JP6349805B2 - Communication unit, controller, control system, control method, and program - Google Patents

Description

  The present invention relates to data transmission in a control system used to control the operation of a machine or equipment.

  Machines and equipment used in many production sites are typically controlled by a control system including a programmable controller (hereinafter also referred to as “PLC”). In such a control system, the PLC includes a CPU unit and an IO (Input Output) unit in charge of signal input from an external switch or sensor and signal output to an external relay or actuator. The PLC is connected to a plurality of remote IO terminals via a network. Each remote IO terminal includes a communication coupler and a plurality of IO units.

  As a control system as described above, Patent Document 1 discloses a system (PLC remote IO system) including a PLC main body and a plurality of remote slaves connected to the PLC main body through a serial IF (Interface). Yes. The PLC main body includes a master unit, a plurality of IO units, and a CPU unit. The master unit, the plurality of IO units, and the CPU unit are connected to each other so as to communicate with each other through a parallel IF. Each remote slave is connected to a switch, sensor, relay, valve and the like.

In the master unit of the PLC main body, a join flag indicating whether or not a remote slave is connected is set. The subscription flag is stored in a channel address (slave subscription state setting area) accessible by execution of the user program. With this configuration, the system of Patent Document 1 executes the user program after the input initial value is reflected after the power is turned on, without registering the remote slave joining status and creating an actual I / O table. It is possible.

  In the control system, the CPU unit operates as a master device and inputs / outputs signals with at least one communication coupler. For the CPU unit that operates as a master device, the communication coupler included in the remote IO terminal becomes a slave device, but the communication coupler functions as a master device for the IO unit connected to the communication coupler. In such a control system, an information processing device such as a PC (Personal Computer) is connected to a master device such as a CPU unit or communication coupler via a communication interface such as USB (Universal Serial Bus) in order to set up a network. Various settings can be made from the support software running on the processing device. For example, a PC is connected to the CPU unit, and IO refresh communication between the CPU unit and the communication coupler can be dynamically stopped or started on support software operating on the PC.

Japanese Patent Laid-Open No. 9-128020

  There is a case where a PC is directly connected to a communication coupler connected to the CPU unit by, for example, a field network or the like via a USB or the like, and an IO check for confirming data input / output with the IO unit connected to the communication coupler is desired. If the I / O refresh between the communication coupler and the CPU unit that is the master device is functioning, stop the I / O refresh from the viewpoint of safety, etc., check the IO of the communication coupler, After completion, it is desirable to enable I / O refresh between the communication coupler and the CPU unit as the master device again. For this reason, normally, in order to stop the I / O refresh between the communication coupler and the CPU unit serving as the master device, it is first necessary to connect a PC or the like to the CPU unit serving as the master device (or the controller that manages the CPU unit). . Therefore, it is necessary to change the connection destination of an information processing device such as a PC each time to perform an IO check of a communication coupler, and there is a risk that the startup, maintenance, maintenance, etc. of a remote IO terminal as a slave device will be complicated. There is. In particular, the master device and the slave device may be physically separated from each other, and it is also necessary for the operator to reciprocate between the master device and the communication coupler for IO check of the communication coupler. It becomes. It is also possible to physically cut off the connection between the master device and the slave device, but in this case, the IO refresh may stop until another slave device connected to the master device. There are also problems such as the detection of errors and the history of errors.

  The present invention has been made in view of the above-described problems, and its purpose is to provide a technique for facilitating the startup, maintenance, and maintenance of a remote IO terminal as a slave device with respect to a master device in a control system. It is to provide.

  According to one embodiment, a communication unit is provided that functions as a master device and is communicably connected to a plurality of slave devices via a system bus. The communication unit is communicably connected to the controller arithmetic unit via a network. The controller communicates with at least one communication unit via the network, manages whether to enable data input / output processing with the communication unit, and inputs / outputs data to / from the communication unit from the communication unit. A signal indicating whether to enable or not is received via the network. The communication unit includes a communication unit that communicates with the controller via a network, a reception unit that receives an input operation for instructing whether the controller enables data input / output processing with the communication unit, and an input operation performed by the reception unit. And a control unit that transmits a signal indicating an instruction that has been received by the communication unit to the controller via the network.

  Preferably, the communication unit includes a communication interface for accepting a connection of an external information processing apparatus, and the external information processing apparatus connected by the communication interface allows the accepting unit to accept an input of an instruction, The controller accepts an input operation as to whether to enable data input / output processing with the communication unit, transmits a signal corresponding to the accepted input operation to the communication unit, and the communication unit receives the transmitted signal. The control unit transmits a signal corresponding to the input operation received by the connected external information processing apparatus to the controller as a signal indicating an instruction.

  Preferably, the accepting unit is a switching member that accepts an instruction as to whether or not the controller enables data input / output processing with the communication unit by switching on or off, and the control unit accepts the switching unit. A signal corresponding to the input operation is transmitted to the controller.

