermined program using the memory 82, provides a function of controlling various displays such as display of collected data, waveform display of collected data, display of indefinite values when data is missing, and the like. .

The input device 83 is, for example, a keyboard, a pointing device, or the like, and is used to input instructions or information from the user.

The auxiliary storage device 84 is a magnetic disk device, an optical disk device, a magneto-optical disk device, or the like, and may be, for example, a hard disk drive or a flash memory. The collected data display device 80 can store programs and data in the auxiliary storage device 84 and load them into the memory 82 for use.

The display device 85 is used, for example, for making inquiries or instructions to the user and for displaying and outputting processing results.

The storage device I/F 86 manages reading processing of various data from the external storage device 17 such as a memory card.

The collected data display device 80 has the above hardware configuration. Since such a hardware configuration is a standard configuration that a general computer has, the collected data display device 80 may be configured using such a computer. Further, the collected data display device 80 may be configured by further using the PC 2 functioning as the support device 30 in the PLC system 10 of FIG.

Next, FIG. 21 will be described. FIG. 21 is a diagram showing a functional configuration example of the collected data display device 80. As shown in FIG.

In FIG. 21, it is assumed that the logging collection data 70 described above is stored in the external storage device 17 by the PLC 1 . As described with reference to FIGS. 15 and 16, the logging collection data 70 includes the values of the target variables collected by the logging process of S250 executed by the PLC 1, and the collection times of the values of the target variables. Data 73 are arranged in the order of collection time. The collected data 73 also includes the value of the collection timing counter 64 that counts the number of times the collection time has come, in association with the collection time and the value of the target variable collected at the collection time. there is

In the configuration example of FIG. 21 , the collected data display device 80 includes a reading section 91 , a display section 92 and a display control section 93 .

The reading unit 91 reads the logging collection data 70 from the external storage device 17 .

Based on the logging collection data 70 read from the external storage device 17, the display unit 92 displays the collection time and the values of the target variables collected at the collection time in association with each other.

When the display control unit 93 finds traces of interruption of the logging process from the logging collection data 70 read out from the external storage device 17, the display control unit 93 causes the display unit 92 to further display a display indicating that the value of the target variable is missing due to the interruption. . In the display indicating this loss, the value of the missing target variable is displayed in association with the collection time at which it was collected by the logging process. Note that the display control unit 93 displays, for example, a display indicating that the value of the target variable is an indeterminate value as a display indicating the missing value of the target variable. It may be displayed on the display unit 92 in association with the time.

By displaying such a missing value of the target variable, it is possible to make the user aware that the logging process has been interrupted. In addition, by allowing missing values in the display of the values of the target variables, it becomes possible to cause the PLC 1 to perform logging within a range that does not affect the execution of user applications and the control of devices.

For example, the display control unit 93 can display data based on the difference between the values of the collection timing counter 64 included in each of the two pieces of collected data 73 consecutively arranged in the collected logging data 70 read from the external storage device 17. , may find traces of the interruption.

An example of a method of displaying collected data performed by the collected data display device 80 having such a configuration will be described in more detail with reference to FIG. 22 .

The collected data display device 80 performs program display processing in S310, waveform display processing in S320, logging file analysis/conversion processing in S330, and display control processing in S340. A program that causes the CPU 81 to perform each of these processes is sometimes called engineering software.

The program display process of S310 displays the user program included in the project data 41 described above, and uses the collected data 73 included in the logging collection data 70 to display the values of the target variables for the user program. processing. It is assumed here that the project data 41 has already been created by the user by executing a predetermined project data editing program on the PC 2, for example, and is already stored in the auxiliary storage device 84, for example.

The waveform display process of S320 is a process of displaying the relationship between the collection time and the value of the target variable using the collected data 73 included in the logging collected data 70 in waveform.

