JP2008084027A - Programmable display device, display program and recording medium recording the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To display the simple constitution of a ladder program performed in the past on a programmable display device having no PLC control function. <P>SOLUTION: A data logging part 212 successively writes device data acquired from a PLC 3 in a logging memory 14 in time series. The logging memory 14 is a memory in the programmable display device 2 or a memory card or a USB memory detachably installed in the programmable display device 2. In the case of displaying an execution state of a ladder program being performed at present on a monitor, a communication switching part 213a provides the device data acquired from the PLC 3 to a ladder monitor part 213. In the case of reproducing and displaying a performance state of a ladder program performed in the past, the communication switching part 213a provides device data read from the logging memory 14 by the data logging part 212 to the ladder monitor part 213. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an improvement of a programmable display that monitors the execution status of a control program that defines a control procedure.

  A control device called a programmable logic controller (hereinafter referred to as “PLC”) manages the control of the target system and the hardware part centering on the CPU and memory in order to realize various controls including sequence control. Software part. The software part includes design of a sequence control flow for operating the PLC in accordance with the control system at the time of design, conversion of the control flow into an instruction word, writing of the instruction word into a memory, and the like. In general, this series of operations is called programming.

  In such programming, a unique language such as a ladder program is used so that it is easy to create a program without having specialized knowledge of computers. It has been developed. For example, a ladder diagram (LD) is a programming language that has been widely used since the ladder circuit can be designed relatively easily using a relay symbol, and is still the most commonly used programming language. Programming software such as a ladder editor has become widespread as a programming tool used in such programming work using a programming language. This software can easily create and edit a program in a form including a symbolized instruction such as a ladder diagram in a computer device such as a personal computer.

  The created program is usually completed by being modified or changed by debugging in order to operate correctly as originally designed. In debugging, the program is executed with the device connected to the PLC to check whether the device is operating as designed. For example, a ladder monitor system is known as a method for confirming how a ladder program is executed (Patent Document 1).

  Such a system is configured to display the execution status of a ladder program on a monitor screen using a display function of the display in a display (programmable display) having a PLC control function.

Further, a system for analyzing a problem that occurs during execution of a ladder program is also disclosed (Patent Document 2). In this system, device data obtained by executing a ladder program is accumulated, and a past execution state of the ladder program is reproduced based on the accumulated data.
Japanese Unexamined Patent Publication No. 2000-20113 (published on January 21, 2000) JP 2003-76405 A (published March 14, 2003)

However, as described above, the system described in Patent Document 1 is configured to display the execution status of the ladder program on a display device having a PLC control function. For this reason, in the above system, it is impossible to carry out the ladder monitor a general indicator does not have the control function in the PLC.

  On the other hand, the system described in the cited document 2 accumulates device data in the programmable display, but it is connected to the programmable display via a network to reproduce the past execution status of the ladder program. It is a personal computer. For this reason, the scale of the system tends to increase.

  The present invention has been made in view of the above problems, and its purpose is to display the execution status of a ladder program executed in the past in a programmable display having no PLC control function with a simple configuration. It is in.

  In order to solve the above-described problem, a programmable display according to the present invention is connected to a control device that controls a device according to a sequence program so as to be communicable, and device data that is updated by executing the sequence program is stored. Data acquisition means for acquiring, data storage device for storing the device data, and data writing / reading means for writing the device data acquired by the data acquisition means to the data storage device and reading from the data storage device A programmable display comprising: a program acquisition means for acquiring the sequence program from the control device; a program storage device for storing the sequence program; and the sequence program acquired by the program acquisition means. Program write / read means for writing to and reading from the program storage device, and read by the program write / read means based on the device data read by the data write / read means And an execution status display means for displaying the execution status of the sequence program.

  In the above configuration, when the control device is executing the sequence program, the device data obtained along with the execution of the sequence program is acquired from the control device by the data acquisition means, and further the data writing / reading means Is written to the data storage device. Thus, device data obtained as a result of the execution of the sequence program is accumulated in the storage device. The sequence program is acquired from the control device by the program acquisition means, and is further stored in the program storage device by the program writing / reading means.

  When reproducing the execution status of a sequence program that has already been executed, the sequence program is read from the program storage device by the program writing / reading means, and the device data is read from the data storage device by the data writing / reading means. Then, the execution status of the sequence program is reproduced and displayed by the execution status display means based on the read device data. Thereby, the execution status of the sequence program executed in the past is reproduced and displayed on the programmable display.