  Preferably, the controller executes a program to be managed periodically or in an event manner to perform a communication unit to be managed, event data input / output processing, and periodic data input / output processing. The communication unit performs data input / output processing with the controller according to the cycle, and transmits a signal corresponding to the instruction received by the receiving unit to the controller through event-like data input / output processing.

  Preferably, the communication unit is a communication coupler connected to the arithmetic unit of the controller via a field network.

  According to one embodiment, the communication unit communicates with at least one communication unit via a network, manages whether to enable data input / output processing with the communication unit, and transmits data from the communication unit to the communication unit. There is provided a controller that receives a signal as to whether or not to enable the input / output of the network via a network. The controller stores unit organization information for managing the communication unit to be managed in the storage unit. The communication unit functions as a master device and is communicably connected to a plurality of slave devices via a system bus. The communication unit communicates with the controller via a network, and the controller enables data input / output processing with the communication unit. A reception unit that receives an input operation of an instruction to determine whether or not to perform an operation, and a control unit that transmits a signal indicating the instruction received by the reception unit to the controller via a network. The controller receives a signal indicating whether the controller enables data input / output processing with the communication unit from the communication unit, and updates the unit organization information according to the signal. And an input / output control unit for controlling whether to enable data input / output processing with the communication unit.

  According to one embodiment, a communication unit that functions as a master device and is communicably connected to a plurality of slave devices via a system bus, and communicates with at least one communication unit via a network, and data with the communication unit There is provided a control system including a controller that receives a signal indicating whether or not to enable the input / output processing via a network. The controller stores unit organization information for managing the communication unit to be managed in the storage unit. The communication unit includes a communication unit that communicates with the arithmetic unit of the controller via a network, a reception unit that receives an input operation of an instruction as to whether the controller enables data input / output processing with the communication unit, and a reception unit And a control unit that transmits a signal indicating an instruction for accepting the input operation to the controller via the network by the communication unit. The controller receives a signal indicating whether the controller enables data input / output processing with the communication unit from the communication unit, and updates the unit organization information according to the signal. And an input / output control unit for controlling whether to enable data input / output processing with the communication unit.

  According to one embodiment, a communication unit that functions as a master device and is communicably connected to a plurality of slave devices via a system bus, and communicates with at least one communication unit via a network, and data with the communication unit There is provided a method for controlling data input / output processing in a control system comprising a controller that receives a signal indicating whether to enable the input / output processing via a network. The controller stores unit organization information for managing the communication unit to be managed in the storage unit. The communication unit includes a communication unit that communicates with the arithmetic unit of the controller via a network. The control method includes a step in which the communication unit receives an input operation indicating whether or not the controller enables data input / output processing with the communication unit, and a signal indicating an instruction in which the communication unit has received the input operation. , Transmitting to the controller by the communication unit via the network, and the controller receiving a signal from the communication unit indicating whether or not the controller enables data input / output processing with the communication unit via the network. And a step in which the controller updates whether or not to enable data input / output processing with the communication unit by updating the unit organization information according to the signal.

According to one embodiment, a program for controlling the operation of a communication unit that functions as a master device and is communicably connected to a plurality of slave devices via a system bus,
The communication unit includes a processor and a memory, and includes a communication unit that communicates with the arithmetic unit of the controller via a network. The controller communicates with at least one communication unit via the network, manages whether to enable data input / output processing with the communication unit, and inputs / outputs data to / from the communication unit from the communication unit. A signal indicating whether to enable or not is received via the network. The program receives a signal indicating an instruction for accepting an input operation in the accepting step and a step for accepting an input operation as to whether or not the controller enables data input / output processing with the communication unit from the network. And transmitting to the controller via the communication unit.

  According to the present invention, a communication unit such as a communication coupler can instruct a controller that manages a communication unit via a network whether to enable data input / output processing. Slave devices can be easily started up, maintained, and maintained.

It is a schematic diagram which shows schematic structure of the PLC system which concerns on embodiment of this invention. It is a schematic diagram which shows the connection structure of the remote IO terminal 5 which concerns on embodiment of this invention. It is a schematic diagram which shows the hardware constitutions of the communication coupler 52 which comprises the remote IO terminal 5 which concerns on embodiment of this invention. It is a schematic diagram which shows the hardware constitutions of the PLC support apparatus 8 used by connecting with the CPU unit 13 and the communication coupler 52 which concern on embodiment of this invention. It is a figure which shows the data structure of IO unit organization information 320 stored in CPU unit 13. 7 is a flowchart showing processing for connecting the PLC support device 8 to the communication coupler 52 and stopping the IO refresh between the communication coupler 52 and the CPU unit 13 from the communication coupler 52 to the CPU unit 13. 7 is a flowchart showing processing for connecting the PLC support device 8 to the communication coupler 52 and causing the CPU coupler 13 to start IO refresh between the communication coupler 52 and the CPU unit 13 from the communication coupler 52. 6 is a diagram for explaining an example of a user interface for setting the IO refresh setting of the communication coupler 52 by the PLC support device 8. FIG.