The logging file analysis/conversion process of S330 analyzes the logging setting data 42 and the logging collected data 70, and converts the collected data 73 into input data for the program display process of S310 and the waveform display process of S320. is. Here, it is assumed that the logging setting data 42 and logging collection data 70 are provided by the external storage device 17 . These data are read from the external storage device 17 and used in the logging file analysis/conversion process.

The display control process of S340 includes a process of providing the value of the target variable associated with the collection timing obtained by the logging file analysis/conversion process of S330 to the program display process of S310 and the waveform display process of S320. . Further, the display control processing includes processing for interlocking the display of the program display processing and the waveform display processing.

Details of each process shown in FIG. 22 performed by the collected data display device 80 will be further described below.

First, the details of the program display processing of S310 will be described with reference to FIG.

As shown in FIG. 23, the program display process of S310 includes an operation UI process of S311, a target variable value display control process of S312, and a user program display process of S313.

The operation UI process of S311 is a process of receiving an input corresponding to an operation on the input device 83 by the user of the collected data display device 80. FIG.

The target variable value display control process of S312 is a process of receiving the input information accepted by the operation UI process of S311 and the linked information from the display control process of S340, and controlling the display of the value of the target variable. .

The user program display processing of S313 displays the user program included in the project data 41, and displays the value of the target variable on the display of the user program under the control of the target variable value display control processing of S312. is.

FIG. 24 will now be described. FIG. 24 is a first example of a display screen of collected data. This display screen is displayed on the display device 85 by the CPU 81 executing the program display process of S310.

The screen example of FIG. 24 shows a state in which the UI screen 120 obtained by the operation UI process of S311 is displayed over the user program display screen 110 obtained by the user program display process of S313.

A diagram (for example, a ladder program) representing the contents of the user program included in the project data 41 is created by the user program display processing of S313 and displayed as the user program display screen 110 .

The UI screen 120 includes a frame advance button 121 and a seek bar 122 that give an instruction to sequentially update the display of the values of the target variables collected at each collection timing, and the time of the collection timing of the values of the target variables to be displayed. It has a time input field 123 and the like. The time input field 123 also has a function as a display field for displaying the time of collection timing designated by operating the frame advance button 121 or the seek bar 122 .

By the operation UI processing of S<b>311 , the collection timing specified according to the operation of the frame advance button 121 or the seek bar 122 is acquired, and the time of this timing is displayed in the time input field 123 . Further, when a time input operation is performed in the time input field 123, the input time is acquired as the designated collection timing by this operation UI processing.

By the target variable value display control processing of S312, the value of the target variable associated with the collection timing in the logging collection data 70 and the specification of the collection timing obtained by the operation UI processing of S311 are acquired. The logging collection data 70 is acquired by the logging file analysis/conversion processing of S330 and sent to the display control processing of S340. receive. Further, by this target variable value display control processing, the value of the target variable at the specified collection timing is sent to the user program display processing of S313, and by the user program display processing, the display of the value of the target variable is displayed by the user program. This is done on the display screen 110 .

In the screen example of FIG. 24, the ON/OFF display 111 and the variable display 112 display the values of the target variables.

The ON/OFF display 111 displays the element in a different color depending on the state indicated by the value of the variable when the state of the program component having either ON or OFF is selected as the target variable. is filled in to represent the variable value. In the screen example of FIG. 24, as the ON/OFF display 111, the elements to be collected in the user program are displayed in black. , "OFF", the element is displayed in blue.

The variable display 112 directly displays the numerical value as the variable value when the numerical value related to the program component is selected as the target variable.

As described above, through the processes of S311, S312, and S313, the collection time and the values of the target variables collected at the collection time are associated with each other, as shown in the screen example of FIG. 85.

The program display process of S310 further includes a verification process of S314 and a warning process of S315.

The matching process of S314 is a process of matching the project data 41, the logging setting data 42, and the logging collection data 70 with the project data information 51. FIG.

The warning process of S315 is a process of giving a predetermined warning when the project data information 51 of each data does not match by the matching process of S314.

