Control system, relay device, and communication method

Abstract

Provided is a configuration capable of quickly responding to a communication state of a transmission path. The configuration is provided with: a first controller having an interface for connecting to a first transmission path; a second controller having an interface for connecting to a second transmission path; and a relay unit having a first interface to be connected to the first transmission path and a second interface to be connected to the second transmission path. The relay unit has a detection unit that detects the communication state of the first transmission path, and transmits the output data transmitted from the first controller to the second controller in accordance with a transfer setting, and transmits first state data indicating the detected communication state of the first transmission path to the second controller.

Description

Technical Field

[0001] The invention relates to a control system, a relay device and a communication method. Background Art

[0002] With the rapid development of information and communication technology in recent years, the need to process more data in industrial equipment is also increasing. More specifically, technological innovations using communication technologies, such as IoT (Internet of Things) and Industry 4.0, are developing. As a result, the amount of data exchanged within the system is increasing.

[0003] As one of the solutions to the increase in the amount of data to be processed, International Publication No. 2013 / 137023 (Patent Document 1) discloses a structure that enables more appropriate data update between devices in a structure including a plurality of communication lines.

[0004] When multiple controllers are connected to form a network distributed control system, a relay unit is used as a gateway responsible for data forwarding between controllers. In such a network distributed control system, a controller exchanges data with other controllers via the relay unit. Through such data exchange, control status monitoring, control between controllers, etc. are achieved.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 2013 / 137023 Summary of the invention

[0008] Problems to be solved by the invention

[0009] In the above-mentioned network distributed control system, data exchange between controllers is realized via a transmission path and a relay unit, so the control performance or operation rate of the network distributed control system may change according to the communication state of the transmission path. Therefore, in order to maintain the control performance or operation rate of the network distributed control system, a structure that can quickly respond to the communication state of the transmission path is desired.

[0010] Means for solving problems

[0011] A control system of an example of the present disclosure comprises: a first controller having an interface for connecting to a first transmission path; a second controller having an interface for connecting to a second transmission path; and a relay unit having a first interface for connecting to the first transmission path and a second interface for connecting to the second transmission path, the relay unit having a detection unit for detecting the communication status of the first transmission path, the relay unit sending output data sent from the first controller to the second controller according to a forwarding setting, and sending first status data indicating the detected communication status of the first transmission path to the second controller.

[0012] According to the control system, the relay unit detects the communication state of the first transmission path and transmits the data of the communication state to the second controller connected to the second transmission path different from the first transmission path. Thus, the second controller connected to the second transmission path can be included in the device that is notified of the communication state of the first transmission path and can cope with the state.

[0013] In the above control system, the relay unit transmits the output data transmitted from the first controller through periodic communication to the second controller through periodic communication, and transmits the first state data to the second controller through periodic communication.

[0014] According to the control system, the relay unit transmits the communication state of the first transmission path to the second controller by periodic communication. Thus, the communication state of the first transmission path is periodically notified to the second controller.

[0015] In the above control system, the relay unit detects recovery of the communication state indicated by the first state data.

[0016] According to the above control system, the relay unit detects that the communication state of the first transmission path has been restored.

[0017] In the above control system, the relay unit stops transmitting the first state data after detecting the recovery.

[0018] According to the above control system, when the communication state of the first transmission path is recovered, the transmission of the first state data is stopped thereafter.

[0019] In the control system, the first status data indicates the importance of responding to the detected communication status of the first transmission path, and the relay unit transmits information indicating details of the detected communication status of the first transmission path to the second controller through message communication.

[0020] According to the control system, the relay unit can transmit the first status data indicating the importance of responding to the communication status detected in the first transmission path by periodic communication, and transmit information indicating the details of the communication status to the second controller by message communication.

[0021] In the above-mentioned control system, the detection unit also detects the communication status of the second transmission path, and the relay unit also sends the output data sent from the second controller to the first controller according to the forwarding settings, and sends the second status data representing the communication status of the detected second transmission path to the first controller.

[0022] According to the control system, output data can be transmitted bidirectionally between the first controller and the second controller, and data on the communication state of the transmission path connected to one of the first controller and the second controller can be transmitted to the other controller.

[0023] In the above control system, the relay unit transmits the output data transmitted from the second controller through periodic communication to the first controller through periodic communication, and transmits the second state data to the first controller through periodic communication.

[0024] According to the control system, output data can be periodically transmitted bidirectionally between the first controller and the second controller, and data on the communication status of the transmission path connected to one of the first controller and the second controller can be periodically transmitted to the other controller.

[0025] In the above control system, the relay unit detects recovery of the communication state indicated by the second state data.

[0026] According to the above control system, the relay unit can detect that the communication state of the second transmission path has been restored.

[0027] In the above control system, the relay unit stops transmitting the second status data after detecting that the communication status of the second transmission path has recovered.

[0028] According to the above control system, when the communication state of the second transmission path is recovered, the transmission of the second state data is stopped thereafter.

[0029] In the control system, the second state data indicates the importance of responding to the detected communication state of the second transmission path, and the relay unit transmits information indicating details of the detected communication state of the second transmission path to the first controller through message communication.