  Embodiments of the present invention will be described in detail with reference to the drawings. In addition, about the same or equivalent part in a figure, the same code | symbol is attached | subjected and the description is not repeated.

<A. Overall configuration of PLC system>
A PLC (Programmable Logic Controller) according to the present embodiment controls, for example, a machine in a production facility or the like, and controls operations of switches, sensors, relays, and the like. The PLC has, for example, a motion control function for controlling the motion of the motor. First, the system configuration of the PLC 1 according to the present embodiment will be described with reference to FIG.

  FIG. 1 is a schematic diagram showing a schematic configuration of a PLC system according to an embodiment of the present invention. Referring to FIG. 1, PLC system SYS includes PLC 1, servo motor driver 3 and remote IO terminal 5 connected to PLC 1 via field network 2, detection switch 6 and relay 7 which are field devices. . The PLC support device 8 is connected to the PLC 1 and the remote IO terminal 5 via a connection cable 10 or the like.

  The PLC 1 that is the main device includes a CPU unit 13 that executes main arithmetic processing, one or more IO units 14, and a special unit 15. These units are configured to exchange data with each other via the PLC system bus 11. These units are supplied with power of an appropriate voltage by the power supply unit 12.

  The IO unit 14 is a unit related to general input / output processing, and controls input / output of binarized data such as on / off. In other words, the IO unit 14 collects information indicating whether a sensor such as the detection switch 6 is detecting a certain object (on) or not detecting any object (off). . In addition, the IO unit 14 outputs either an activation command (ON) or an inactivation command (OFF) to an output destination such as the relay 7 or the actuator.

  The special unit 15 has functions not supported by the IO unit 14 such as input / output of analog data, temperature control, and communication using a specific communication method.

  The field network 2 transmits various data exchanged with the CPU unit 13. As the field network 2, typically, various types of industrial Ethernet (registered trademark) can be used.

  1 illustrates a PLC system SYS having both the PLC system bus 11 and the field network 2, but a system configuration in which only one of them is mounted may be employed. For example, all units may be connected by the field network 2. Alternatively, the servo motor driver 3 may be directly connected to the PLC system bus 11 without using the field network 2. Further, a communication unit of the field network 2 may be connected to the PLC system bus 11 so that the CPU unit 13 communicates with a device connected to the field network 2 via the communication unit.

  The servo motor driver 3 is connected to the CPU unit 13 via the field network 2 and drives the servo motor 4 according to a command value from the CPU unit 13. More specifically, the servo motor driver 3 receives command values such as a position command value, a speed command value, and a torque command value from the PLC 1 at a constant cycle. The servo motor driver 3 receives a position and speed (typically from the difference between the current position and the previous position) from a detector such as a position sensor (rotary encoder) or torque sensor connected to the shaft of the servo motor 4. (Calculated), an actual measurement value related to the operation of the servo motor 4 such as torque is acquired. Then, the servo motor driver 3 sets a command value from the CPU unit 13 as a target value, and performs feedback control using the actually measured value as a feedback value. That is, the servo motor driver 3 adjusts the current for driving the servo motor 4 so that the actual measurement value approaches the target value. The servo motor driver 3 may be referred to as a servo motor amplifier.

  1 shows a system example in which the servo motor 4 and the servo motor driver 3 are combined, but other configurations, for example, a system in which a pulse motor and a pulse motor driver are combined may be employed.

  A remote IO terminal 5 is further connected to the field network 2 of the PLC system SYS shown in FIG. The remote IO terminal 5 basically performs processing related to general input / output processing in the same manner as the IO unit 14. More specifically, the remote IO terminal 5 includes a communication coupler 52 for performing processing related to data transmission in the field network 2 and one or more IO units 53. As will be described below, these units are configured to exchange data with each other via a remote IO terminal bus 51 which is a system bus (internal bus).

  The communication coupler 52 mainly controls the operation of the IO unit 53 (IO data update timing and the like) and also controls data transmission with the PLC 1. The communication coupler 52 is connected to the CPU unit 13 of the PLC 1 via the field network 2. Details of the communication coupler 52 will be described later.

  The IO unit 53 is in charge of signal input from an external switch or sensor and signal output to an external relay or actuator. The IO unit 53 has a general input / output processing function in addition to the function of transmitting data via the communication coupler 52 and the remote IO terminal bus 51. Typically, the IO unit 53 inputs / outputs binarized data such as on / off. For example, the IO unit 53 collects information on whether a certain object is detected (on) or no object is detected (off) from the detection sensor. Further, the IO unit 53 gives either an instruction (ON) for activation (activation) or an instruction (OFF) for deactivation (deactivation) to an output destination such as a relay or an actuator. give.