FIG. 25 shows an example of a warning screen displayed on the display device 85. As shown in FIG. The predetermined warning by the warning process of S315 is performed by displaying such a warning screen on the display device 85, for example. This screen example includes a warning dialog 130 that warns the user that the project data information 51 does not match. It should be noted that the function of displaying the value of the target variable can be used in the collected data display device 80 even if the project data information 51 does not match, because it is useful when debugging a user program, for example.

Next, details of the waveform display processing in S320 will be described with reference to FIG.

As shown in FIG. 26, the waveform display process of S320 includes the operation UI process of S321, the target variable value display control process of S322, and the waveform creation process of S323.

The operation UI process of S321 is the same process as the process of S311, and is a process of receiving an input according to the operation of the input device 83 by the user of the collected data display device 80. FIG.

The target variable value display control process of S322 is the same process as the process of S312. This is processing for controlling the display of the value of the target variable.

The waveform creation processing of S323 creates a waveform representing the relationship between the collection timing and the target variable based on the value of the target variable associated with the collection timing provided by the display control processing of S340. This is the process of displaying

FIG. 27 will now be described. FIG. 27 is a first example of the waveform display screen 140 of acquired data. This waveform display screen 140 is displayed on the display device 85 by the CPU 81 executing the waveform display processing of S320.

A waveform 141 included in the waveform display screen 140 is created by the waveform creating process of S323. In the screen example of FIG. 27, the waveforms 141 for each of "variable 1," "variable 2," and "variable 3" are displayed using solid lines, broken lines, and dashed-dotted lines, respectively. A time display 142 included in the waveform display screen 140 represents collection timings in which the relationship with the variable value is represented by the waveform 141, and is displayed on the waveform display screen 140 by the waveform generation processing in S323. .

Further, when an instruction to move the collection timing range is accepted by the operation UI processing of S321, the waveform 141 for the collection timing range after movement is displayed on the waveform display screen 140 by the waveform creation processing of S323. Also, the time of the acquisition timing indicated by the thick line 143 displayed on the waveform display screen 140 is displayed in the time display field 144 by the waveform generation process of S323.

By the target variable value display control process of S322, the value of the target variable associated with the collection timing in the logging collection data 70 provided by the display control process of S340 is acquired. In addition, the time of the collection timing displayed in the time display field 144 is obtained by the target variable value display control processing of S322. Furthermore, by this target variable value display control processing, the value of the target variable at the acquired collection timing is displayed in the variable value display field 145 as the value of the target variable represented by the position of the intersection of the waveform 141 and the thick line 143. be done.

As described above, through the processes of S321, S322, and S323, the collection time and the values of the target variables collected at the collection time are associated with each other, as shown in the screen example of FIG. 85.

Next, details of the logging file analysis/conversion process of S330 will be described using FIG.

As shown in FIG. 28, the logging file analysis/conversion process of S330 includes the logging setting data acquisition process of S331, the logging collection data acquisition process of S332, the collected data loss judgment process of S333, and the display data of S334. Includes data preparation process.

The logging setting data acquisition process of S<b>331 is a process of loading the logging setting data 42 from the external storage device 17 .

The logging collection data acquisition process of S332 is a process of reading and capturing the logging collection data 70 from the external storage device 17, and is a process of providing the function of the reading unit 91 in the functional configuration example shown in FIG.

The collected data loss determination process of S333 is a process of finding traces of interruption of the logging process from the logging collected data 70 read out from the external storage device 17 . More specifically, in this collected data loss determination process, the collected data 73 is lost by referring to the collected data 73 included in the logging collected data 70 acquired by the logging collected data acquisition process of S332. This is the process of determining whether or not

In the display data creation processing of S334, when it is determined that there is a loss by the collected data loss determination processing of S333, the value of the object variable whose value is an indefinite value is used as data instead of the missing collected data 73. This is a process of creating missing display data indicating that there is a missing image.