  The programmable display device includes the device data acquired by the data acquisition unit or the data storage device as the device data based on which the execution status display unit displays the execution status of the sequence program. It is preferable that a device data selection unit that selects any one of the device data read by the loading / reading unit is provided.

  In this configuration, when the device data acquired by the data acquisition unit from the control device is selected by the device data selection unit, the execution status of the currently executed sequence program is displayed by the execution status display unit based on the device data. Is displayed. On the other hand, when the device data read by the data writing / reading means from the data storage device is selected by the device data selecting means, the execution status of the sequence program executed in the past based on the device data is the execution status. Displayed by display means. As described above, when the device data from the control device or the data storage device is selected by the device data selection means, the execution status of the sequence program that is currently executed and the sequence program that has been executed in the past is displayed on the programmable display. Can be displayed.

  The display program of the present invention is a display program for operating any one of the programmable displays described above, and causes a computer to function as each means. The display program is provided by being recorded on a computer-readable recording medium. As a result, the execution status of the sequence program executed in the past is reproduced and displayed in the same manner as the programmable display.

  As described above, the programmable display according to the present invention includes a program acquisition unit that acquires a sequence program from a control device, a program storage device that stores the sequence program, and the sequence program acquired by the program acquisition unit. Based on the device data read by the program writing / reading means and the data writing / reading means that are written to and read from the program storage device, the program writing / reading means reads the program storage device. And an execution status display means for displaying the execution status of the sequence program. Thereby, the execution status of the sequence program executed in the past is reproduced and displayed on the programmable display. Therefore, it is possible to reproduce and display the execution status of a sequence program executed in the past with a simple configuration without adopting a system configuration that is connected to other devices via a network.

  One embodiment of the present invention will be described with reference to FIGS. 1 to 4 as follows.

  As shown in FIG. 1, the control system 1 according to the present embodiment includes a programmable display 2, a PLC 3, and a target system 4.

  The PLC 3 operates in accordance with a sequence program (such as a ladder program) that defines a control procedure created by the user. The PLC 3 fetches the state of the input device 5 via the input unit and gives a control instruction to the output device 5 at every predetermined scan time such as several tens of ms, for example.

  As the input device 5, devices such as sensors (temperature sensors, optical sensors, etc.) and switches (push button switches, limit switches, pressure switches, etc.) are used. As the output device 5, an actuator, a relay, a solenoid valve, a display, or the like is used. These devices 5 are arranged in required parts of various target systems 4 such as a production line and constitute a part of the control system 1.

  The device 5 may be a specific area in a data memory (not shown) for storing data manually input from an input device such as the touch panel 25 described later. The device 5 may be a specific area in the memory in the PLC 3.

  The memory (device memory) in the PLC 3 stores data (word data or bit data) indicating the state of the device 5 (output value from the device 5 or set value to the device 5) in an area specified by the device address. is doing. In the memory, a word device and a bit device are set. The word device is set as an area for storing word data such as numeric values as input / output data, and is designated by a word address (device address). The bit device is set as an area for storing bit data such as an on / off state, and is set by a bit address (device address). With such a setting, the device 5 can be controlled only by accessing an arbitrary word device or bit device in the memory by specifying the device address, or information regarding the state can be individually taken out.

  In the following description, the device address is appropriately referred to as an address.

  The programmable display 2 is provided with an arithmetic processing unit such as a CPU, and is a dedicated computer that realizes an operation function and a display function unique to the programmable display by displaying input operation and display screen data created by the user. is there. The programmable display 2 that is preferably used as an HMI device of the control system 1 is an operation for displaying the state of the device 5 on the screen based on the screen data determined by combining processing definition information (tag) described later. The operation for controlling the state of the device 5 according to the operation on the screen is specified.

  This programmable display 2 acquires the state of each device 5 displayed on the display screen via the PLC 3 by communicating with the PLC 3 via the serial cable 6. For example, the state of each device 5 is displayed on the display 24 described later. It has a function to display. The programmable display 2 has a function of instructing the device 5 to control the state of the device in response to an operation on the touch panel 25 described later.