  In addition to the communication coupler 52 and one or more IO units 53, the remote IO terminal 5 includes other types of units (special units, motion units, communication units) as communication coupler slave devices. May be. However, hereinafter, for convenience of explanation, the remote IO terminal 5 will be described as including the communication coupler 52 and one or more IO units 53 and not including the other types of units.

<B. Outline of processing>
The communication coupler 52, which is a communication unit, functions as a master device in the remote IO terminal 5 and is communicably connected by an IO unit 53 that operates based on predetermined setting information and a remote IO terminal bus 51. The communication coupler 52 stores setting information for each IO unit 53. The communication coupler 52 further stores a system program, and transmits each setting information to the corresponding IO unit 53 by executing the system program. Each setting information describes a setting value of each IO unit 53. The communication coupler 52 stores at least unit configuration information (not shown) representing the configuration of a system composed of a plurality of IO units 53.

  The communication coupler 52 as a communication unit is connected to the CPU unit 13 of the PLC 1 by the field network 2. The PLC 1 manages at least one remote IO terminal 5 via the field network 2 and controls data input / output processing with the remote IO terminal 5.

The communication coupler 52 holds as a flag whether to enable data input / output processing with the PLC 1. The communication coupler 52 may be directly connected to the PLC support device 8, whether the support software running on the PLC support device 8, the PLC support device 8, to enable the input and output processing of data with PLC1 The input operation is accepted and the flag is updated. The communication coupler 52 transmits a signal to the CPU unit 13 of the PLC 1 in response to an input operation as to whether or not to enable data input / output processing with the PLC 1. The CPU unit 13 receives a signal indicating whether or not to enable data input / output processing from the communication coupler 52, and performs data input / output processing (for example, IO refresh) with the remote IO terminal 5 serving as a slave device. Control.

  Below, the specific structure of PLC system SYS for implement | achieving the above processes is demonstrated. Furthermore, in the following, processes other than the above processes will be described as appropriate.

<C. Hardware configuration of remote IO terminal 5>
Next, a hardware configuration of the remote IO terminal 5 that is a control device that constitutes a part of the PLC system SYS according to the present embodiment will be described.

  FIG. 2 is a schematic diagram showing a connection configuration of the remote IO terminal 5 according to the embodiment of the present invention.

<C1. Connection configuration>
Referring to FIG. 2, in remote IO terminal 5, communication coupler 52 and one or more IO units 53-1, 53-2, and 53-3 (hereinafter may be collectively referred to as “IO unit 53”). Data can be transmitted to each other via a remote IO terminal bus 51 (downlink 511 and uplink 512) which is a communication line. That is, the remote IO terminal 5 includes a plurality of units (communication coupler 52 and IO unit 53) connected via a communication line.

  As an example, in the downlink 511 and the uplink 512, serial communication is adopted, and target data is transmitted in a form arranged in a line in time series. More specifically, in the downlink 511, data is transmitted in one direction via the downlink 511 from the communication coupler 52 functioning as a master control unit to the IO unit 53 functioning as a slave control unit. On the other hand, in the uplink 512, data is transmitted in one direction via the uplink 512 from one of the IO units 53 to the communication coupler 52.

  In the present embodiment, data is transmitted as a frame including header information. Each frame is composed of one or a plurality of blocks. The header information includes information indicating the priority of data in the frame. The header information includes information related to the length of the frame. Details of the frame structure and the like will be described later.

  When each of the IO units 53 receives a frame transmitted on the downlink 511 or the uplink 512, the IO unit 53 decodes data from the frame and executes a necessary process. Each IO unit 53 regenerates the frame and then retransmits (forwards) the frame to the next IO unit 53.

  In order to realize such sequential transfer of frames including data, each IO unit 53 is also referred to as a reception unit (hereinafter also referred to as “RX”) 210 a and a transmission unit (hereinafter referred to as “TX”) with respect to the downlink 511. ) 210b and for uplink 512, it includes a receiver 220a and a transmitter 220b. The receiving units 210a and 220a receive data transmitted as frames from other units via the remote IO terminal bus 51 which is a communication line. The transmission units 210b and 220b transmit data as frames to other units via the remote IO terminal bus 51 which is a communication line.

  Each IO unit 53 includes a processor 200 as a control unit, and the processor 200 controls processing of these data.

  The communication coupler 52 includes a processor 100, a fieldbus control unit 110, a reception unit 112, a transmission unit 114, an internal bus control unit 130, and a communication I / F (Interface) 190. That is, the communication coupler 52 is not only connected to the remote IO terminal bus 51 (downlink 511 and uplink 512) but also connected to the field network 2 that is a higher-level communication network via the reception unit 112 and the transmission unit 114. Is done. The field bus control unit 110 manages data transmission via the field network 2, and the internal bus control unit 130 manages data transmission via the remote IO terminal bus 51. Communication I / F 190 functions as an interface for accepting connection of external PLC support device 8 via a cable or the like.