Next, FIG. 29 will be described. FIG. 29 is a flow chart showing the processing contents of the logging file analysis/conversion processing of S330.

In FIG. 29, first, in S401, the logging setting data 42 and the logging collection data 70 are read from the external storage device 17 and imported. This process corresponds to the logging setting data acquisition process of S331 and the logging collection data acquisition process of S332 in FIG.

The subsequent processes of S402 and S403 are processes for detecting that the collected data 73 has been discarded due to interruption of the logging process, described using FIGS. 18 and 19, using the collection timing counter value. The processes of S402 and S403 correspond to the collected data loss determination process of S333 in FIG.

First, in S402, one collection data 73 included in the order described above is extracted from the logging collection data 70, and the difference in the collection timing counter value between the collection data 73 and the collection data 73 in the previous order is calculated. A process of calculating the value is performed. That is, in S402, the process of calculating the difference value between the values of the collection timing counter 64 included in each of the two collection data 73 consecutively arranged in the logging collection data 70 is performed. Note that if the collected data 73 that is taken out is the leading data in the collected logging data 70, the difference value is set to "1".

Next, in S403, a process of determining whether or not the difference value calculated in the process of S402 is 2 or more (that is, whether or not it is not 1) is performed. In this determination process, when it is determined that the difference value is 2 or more (when the determination result is YES), it is determined that the collected data 73 is discarded and missing, and that traces of interruption of the logging process have been found. Then, the process proceeds to S404. On the other hand, in this determination process, when it is determined that the difference value is not 2 or more (when the determination result is NO), the process proceeds to S405 without executing the process of S404.

In S404, the aforementioned missing display data is created as data in place of the missing collected data 73, and in the logging collected data 70, the collected data 73 extracted in the processing of S402 and the collected data 73 in the previous order are combined. Insertion processing is performed between

The number of missing display data created by the process of S404 is one less than the difference value calculated by the process of S402. Also, the data structure of the generated missing display data is the same as that of the collected data 73 shown in FIG. 16, and data indicating an indefinite value (for example, null data) is arranged in the missing display data as each value of the target variable. do.

The time stamp information and the collection timing counter value information in the missing display data created by the process of S404 contain their respective estimated values. That is, the time stamp information includes information about the estimated time when the value of the target variable that should have been included in the missing collected data 73 was collected. In addition, information on the collection timing counter value that is presumed to have been included in the missing collection data 73 is included in the information on the collection timing counter value. These estimated values are, for example, values obtained by linearly interpolating values included in each of the collected data 73 before and after the missing display data is inserted.

The processing of S404 described above corresponds to the display data creation processing of S334 in FIG.

In S405, a process of incrementing (increase by 1) the value of the collected data number count that counts the number of times the collected data 73 is taken out by the process of S402 is performed.

In S<b>406 , processing is performed to determine whether or not the current value of the collected data number count has reached the value indicated by the collected data number 71 included in the logging collected data 70 . In this determination process, when it is determined that the value of the collected data number count has reached the value indicated by the collected data number 71 (when the determination result is YES), this logging file analysis/conversion process is terminated. . On the other hand, when it is determined in this determination process that the value of the collected data number count has not yet reached the value indicated by the collected data number 71 (when the determination result is NO), the process proceeds to S402. return. At this time, the remaining collected data 73 that has not yet been extracted from the logging collected data 70 is processed after S402.

The above processing is the logging file analysis/conversion processing of S330.

Next, details of the display control processing of S340 will be described using FIG.

As shown in FIG. 30, the display control process of S340 includes the variable value provision process of S341, the reproduction control process of S342, and the collected data acquisition process of S343.

In the variable value provision process of S341, the logging collection data 70 obtained by the logging file analysis/conversion process of S330 is used as the value of the target variable associated with the collection timing, and the program display process of S310 and the waveform display of S320 are performed. It is the processing provided to the processing. Note that the provided logging collection data 70 may include missing display data created by logging file analysis/conversion processing.