  The acquisition / change of the state of the device 5 may be instructed each time, or a temporary memory space is prepared in the programmable display 2, and when acquiring / changing, the memory space is accessed and a predetermined It is also possible to communicate with the PLC 3 at every time interval or every predetermined event to synchronize with the entity to which each address is assigned.

  In order to realize the above functions, the programmable display 2 has an HMI control unit 21, a data memory 22, a work memory 23, a display 24, a touch panel 25, and an interface unit (I / F in the figure) 26. , 27, a memory card interface unit (memory card I / F in the figure) 28, and a USB interface part (USB I / F in the figure) 29. Hereinafter, each main part of the programmable display device 2 will be described in detail.

  As the display 24, a flat panel display such as a liquid crystal display, an EL display, or a plasma display is preferably used in order to make the programmable display device 2 thin. The touch panel 25 is an input device provided for performing touch input on the display screen of the display 24.

  The interface unit 26 is a communication control unit for the programmable display 2 to communicate with network devices such as the FTP server 13, and is connected to the network 7. The interface unit 26 is configured to be able to perform network communication based on the IP address of the FTP server 13 or the like.

  On the other hand, the interface unit 27 is a communication control unit for the programmable display 2 to perform serial communication with the PLC 3, and each is connected by a serial cable 6. Further, the interface unit 27 includes the same number of communication ports as the number of connectable PLCs 3 so that a plurality of PLCs 3 can be connected. Here, the correspondence relationship between the manufacturer and model name of the PLC 3 and the communication port to which the PLC 3 is connected is set in advance as connected device data by the user. Moreover, according to the communication port to be connected, PLC3 is given a connected device name such as PLC-A, PLC-B, PLC-C,..., And this connected device name is also added to the connected device data. included. Reading / writing data to / from the PLC 3 bit device and word device as described above is performed by designating the connected device name together with the address.

  The interface unit 27 performs communication using a communication protocol corresponding to the manufacturer and model of the PLC 3 based on the connected device data. The connected device data and the communication protocol are stored in, for example, a data memory 22 described below.

  The memory card interface unit 28 is a reader / writer that writes and reads data to and from the memory card 11 as a storage device. As the memory card 11, a small and large-capacity CF (registered trademark) card is suitable. The USB interface unit 29 is an interface for performing communication with a USB (Universal Serial Bus) device connected to the outside. A USB memory 12 as a storage device is connected to the USB interface unit 29. The memory card 11 and the USB memory 12 described above function as a logging memory 14 (see FIG. 3) described later that logs device data from the PLC 3.

  The data memory 22 is a memory for storing data related to display and communication such as a project file, the above communication protocol, a ladder monitor file, and a capture file, and FEPROM (Flash Erasable and Programmable ROM) is used. Since FEPROM is a rewritable read-only flash memory, it plays the role of a hard disk drive in a general personal computer. A flash memory does not have a movable part and is resistant to impacts, and thus operates stably even in a poor ambient environment.

  The project file is a screen file in which data of one or more user screens (unit screens configured by screen data for one frame) displayed on the programmable display 2 are collected. The project file is usually composed of a series of a plurality of related screen data according to the target system 4 or a product manufactured by the target system 4. This project file is stored in a different file format (file format readable by the HMI control unit 21) from a project file created by a screen editor, which is screen creation software.

  The capture file is an image file of a ladder monitor screen captured by a ladder monitor unit 213 described later.

  The programmable display device 2 selects one screen data based on a unique screen number assigned to each screen number from the project file, and displays a user screen based on the screen data.

  The screen data includes a base screen to be displayed on the display 24, part data, processing definition information to be described later assigned to each part, and the like. This screen data includes a graphic data part and an address data part. The graphic data section stores graphic data and selected parts for the mark created by the user, and the address data section stores the addresses and addresses for the input marks and parts so as to correspond to the graphic data section. The comment corresponding to is stored. Specifically, each mark or part in the graphic data part is associated with a corresponding comment and address in the address data part.

  Comments include event names such as the operating status (start, stop, etc.) of the device 5, codes corresponding to the device 5 such as SW and lamp corresponding to the switch, LAMP, operation instructions, and control targets The physical quantity that becomes. Comments can also be handled as variables. The comment defined in this way is associated with a desired device address corresponding to the device 5 in advance.