<C2. Configuration of Communication Coupler 52>
FIG. 3 is a schematic diagram showing a hardware configuration of the communication coupler 52 constituting the remote IO terminal 5 according to the embodiment of the present invention.

  Referring to FIG. 3, the communication coupler 52 of the remote IO terminal 5 includes a processor 100, a nonvolatile memory 101, a field bus control unit 110, a reception unit 112, a transmission unit 114, and an internal bus control unit 130. including.

  The receiving unit 112 receives an upper communication frame transmitted from the PLC 1 via the field network 2, decodes it into data, and outputs the data to the fieldbus control unit 110. The transmission unit 114 regenerates the upper communication frame from the data output from the fieldbus control unit 110 and retransmits (forwards) it through the field network 2.

The field bus control unit 110 cooperates with the reception unit 112 and the transmission unit 114 to communicate with other devices (PLC 1 and other remote IO terminals 5) every predetermined control cycle via the field network 2. Send and receive data with. More specifically, the fieldbus control unit 110 includes a fieldbus communication controller 120, a memory controller 122, a FIFO (First In First Out) memory 124, a reception buffer 126, and a transmission buffer 128.

The host communication controller 120 interprets a command or the like transmitted from the PLC 1 via the field network 2 and executes processing necessary for realizing communication via the field network 2. Further, the fieldbus communication controller 120 performs data copy processing from the upper communication frame and data write processing to the upper communication frame that are sequentially stored in the FIFO memory 124.

  The memory controller 122 is a control circuit that realizes a function such as DMA (Dynamic Memory Access), and controls writing / reading of data to / from the FIFO memory 124, the reception buffer 126, the transmission buffer 128, and the like.

  The FIFO memory 124 temporarily stores the upper communication frames received via the field network 2 and sequentially outputs the upper communication frames according to the stored order. The reception buffer 126 extracts data indicating a state value to be output from the output unit of the IO unit 53 connected to the own device from the data included in the upper communication frame sequentially stored in the FIFO memory 124 and temporarily stores the data. To store. The transmission buffer 128 is process data indicating a state value detected at the input unit of the IO unit 53, and temporarily stores data to be written in a predetermined area of the upper communication frame sequentially stored in the FIFO memory 124. .

  The processor 100 gives an instruction to the field bus control unit 110 and the internal bus control unit 130 and controls data transfer between the field bus control unit 110 and the internal bus control unit 130.

  The nonvolatile memory 101 includes a refresh stop flag 103 indicating that data input / output processing with the PLC 1 is stopped, a refresh start flag 105 indicating that data input / output processing with the PLC 1 is started, and each IO unit 53. Stores setting information. Specifically, the nonvolatile memory 101 stores system configuration information including unit configuration information.

  The internal bus control unit 130 transmits and receives frames (data) to and from the IO unit 53 via the remote IO terminal bus 51 (downlink 511 and uplink 512).

  More specifically, the internal bus control unit 130 includes an internal bus communication controller 132, a transmission circuit 142, a reception circuit 144, and a storage device 160.

  The internal bus communication controller 132 mainly manages (as a master) data transmission via the remote IO terminal bus 51.

  The transmission circuit 142 generates and transmits a frame that flows on the downlink of the remote IO terminal bus 51 in accordance with an instruction from the internal bus communication controller 132. The reception circuit 144 receives a frame flowing on the uplink of the remote IO terminal bus 51 and outputs it to the internal bus communication controller 132.

  The storage device 160 corresponds to a buffer memory that stores frames (data) transmitted through the remote IO terminal bus 51. More specifically, the storage device 160 includes a shared memory 162, a reception buffer 164, and a transmission buffer 166. Shared memory 162 temporarily stores data exchanged between fieldbus control unit 110 and internal bus control unit 130. The reception buffer 164 temporarily stores data received from the IO unit 53 via the remote IO terminal bus 51. The transmission buffer 166 temporarily stores data included in the upper communication frame received by the fieldbus control unit 110.

  Communication I / F 190 functions as an interface for accepting connection of external PLC support device 8 via a cable or the like.

<D. PLC support device>
FIG. 4 is a schematic diagram showing a hardware configuration of the PLC support device 8 used by being connected to the CPU unit 13 and the communication coupler 52 according to the embodiment of the present invention. Referring to FIG. 4, PLC support device 8 is typically configured by a general-purpose computer. From the viewpoint of maintainability, a notebook personal computer with excellent portability is preferable.

  Referring to FIG. 4, PLC support device 8 includes a CPU 81 that executes various programs including an OS, a ROM (Read Only Memory) 82 that stores BIOS and various data, and data necessary for execution of the program by CPU 81. A memory RAM 83 that provides a work area for storing the program, and a hard disk (HDD) 84 that stores programs executed by the CPU 81 in a nonvolatile manner.