The reproduction control process of S342 is a process of controlling the program display process of S310 and the waveform display process of S320 when a predetermined interlocking instruction is received, and interlocking the contents of the screen displayed by each process. By this playback control processing, for example, processing is performed to set the collection timing designated by the operation on the UI screen 120 in the screen example of FIG. 24 and the collection timing indicated by the thick line 143 in the screen example of FIG. 27 to be the same time. will be

The collected data acquisition process of S343 is a process of acquiring the logging collection data 70 obtained by the logging file analysis/conversion process of S330 and providing it to the variable value provision process of S341.

As described above, the display control process of S340 provides the logging collection data 70 obtained by the logging file analysis/conversion process of S330 to the program display process of S310 and the waveform display process of S320. The logging collection data 70 provided at this time may include the above-described missing display data. Next, screens displayed on the display device 85 by the program display process and the waveform display process in this case will be described.

First, FIG. 31 will be described. FIG. 31 shows a second example of the display screen of the collected data. When traces of interruption of the logging process are found, the user program display screen 110 displays a display indicating the loss of the value of the target variable due to the interruption. Included is an example screen.

As can be seen by comparing the screen example of FIG. 31 with the screen example of FIG. 24, in the screen example of FIG. included in This ON/OFF undefined display 113 indicates that the state of a program component having either ON or OFF state is selected as a target variable and that the value of the target variable is an undefined value. It is a display when it is indicated by the collected data 70 .

In addition, in the screen example of FIG. 31, the user program display screen 110 includes a display of "??" This variable undefined value display 114 is displayed when a numeric value related to a program component is selected as a target variable and the logging collection data 70 indicates that the value of the target variable is an undefined value. .

If the logging collection data 70 includes missing display data associated with the collection timing acquired by the operation UI processing of S311, the ON/OFF indefinite display 113 and variable indefinite value display 114 are displayed by the user program. It is displayed on the display screen 110 . This display is performed by the user program display processing of S313.

Next, FIG. 32 will be described. FIG. 32 shows a second example of the waveform display screen 140 of the collected data. When traces of interruption of the logging process are found, the waveform display screen 140 shows the loss of the value of the target variable due to the interruption. This is an example screen included in

As can be seen by comparing the screen example of FIG. 32 with the screen example of FIG. 27, in the screen example of FIG. Included in display screen 140 . This waveform indeterminate display 146 is displayed when the logging collection data 70 indicates that the value of the selected target variable is indeterminate.

When the missing display data is included in the logging collection data 70 , such waveform indefinite display 146 is displayed instead of the waveform 141 at a position corresponding to the collection timing on the waveform display screen 140 . This display is created by the waveform creating process of S323.

As described above, the program control process of S310 and the waveform display process of S320 provide the function of the display unit 92 in the functional configuration example shown in FIG. Also, the function of the display control unit 93 in the functional configuration example shown in FIG. 21 is provided by the logging file analysis/conversion process of S330 and the display control process of S340. As a result, the collected data display device 80 displays the values of the target variables collected by the logging process, including the display indicating the missing values of the target variables.

While the disclosed embodiments and their advantages have been described in detail above, those skilled in the art can make various modifications, additions, and omissions without departing from the scope of the invention, which is clearly defined in the appended claims. Will.