  The screen data includes process definition information (tag) that defines various processes performed in relation to the user screen. This processing specification information is created for each event to be executed on the base screen. Basically, the file number (screen number) of the base screen on which the display processing is to be executed and the base screen are executed. An event name for specifying the operation content to be performed and reference information including one or a plurality of data referred to for each execution event are provided as a set.

  In the programmable display device 2 according to the present embodiment, as the above-described tag, a display tag indicating the correspondence between the region (display range) on the base screen and the device address of the device corresponding to the display in the region, and the screen A touch input tag indicating the correspondence between an area (input range) and an address corresponding to a touch input to the area is defined. Furthermore, in this embodiment, each tag can be associated with at least one of a plurality of user screens.

  The work memory 23 is composed of, for example, a DRAM, and is used for temporary storage of data exchanged with the PLC 3 in addition to being used for work during arithmetic processing such as display control. In particular, the DRAM has a state memory area for transferring the state of the device 5 (the contents of the device address) stored in the PLC 3 memory to and from the PLC 3 memory. The work memory 23 also includes a VRAM that develops an image to be displayed on the display. In this VRAM, the image of the screen data output from the data memory 22 is stored as dot data in the order displayed in the horizontal direction.

  The HMI control unit 21 is a functional block realized by causing an arithmetic processing means such as a CPU provided in the programmable display 2 to execute the HMI control program. The above-mentioned HMI control program can be recorded on a recording medium configured to be separable from the programmable display 2 and may be installed in the programmable display 2 from the recording medium. The HMI control program is individually prepared for each model in order to exhibit a function corresponding to the model of the programmable display device 2.

  The above recording media include tape systems such as magnetic tapes and cassette tapes, magnetic disk systems such as flexible disks and hard disks, optical disk systems such as CD-ROM, MO, MD, and DVD, IC cards (including memory cards), optical A card system such as a card is preferred. In addition, the program medium may be a medium that carries a fixed program including a semiconductor memory such as a mask ROM, EPROM, EEPROM, flash ROM, or the like.

  Further, if the control system 1 is configured to be connectable to a communication network including the Internet, it may be a medium that carries the program in a fluid manner so as to download the program from the communication network. However, when the program is downloaded from the communication network in this way, the download program may be stored in advance in the programmable display 2 or may be installed from another recording medium.

  The HMI control unit 21 performs central control operations of the HMI function such as display control of the user screen, control of input operation via the user screen, and control of communication with a connected device such as the PLC 3. The HMI control unit 21 includes a communication / display processing unit 211, a data logging unit 212, and a ladder monitor unit 213.

  When the communication / display processing unit 211 acquires the state of the device 5 and displays it on the user screen, the communication / display processing unit 211 appropriately transmits necessary information among the state information indicated by the bit device or the word device set in the memory in the PLC 3. While reading the data into the data memory, the display tag is repeatedly read, and the part of the expression format specified by the display tag is displayed in a specified area on the screen in a form corresponding to the read value. As a result, a display operation that changes according to a change in the state of the bit device or the word device is executed, and the state of the device 5 acquired from the PLC 3 is reflected in the display state of the parts on the user screen.

  In addition, when the ladder monitor unit 213 performs ladder monitoring in the monitor mode described later, the communication / display processing unit 211 requests the PLC 3 for a sequence program for monitoring the execution status, and is transmitted from the PLC 3 in response to the request. It is acquired by receiving the sequence program.

  In addition, the programmable display 2 may be provided with the function as a control apparatus (PLC), as described in patent documents 1 and 2. In such a programmable display 2, the sequence program is stored in the data memory 22, and when operating as a control device, the sequence program is read from the data memory 22 and developed in the work memory 23.

  When the programmable display 2 operates as a control device, the communication / display processing unit 211 is necessary information among the state information indicated by the bit device or the word device set in the data memory 22 instead of the memory of the PLC 3. The above display tag is repeatedly read while referring to the above, and the part of the expression format specified by the display tag is displayed in the specified area on the screen in a form corresponding to the read value. As a result, a display operation that changes according to a change in the state of the bit device or the word device is executed, and the state of the device 5 acquired from the device 5 is reflected in the display state of the parts on the user screen.

  The communication / display processing unit 211 acquires a sequence program for monitoring the execution status from the data memory 22 when performing ladder monitoring in the monitor mode.