  The PLC support device 8 further includes a keyboard 85 and a mouse 86 that receive operations from the user, and a display 87 for presenting information to the user. Furthermore, the PLC support device 8 includes a CD-ROM (Compact Disk-Read Only Memory) drive device 88 and a communication interface (IF) 89 for communicating with the PLC 1 (CPU unit 13) and the like.

  As will be described later, various programs executed by the PLC support device 8 are stored and distributed in a recording medium such as an optical disc such as a CD-ROM 9. The program stored in the CD-ROM 9 is read by the CD-ROM driving device 88 and stored in the hard disk (HDD) 84 or the like. Alternatively, the program may be downloaded from a host computer or the like via a network.

In the present embodiment, input / output processing such as IO refresh between the communication coupler 52 and the CPU unit 13 of the PLC 1 is controlled by a support program operating in the PLC support device 8. Specifically, the user of the PLC system SYS connects the PLC support device 8 to the communication coupler 52 and stops or starts IO refresh between the communication coupler 52 and the CPU unit 13 (data input / output processing is performed). The user inputs an instruction whether to enable or not. The PLC support device 8 transmits the instruction content input by the user to the communication coupler 52. The communication coupler 52 receives the instruction content input by the user and updates the refresh stop flag 103 or the refresh start flag 105. The communication coupler 52 communicates with the CPU unit 13 through the field network 2 and transmits a signal indicating the instruction content input by the user to the CPU unit 13. The communication coupler 52 includes a communication interface 190 used for communication with the PLC support device 8.

  In the above, the example in which the IO refresh between the communication coupler 52 and the PLC 1 is controlled by connecting the PLC support device 8 to the communication coupler 52 has been described. However, the present invention is not limited to this. For example, a physical member such as a switch for accepting an on / off input operation is arranged in the communication coupler 52, and the communication coupler 52 makes a user operation to the CPU unit 13 in response to the user's operation on the switch or the like. The instruction content (whether or not to enable input / output processing between the communication coupler 52 and the PLC 1) may be transmitted.

<E. Data>
Data used in the PLC system SYS will be described with reference to FIG. The CPU unit 13 of the PLC 1 functions as a master device for the remote IO terminal 5 and manages data input / output processing (IO refresh) with one or more remote IO terminals 5. The CPU unit 13 stores the managed remote IO terminal 5 as IO unit organization information 320.

FIG. 5 is a diagram illustrating a data structure of the IO unit organization information 320 stored in the storage unit 310 of the CPU unit 13. Referring to FIG. 5, IO unit organization information 320 includes a product code 322 and a product serial number 324 as information indicating a communication unit to be managed. The IO unit organization information 320 includes an IO refresh invalidation setting 326 that indicates whether data input / output processing with each slave device is valid. The product serial number 324 is a number unique to a product (communication coupler 52, IO unit 53, etc.).

  The support software that operates on the PLC support device 8 includes an editor program, a compiler program, a debugger program, a simulation sequence instruction calculation program, a simulation motion calculation program, and a communication program. Each program included in the support software is typically distributed in a state of being stored in a recording medium such as a CD-ROM and installed in the PLC support device 8. The user generates a user program using the support program.

  The IO refresh invalidation setting indicates whether IO refresh with the slave device is invalidated by 0 or 1.

<F. Control structure>
Next, operations in the PLC system SYS will be described with reference to FIGS. 6 and 7.

<F1. Stop IO refresh of communication coupler 52>
FIG. 6 is a flowchart showing processing for connecting the PLC support device 8 to the communication coupler 52 and causing the CPU coupler 13 to stop IO refresh between the communication coupler 52 and the CPU unit 13 from the communication coupler 52.

  In step S <b> 101, the PLC support device 8 receives an input operation for stopping IO refresh between the communication coupler and the PLC 1 from the user through the support software, and transmits a signal indicating the user's input operation to the communication coupler 52.

  In step S201, the communication coupler 52 receives the signal transmitted from the PLC support device 8 in step S101, and turns on the refresh stop flag 103. At this time, the communication coupler 52 may turn off the refresh start flag 105.

  In step S203, the communication coupler 52 requests the CPU unit 13 serving as a communication master device to stop IO refresh. For example, it is assumed that the CPU unit 13 executes a program periodically or in an event manner to perform periodic data input / output with the communication coupler 52 and event data input / output with the communication coupler 52. Periodic data input / output is used for data input / output that is preferably used when real-time processing is required, such as motor output control. The event-like data input / output is used for communication with a host controller, for example. The communication coupler 52 transmits a signal requesting to stop the IO refresh to the CPU unit 13 by a communication protocol (for example, UDP (User Datagram Protocol)) for inputting and outputting event data.