1 PLC
2 PCs
3 input/output module 4 communication module 6 communication cable 7 communication bus 10 PLC system 11, 26 communication I/F
12, 21, 81 CPUs
13 Bus controller 14, 22, 82 Memory 14a Program use area 15, 86 Storage device I/F
16, 27, 87 internal bus 17 external storage device 23, 83 input device 24, 85 display device 25, 84 auxiliary storage device 30 support device 31 program analysis unit 32 selection unit 33 first output unit 34 second output unit 40 setting tool 41 project data 42 logging setting data 51 project data information 52 collection operation setting information 53 collection target setting information 61 process execution unit 62 ring buffer 63 storage unit 64 collection timing counter 70 logging collection data 71 number of collection data 72 collection data size 73 collection data 80 Collected data display device 91 Reading unit 92 Display unit 93 Display control unit 100, 120 UI screen 101 Program selection unit 102 Extraction variable display unit 103 Target variable display unit 104 Registration button 105 Release button 106 Batch registration button 107 Batch release button 108 Collection Data size display part 109 Estimated control cycle display part 110 User program display screen 111 ON/OFF display 112 Variable display 113 ON/OFF undefined display 114 Variable undefined value display 120 UI screen 121 Frame advance button 122 Seek bar 123 Time input field 130 Warning dialog 140 Waveform display screen 141 Waveform 142 Time display 143 Thick line 144 Time display field 145 Variable value display field 146 Waveform indefinite display

Claims (11)