  When the communication / display processing unit 211 gives a control instruction to the device 5 by a touch input on the user screen, the communication / display processing unit 211 repeatedly reads out the touch input tag described above and includes a predetermined user screen predetermined information included in the reference information in the touch input tag. The contents specified by the effective input coordinate range in which the input by touch is effective for specifying the touch position in the area, and the event name specifying the operation of the touch panel 25 (numerical value input operation, ON / OFF operation, etc.) The operation is set in the memory in the PLC 3 as a bit device or a word device. Further, when the programmable display device 2 operates as a control device, the HMI control unit 21 repeatedly reads out the touch input tag and specifies the effective input coordinate range included in the reference information in the touch input tag and the operation of the touch panel 25. The operation specified by the event name or the like is set as a bit device or a word device in the data memory instead of the PLC 3 memory. Thereby, in the PLC 3 or the programmable display 2 that changes in accordance with the change in the state of the bit device or the word device, the set control instruction is executed as the above operation, and the state of the device 5 changes.

  The data logging unit 212 temporarily stores the currently executed ladder program acquired from the PLC 3 by the communication / display processing unit 211 in the logging memory 14 (memory card 11 or the like), and then expands it in the work memory 23. . In addition, the data logging unit 212 sequentially writes the device data acquired from the PLC 3 by the programmable display 2 by the communication / display processing unit 211 at the preset timing in the above-described logging memory 14. This timing includes every predetermined time, predetermined time, when the PLC 3 is activated, when a predetermined bit in the device memory of the PLC 3 is turned on or off, and the like. Further, the data logging unit 212 sequentially reads out the designated device data in response to a request from the ladder monitor unit 213.

  When the timing is not specified, all acquired device data is written to the logging memory 14 in time series. The device data is written to the logging memory 14 when the timing is designated, for example, as follows. As shown in FIG. 4, the data logging unit 212 sequentially writes the acquired device data in the ring buffer RB provided in the programmable display 2. Then, at the designated timing, the pointer control unit of the ring buffer RB executes reading of desired device data. As a result, only desired device data is read from the ring buffer RB from the device data stored in the ring buffer RB and further written to the logging memory 14 by the data logging unit 212.

  In the logging memory 14, sequentially written device data is managed in the form of a database for each PLC 3 connected to the programmable display 2. Specifically, each item such as “data generation date and time” and “ladder program file name”, bit data and word data obtained by executing a ladder program such as “bit ON / OFF”, “quantity”, etc. Is provided as a field. One record is formed by these fields, and each record is written in the date order. In the logging memory 14, a sequential file structure is formed in which records are stored in the order of input. This enables sequential access to retrieve records in order of time.

  The ladder monitor unit 213 acquires a currently executed ladder program from the PLC 3 via the communication / display processing unit 211, and device data obtained by executing the ladder program from the PLC 3 device memory. get. The ladder monitor unit 213 acquires the ladder program and device data written from the logging memory 14.

  The ladder monitor unit 213 passes the ladder program developed in the work memory 23 to the communication / display processing unit 211 and displays the ladder program on a ladder monitor screen 101 for ladder monitor as shown in FIG. 2, for example, as a ladder diagram. About the display method of a ladder program, the display method similar to the ladder monitor function which a general ladder editor has may be used, and the display method described in patent document 1 may be used. Further, the ladder monitor unit 213 causes the communication / display processing unit 211 to display the acquired device data on the ladder monitor screen 101 as a state corresponding to the device data.

  For example, a portion that is conductive on the circuit (on the connection line) is displayed as a thick line or brightly, and a non-conductive portion is displayed as a thin line. Thereby, it is possible to confirm on the ladder monitor screen 101 which device 5 is conducting on the circuit. In the example shown in FIG. 2, since the b-contact of the second rung is displayed with a thick line, it can be seen that the b-contact is conductive. For example, even if the limit switch of the device 5 is not pressed in appearance, if the b contact whose device address is X000.1 is in the open (OPEN) state, the cable may be disconnected or the switch contact may be defective. .

  In addition, when the touch switches 101a to 101e provided on the ladder monitor screen 101 are touch-operated by the user, the ladder monitor unit 213 instructs each unit to perform an operation corresponding to each of the touch switches 101a to 101e. give. Here, operations performed by the touch switches 101a to 101e will be described.