  In step S301, when the CPU unit 13 receives the IO refresh stop request from the communication coupler 52 via the field network 2, the IO unit organization information 320 is set to stop the IO refresh for the communication coupler 52 that has transmitted the IO refresh stop request. The IO refresh invalidation setting 326 is set to “invalid”.

  In step S <b> 303, the CPU unit 13 transmits a signal indicating that the IO refresh with the communication coupler 52 that has transmitted the IO refresh stop request is stopped to the communication coupler 52.

  In step S <b> 205, the communication coupler 52 receives the result of the IO refresh stop request from the CPU unit 13 and transmits the result to the PLC support device 8.

  In step S105, the PLC support device 8 receives the result of the IO refresh stop request from the communication coupler 52 and displays the result on the display 87.

<F2. Start of IO refresh of communication coupler 52>
FIG. 7 is a flowchart showing processing for connecting the PLC support device 8 to the communication coupler 52 and causing the CPU coupler 13 to start IO refresh between the communication coupler 52 and the CPU unit 13 from the communication coupler 52.

  In step S131, the PLC support device 8 receives an input operation for starting IO refresh between the communication coupler and the PLC 1 from the user through the support software, and transmits a signal indicating the input operation of the user to the communication coupler 52.

  In step S231, the communication coupler 52 receives the signal transmitted from the PLC support device 8 in step S131 and turns on the refresh start flag 105. At this time, the communication coupler 52 may turn off the refresh stop flag 103.

  In step S233, the communication coupler 52 requests the CPU unit 13 serving as a communication master device to start IO refresh. For example, the communication coupler 52 transmits a signal requesting the start of IO refresh to the CPU unit 13 by a communication protocol (for example, UDP) for inputting and outputting event data.

  In step S331, when the CPU unit 13 receives the IO refresh start request from the communication coupler 52 via the field network 2, the IO unit organization information 320 is set to start IO refresh for the communication coupler 52 that has transmitted the IO refresh start request. The IO refresh invalidation setting 326 is set to “valid”.

  In step S333, the CPU unit 13 transmits to the communication coupler 52 a signal indicating that IO refresh with the communication coupler 52 that has transmitted the IO refresh start request is started.

  In step S <b> 235, the communication coupler 52 receives the result of the IO refresh start request from the CPU unit 13 and transmits the result to the PLC support device 8.

  In step S <b> 135, the PLC support device 8 receives the result of the IO refresh start request from the communication coupler 52 and displays it on the display 87.

<G. Example of UI in PLC Support Device 8>
FIG. 8 is a diagram showing a screen on the display 87 of the PLC support device 8. Specifically, FIG. 8 is a diagram for explaining an example of a user interface for setting the IO refresh setting of the communication coupler 52 by the PLC support device 8.

  Referring to FIG. 8, PLC support device 8 shows a list of slave units (communication coupler 52 and the like) managed by CPU unit 13 constituting PLC system SYS in managed communication unit list 92. It is assumed that the PLC support device 8 is directly connected to one of the communication couplers 52. The PLC support device 8 acquires the product serial number of the connected communication coupler 52, identifies the connected communication coupler 52, and stops IO refresh between the identified communication coupler 52 and the CPU unit 13. An operation screen 94 that accepts an input operation of whether or not is displayed. Further, the PLC support device 8 may display a screen for accepting an input operation as to whether to start IO refresh between the communication coupler 52 and the CPU unit 13.

<H. Modification>
In the description of the above embodiment, the following may be performed.

  In step S <b> 301, upon receiving an IO refresh stop request from the communication coupler 52, the CPU unit 13 stops IO refresh with the communication coupler 52. Here, when the IO refresh stop request is received from the communication coupler 52 in a state where the IO refresh between the CPU unit 13 and the communication coupler 52 is already stopped, the CPU unit 13 indicates that the IO refresh has already been stopped. A signal may be transmitted to the communication coupler 52.

  In step S331, upon receiving an IO refresh start request from the communication coupler 52, the CPU unit 13 starts IO refresh with the communication coupler 52. Here, when an IO refresh start request is received from the communication coupler 52 in a state where the IO refresh between the CPU unit 13 and the communication coupler 52 has already started, the CPU unit 13 has already started the IO refresh. The indicated signal may be transmitted to the communication coupler 52.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 PLC, 2 field network, 3 servo motor driver, 4 servo motor, 5 remote IO terminal, 6 detection switch, 7 relay, 8 PLC support device, 10 connection cable, 11 PLC system bus, 12 power supply unit, 13 CPU unit, 14,53 IO units, 15 special unit, 51 remote IO terminal bus 52 communication coupler 103 refresh stop flag, 105 refresh start flag, 190 communication I / F, 310 storage unit, 320 IO units organized information, 51 1 down link, 51 2-uplink, SYS PLC system.