A programmable logic controller,
An input process for fetching input data sent from an external device, a program execution process for executing a user application program using the input data, an output process for outputting the execution result of the user application program and controlling the external device, a processing execution unit that repeatedly executes control processing cycles including system processing that manages the operation of the programmable logic controller itself and logging processing that collects the values of variables used in the user application program ;
a ring buffer for storing collected data in which the values of the variables collected by the logging process and the values of the variables collected at the collection times are associated each time the values of the variables are collected;
The logging process determines whether or not the execution time of one cycle of the control process falls within a preset control cycle, and controls the cycle for which it is determined that the execution time does not fall within the control cycle. In the logging process included in the process, as a process of interrupting the collection of the values of the variables, the collected in the logging process included in the control process of the cycle determined that the execution time does not fit within the control cycle Discarding the collected data, including variable values, from the ring buffer ;
A programmable logic controller characterized by: The collected data includes a value of a collection timing counter that counts the number of times the collection time has come, in association with the collection time and the value of the variable collected at the collection time. 2. The programmable logic controller of claim 1 . 3. The programmable logic controller according to claim 2 , further comprising a storage unit that sequentially reads the collected data stored in the ring buffer without being discarded and stores the collected data in an external storage device. A programmable logic controller, comprising input processing for fetching input data sent from an external device, program execution processing for executing a user application program using the input data, and outputting the execution result of the user application program to an external device output processing for controlling the programmable logic controller, system processing for managing the operation of the programmable logic controller itself, and logging processing for collecting the values of variables used in the user application program. A support device for a logic controller, comprising:
a program analysis unit that analyzes the user application program and extracts variables used in the user application program;
a selection unit that selects, as a target variable, a variable to be collected by the logging process from among the variables extracted by the program analysis unit;
a first output unit that outputs information specifying the target variable as logging setting data for the programmable logic controller;
determining whether the execution time of one cycle of the control process when the logging process is executed for all the target variables selected by the selection unit falls within a preset control cycle; When the execution time of does not fall within the control cycle, caution information is output , and one cycle of the control process is executed when the logging process is executed for all of the target variables selected by the selection unit a second output unit that further outputs the time estimated to be required for the estimated control period as an estimated control period ;
A support device comprising: The logging setting data is a storage area on a memory provided in the programmable logic controller as information specifying the target variable, and is a storage area of the target variable when the user application program is executed in the programmable logic controller. 5. The support device according to claim 4 , further comprising information specifying a location on said memory of said storage area used for holding the value of . A programmable logic controller, comprising input processing for fetching input data sent from an external device, program execution processing for executing a user application program using the input data, and outputting the execution result of the user application program to an external device output processing for controlling the programmable logic controller, system processing for managing the operation of the programmable logic controller itself, and logging processing for collecting the values of variables used in the user application program. A display device that displays the values of the variables collected by the logging process by the logic controller,
logging collected data in which collected data in which the values of the variables collected by the logging process are associated with collection times of the values of the variables are arranged in the order of the collection times, and stored in an external storage device by the programmable logic controller; a reading unit that reads the saved logging collection data from the external storage device;
a display unit for displaying the collection time and the value of the variable in association with each other based on the logging collection data read from the external storage device;
When traces of interruption of the logging process are found from the logging collection data read from the external storage device, a display indicating loss of the value of the variable due to the interruption is displayed. a display control unit that further displays on the display unit in association with the collection time collected by
A display device comprising: For each of the collected data arranged in the collected logging data, the value of a collection timing counter that counts the number of times the collection time has come is the value of the collection time and the value of the variable collected at the collection time. contains associated with
The display control unit performs the logging process based on the difference value between the values of the collection timing counters included in each of the two pieces of collected data that are consecutively arranged in the collected logging data read from the external storage device. discover traces of interruptions in
7. The display device according to claim 6 , wherein: The display control unit displays a display indicating that the value of the variable is an indefinite value as a display indicating the missing value of the variable at the collection time when the missing value of the variable is collected by the logging process. 8. The display device according to claim 6 or 7 , characterized in that it is associated with and displayed on the display unit. A programmable logic controller
An input process for fetching input data sent from an external device, a program execution process for executing a user application program using the input data, an output process for outputting the execution result of the user application program and controlling the external device, Repeatedly executing a cycle of control processing including system processing for managing the operation of the programmable logic controller itself and logging processing for collecting values of variables used in the user application program,
Collected data in which the values of the variables collected by the logging process and the values of the variables collected at the collection times are associated with each other are stored in a ring buffer provided in the programmable logic controller each time the values of the variables are collected. save and
In the execution of the logging process, it is determined whether or not the execution time of one cycle of the control process falls within a preset control cycle, and control of the cycle in which it is determined that the execution time does not fall within the control cycle In the logging process included in the process, as a process of interrupting the collection of the values of the variables, the collected in the logging process included in the control process of the cycle determined that the execution time does not fit within the control cycle performing a process of discarding the collected data, including variable values, from the ring buffer ;
A logging method characterized by: A programmable logic controller, comprising input processing for fetching input data sent from an external device, program execution processing for executing a user application program using the input data, and outputting the execution result of the user application program to an external device output processing for controlling the programmable logic controller, system processing for managing the operation of the programmable logic controller itself, and logging processing for collecting the values of variables used in the user application program. A support method performed by a support device for a logic controller,
parsing the user application program to extract variables used in the user application program;
Selecting a variable to be collected by the logging process from among the extracted variables as a target variable;
outputting information specifying the target variable as logging setting data for the programmable logic controller;
Determining whether the execution time of one cycle of the control process when the logging process is executed for all of the selected target variables falls within a preset control cycle,
When the execution time of the control process does not fall within the control cycle, outputting caution information, and performing one cycle of the control process when the logging process is executed for all of the selected target variables Further output the time estimated to be required as an estimated control period ,
A support method characterized by: A programmable logic controller, comprising input processing for fetching input data sent from an external device, program execution processing for executing a user application program using the input data, and outputting the execution result of the user application program to an external device output processing for controlling the programmable logic controller, system processing for managing the operation of the programmable logic controller itself, and logging processing for collecting the values of variables used in the user application program. A display method performed by a display device that displays the values of the variables collected by the logging process by the logic controller,
logging collected data in which collected data in which the values of the variables collected by the logging process are associated with collection times of the values of the variables are arranged in the order of the collection times, and stored in an external storage device by the programmable logic controller; reading the saved logging collection data from the external storage device;
displaying the collection time and the value of the variable in association with each other based on the logging collection data read from the external storage device;
When traces of interruption of the logging process are found from the logging collection data read from the external storage device, a display indicating loss of the value of the variable due to the interruption is displayed. Further display in association with the collection time collected by
A display method characterized by:

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