  The touch switch 101 b is a switch for reproducing the execution status of the ladder program based on the device data stored in the logging memory 14. The ladder monitor unit 213 instructs the data logging unit 212 to read the device data from the logging memory 14 by touching the touch switch 101b, and sequentially supplies the read device data to the communication / display processing unit 211, so that the device The data change is displayed on the ladder monitor screen 101.

  The touch switch 101a is a switch for setting the generation time of device data for specifying the start time when reproducing the execution status of the ladder program. The ladder monitor unit 213 displays a dialog box (not shown) for time setting by a touch operation of the touch switch 101a. In addition, when the time is set in the dialog box by the user, the ladder monitor unit 213 gives the time to the data logging unit 212. Then, the data logging unit 212 searches for device data using the time as a key, and reads the device data in time series from the hit device data. The ladder monitor unit 213 reproduces the execution status of the ladder program as described above based on the read device data.

  The touch switch 101c is a switch for temporarily stopping the reproduction of the execution status of the ladder program. The ladder monitor unit 213 instructs the data logging unit 212 to pause reading of device data by a touch operation of the touch switch 101c. In addition, when the touch switch 101c is touched again, the ladder monitor unit 213 instructs the data logging unit 212 to resume reading device data.

  The touch switch 101d is a switch for printing out the currently displayed ladder monitor screen 101. The ladder monitor unit 213 captures the currently displayed ladder monitor screen 101 as an image file by a touch operation of the touch switch 101d, and outputs the captured image to a printer (not shown) connected to the programmable display 2. For this reason, although not shown, the programmable display device 2 includes a printer interface.

  The touch switch 101e is a switch for saving the currently displayed ladder monitor screen 101 as a file. The ladder monitor unit 213 captures the currently displayed ladder monitor screen 101 as an image file by a touch operation of the touch switch 101e, and saves it in the data memory 22, the logging memory 14, or the like.

  The ladder monitor unit 213 includes a communication switching unit 213a that switches a communication path in order to acquire a ladder program and device data from either the PLC 3 or the logging memory 14. As shown in FIG. 3, the communication switching unit 213a obtains device data from the ladder program currently being executed from the PLC 3, and in the monitor mode for performing ladder monitoring, the programmable display 2 (status memory area) from the PLC 3. The device data taken in is guided to the ladder monitor unit 213. On the other hand, the communication switching unit 213a acquires device data for a ladder program already executed from the logging memory 14 and reproduces the execution status of the ladder program from the logging memory 14 via the data logging unit 212 in the reproduction mode. The device data read in this way is guided to the ladder monitor unit 213.

  Here, the operation of the control system 1 configured as described above will be described.

  First, in the monitor mode, as shown in FIG. 3, when the currently executed ladder program is acquired from the PLC 3 via the communication switching unit 213a, the ladder monitor unit 213 and the communication / display processing unit 211 display the ladder program. 24 is displayed as a ladder monitor screen 101. Subsequently, when the device data obtained with the execution of the ladder program is acquired from the PLC 3 via the communication switching unit 213a, the ladder monitor unit 213 and the communication / display processing unit 211 change the device data. It is displayed on the ladder monitor screen 101. In this way, changes in device data are displayed on the ladder monitor screen 101 as the execution status of the ladder program.

  In addition, the data logging unit 212 writes the currently executed ladder program acquired from the PLC 3 in the logging memory 14. Further, the data logging unit 212 writes the device data obtained along with the execution of the ladder program to the logging memory 14 in time series at a designated timing.

  On the other hand, in the playback mode, when the ladder program read by the data logging unit 212 is acquired via the communication switching unit 213a, the ladder monitor screen is displayed on the display 24 by the ladder monitor unit 213 and the communication / display processing unit 211. 101 is displayed. Subsequently, when the device data sequentially read by the data logging unit 212 is acquired via the communication switching unit 213a, the ladder monitor unit 213 and the communication / display processing unit 211 change the device data to the ladder monitor. It is displayed on the screen 101. In this way, the change in device data is displayed on the ladder monitor screen 101 as a reproduction of the execution status of the ladder program.

  At this time, if any of the touch switches 101a to 101e on the ladder monitor screen 101 is touched by the user, the respective processes are performed.