Claims (9)

A communication unit that functions as a master device and is communicably connected to a plurality of slave devices via a system bus,
The communication unit is communicably connected to the controller arithmetic unit via a network.
The controller communicates with at least one of the communication units via the network, manages whether to enable data input / output processing with the communication unit, and from the communication unit to the communication unit A signal indicating whether to enable data input / output is received via the network,
The communication unit is
A communication unit communicating with the controller via the network;
A receiving unit that receives an input operation of an instruction as to whether or not the controller enables data input / output processing with the communication unit;
A communication unit including a control unit that transmits a signal indicating the instruction received by the reception unit to the controller via the network. The communication unit includes a communication interface for accepting connection of an external information processing apparatus,
In order for the reception unit to receive the input of the instruction, the external information processing apparatus connected by the communication interface determines whether the controller enables data input / output processing with the communication unit. Receiving an input operation, transmitting a signal according to the received input operation to the communication unit, and receiving the transmitted signal by the communication unit,
The communication unit according to claim 1, wherein the control unit transmits a signal corresponding to the input operation received by the external information processing apparatus connected to the controller as a signal indicating the instruction. The accepting unit is a switching member that accepts an instruction as to whether the controller enables data input / output processing with the communication unit by switching on or off,
The communication unit according to claim 1, wherein the control unit transmits a signal corresponding to an input operation received by the switching member to the controller. The controller executes the program periodically or in an event to perform the management target communication unit, event data input / output processing, and periodic data input / output processing. ,
The communication unit performs data input / output processing with the controller according to the cycle, and transmits a signal corresponding to the instruction received by the receiving unit to the controller through the event data input / output processing. The communication unit according to claim 1.   The communication unit according to claim 1, wherein the communication unit is a communication coupler connected to the arithmetic unit of the controller via a field network. Communicates with at least one communication unit via a network, manages whether to enable data input / output processing with the communication unit, and enables data input / output with the communication unit from the communication unit A controller that accepts a signal as to whether or not to perform via the network,
The controller stores unit organization information for managing the communication unit to be managed in a storage unit,
The communication unit functions as a master device, is communicably connected to a plurality of slave devices via a system bus, and communicates with the controller via the network, and the controller inputs data with the communication unit. A reception unit that receives an input operation of an instruction as to whether to enable output processing, and a signal that indicates the instruction that has received the input operation by the reception unit is transmitted to the controller via the network by the communication unit Including a control unit,
The controller receives from the communication unit a signal indicating whether the controller enables data input / output processing with the communication unit via the network;
A controller comprising: an input / output control unit configured to control whether to enable the data input / output processing with the communication unit by updating the unit organization information according to the signal. A communication unit that functions as a master device and is communicably connected to a plurality of slave devices via a system bus, and communicates with at least one of the communication units via a network, and performs data input / output processing with the communication unit A control system comprising a controller that receives a signal as to whether or not to enable via the network,
The controller stores unit organization information for managing the communication unit to be managed in a storage unit,
Wherein the communication unit includes a communication unit that communicates with arithmetic unit of the controller via the network,
A receiving unit that receives an input operation of an instruction as to whether or not the controller enables data input / output processing with the communication unit;
A control unit that transmits a signal indicating the instruction accepted by the accepting unit to the controller via the network to the controller via the network;
The controller is
A receiving unit for receiving, via the network, a signal indicating whether the controller enables data input / output processing with the communication unit from the communication unit;
A control system comprising: an input / output control unit that controls whether or not to enable the input / output processing of the data with the communication unit by updating the unit organization information according to the signal. A communication unit that functions as a master device and is communicably connected to a plurality of slave devices via a system bus, and communicates with at least one of the communication units via a network, and performs data input / output processing with the communication unit A control method of data input / output processing in a control system comprising a controller that receives a signal as to whether to enable or not via the network,
The controller stores unit organization information for managing the communication unit to be managed in a storage unit,
Wherein the communication unit includes a communication unit that communicates with arithmetic unit of the controller via the network,
The control method is:
The communication unit accepting an input operation of an instruction as to whether or not the controller enables data input / output processing with the communication unit;
The communication unit transmits a signal indicating the instruction that has accepted the input operation to the controller via the network by the communication unit;
The controller receives, from the communication unit, a signal indicating whether the controller enables data input / output processing with the communication unit via the network;
The controller includes a step of controlling whether to enable the data input / output processing with the communication unit by updating the unit organization information according to the signal. A program that functions as a master device and controls the operation of a communication unit that is communicably connected to a plurality of slave devices via a system bus,
The communication unit includes a processor and a memory, and includes a communication unit that communicates with the arithmetic unit of the controller via a network.
The controller communicates with at least one of the communication units via the network, manages whether to enable data input / output processing with the communication unit, and from the communication unit to the communication unit A signal indicating whether to enable data input / output is received via the network,
The program receives an input operation of an instruction as to whether or not the controller enables data input / output processing with the communication unit, to the processor;
A program for causing the communication unit to transmit a signal indicating the instruction that has received the input operation in the receiving step to the controller via the network.

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