  As described above, the programmable display device 2 according to the present embodiment stores the device data acquired from the PLC 3 in the logging memory 14, and the ladder monitor unit 213 executes the ladder program that has already been executed based on the device data. The situation is reproduced on the ladder monitor screen 101. Further, in order to perform the monitor mode and the playback mode, the communication switching unit 213a switches the communication path through which the ladder monitor unit 213 acquires device data from the PLC 3 or the logging memory 14. As a result, the programmable display 2 can perform ladder monitoring in real time, and reproduces the execution status of the ladder monitor that has already been executed based on the stored device data and displays it in the same manner as during ladder monitoring. be able to.

  Therefore, the execution status of the ladder program executed in the past can be displayed even on the programmable display 2 having no PLC control function. Of course, a programmable display having a PLC control function may include the configuration of the present embodiment.

  Moreover, since the execution status of the ladder program is displayed on the programmable display 2 and the device data is stored in the logging memory 14 provided on the programmable display 2 side, the system configuration for displaying the execution status of the ladder program is simplified. Can be

  In this embodiment, the function as the logging memory 14 is given to the memory card 11 and the USB memory 12 which are detachably attached to the programmable display 2. However, the same function is provided in the internal memory (for example, data) of the programmable display 2. Memory). Although contrary to the simplification of the system configuration, the FTP server 13 connected to the network 7 can also be used as the logging memory 14 in an environment where the programmable display 2 is connected to the network 7. In this configuration, a specific file of the FTP server 13 has a role as the logging memory 14 and a ladder program and device data are written to the file. As a result, the capacity of the logging memory 14 can be easily increased, which is particularly suitable for a network system.

  Even when the programmable display 2 has a PLC control function, the device data updated by executing the ladder program is stored in the logging memory 14 in the same manner as the device data acquired from the external PLC 3. The ladder monitor unit 213 may reproduce and display the execution status of the ladder program based on the device data. Thereby, the execution situation of the ladder program executed in the programmable display in the past can be reproduced similarly to the programmable display having the control function described in Patent Document 2. Therefore, in such a programmable display device 2, not only the ladder program executed by the external PLC 3 but also the execution status of the ladder program executed by the internal control function can be reproduced.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and the embodiments can be obtained by appropriately combining technical means disclosed in different embodiments. The form is also included in the technical scope of the present invention.

  The programmable display of the present invention displays the execution status of the ladder program in real time, and also has the function of reproducing and displaying the execution status of the ladder program already executed based on the stored device data, thereby providing a programmable display. The ladder program can be verified at the site where the equipment is installed, and it is possible to easily check for problems in the ladder program.

It is a block diagram which shows the structure of the control system which concerns on embodiment of this invention. It is a figure which shows the ladder monitor screen for carrying out the monitor display or reproduction | regeneration display of the execution condition of a ladder program with the programmable display in the said control system. It is a block diagram which shows the processing system which acquires the device data from PLC or a logging memory, and displays the execution condition of a ladder program in the said control system. It is a figure which shows the specific example which writes device data from the said PLC into the said logging memory.

Explanation of symbols

2 Programmable display 11 Memory card (data storage device, program storage device)
12 USB memory (data storage device, program storage device)
14 Logging memory (storage device)
22 Data memory (storage device)
211 Communication / display processing unit (data acquisition means, program acquisition means)
212 Data logging unit (data writing / reading means, program writing / reading means)
213 Ladder monitor (execution status display means)
213a Communication switching unit (device data selection means)

Claims (4)

A data acquisition means for communicatively connecting to a control device for controlling a device according to a sequence program and acquiring device data updated by the execution of the sequence program;
A data storage device for storing the device data;
A programmable display comprising data writing / reading means for writing the device data acquired by the data acquisition means to the data storage device and reading from the data storage device,
Program acquisition means for acquiring the sequence program from the control device;
A program storage device for storing the sequence program;
Program writing / reading means for writing the sequence program acquired by the program acquisition means to the program storage device and reading the sequence program from the program storage device;
Execution status display means for displaying the execution status of the sequence program read by the program writing / reading means based on the device data read by the data writing / reading means. Features programmable display.   As the device data based on which the execution status display means displays the execution status of the sequence program, it is read by the data writing / reading means from the device data acquired by the data acquisition means or the data storage device. 2. The programmable display device according to claim 1, further comprising device data selection means for selecting any one of the device data.   A display program for operating the programmable display device according to claim 1 or 2 for causing a computer to function as each means.   A computer-readable recording medium on which the display program according to claim 3 is recorded.

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