[0030] According to the control system, the relay unit can transmit the second status data indicating the importance of responding to the communication status detected in the second transmission path by periodic communication, and transmit information indicating the details of the communication status to the first controller by message communication.

[0031] The control system provides a user interface for outputting the first status data and the second status data.

[0032] According to the above control system, the first status data indicating the communication status of the first transmission path and the second status data indicating the communication status of the second transmission path can be provided to the user.

[0033] In the above control system, the relay unit communicates with the communication master connected to the first transmission path via the first transmission path, and communicates with the second controller as the communication master via the second transmission path.

[0034] According to the above control system, the relay unit can operate as a slave device in the communication via the first transmission path and the communication via the second transmission path.

[0035] According to an example of the present disclosure, a relay device is connected to a first controller via a first transmission path, and is connected to a second controller via a second transmission path. The relay device has: a first interface for connecting to the first transmission path; a second interface for connecting to the second transmission path; a detection unit for detecting a communication state of the first transmission path; and a processing circuit for sending output data sent from the first controller to the second controller according to a forwarding setting, and sending first status data indicating the detected communication state of the first transmission path to the second controller.

[0036] The relay device detects the communication state of the first transmission path and transmits the data of the communication state to the second controller connected to the second transmission path different from the first transmission path. Thus, the second controller connected to the second transmission path can be included in the device that is notified of the communication state of the first transmission path and can cope with the state.

[0037] According to an example of the present disclosure, a communication method is a communication method implemented by a control system, the control system having: a first controller having an interface for connecting to a first transmission path; and a second controller having an interface for connecting to a second transmission path. The communication method has the following steps: detecting a communication state of the first transmission path; sending output data sent from the first controller to the second controller according to a forwarding setting; and sending first status data indicating the communication state of the first transmission path to the second controller.

[0038] When the communication method is implemented, if the communication state of the first transmission path is detected, data of the detected communication state is sent to a second controller connected to a second transmission path different from the first transmission path. Thus, the second controller connected to the second transmission path can be included in the device that is notified of the communication state of the first transmission path and can cope with the state.

[0039] Effects of the Invention

[0040] According to the present disclosure, a device that is notified of the communication state of the first transmission path and can respond to the state can include a second controller connected to a second transmission path different from the first transmission path, thereby providing a structure that can quickly respond to the communication state of the transmission path. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram showing an application example of the control system 1 according to the present embodiment.

[0042] Figure 2 It is a schematic diagram showing an overall configuration example of the control system 1 according to the present embodiment.

[0043] Figure 3 1 is a block diagram showing a hardware configuration example of the calculation unit 100 of the main control device 10 according to the present embodiment.

[0044] Figure 4 It is a block diagram showing a hardware configuration example of the calculation unit 200 of the sub-controller 20 according to the present embodiment.

[0045] Figure 5 This is a block diagram showing a hardware configuration example of the relay unit 250 of the sub-controller 20 according to the present embodiment.

[0046] Figure 6 This is a diagram showing an example of the currently occurring event information 265 according to this embodiment.

[0047] Figure 7 This is a diagram showing an example of the currently occurring event information 265 according to this embodiment.

[0048] Figure 8 This is a diagram showing an example of the currently occurring event information 265 according to this embodiment.

[0049] Fig. 9 It is a schematic diagram showing an outline of data communication in the control system 1 according to the present embodiment.

[0050] Fig.10 This is a schematic diagram showing an example of a data structure used for data communication in the control system 1 according to the present embodiment.

[0051] Fig.11This is a diagram for explaining the processing in the relay unit 250 of the control system 1 according to this embodiment.

[0052] Fig.12 This is a diagram for explaining the I / O data transmission based on periodic communication in the control system 1 according to this embodiment.

[0053] Fig.13 This is a diagram showing an example of the data structure according to this embodiment.

[0054] Fig.14 This is a diagram for explaining the event management according to this embodiment.

[0055] Fig.15 This is a diagram for explaining the event management according to this embodiment.

[0056] Fig.16 This is a diagram for explaining the event management according to this embodiment.

[0057] Fig.17 This is a diagram showing an example of the user interface according to this embodiment.

[0058] Fig.18 This is a flowchart showing an example of the registration process of the event information of the relay unit 250 according to this embodiment.

[0059] Fig.19 This is a flowchart showing an example of the deletion and release process of the relay unit 250 according to this embodiment. Detailed Embodiment

[0060] Embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the same or corresponding parts in the drawings are denoted by the same reference numerals and their description will not be repeated.

[0061] <A. Application Example>

[0062] First, an example of the scenario to which the present invention is applied will be described.

[0063] Figure 1 This is a schematic diagram showing an application example of the control system 1 according to this embodiment. Referring to Figure 1 The control system 1 that can constitute a distributed control system includes a first controller and a second controller. The first controller has an interface for connecting to the first transmission path. The second controller has an interface for connecting to the second transmission path.

[0064] The control system 1 further includes a relay unit having a first interface for connecting to the first transmission path and a second interface for connecting to the second transmission path. The relay unit has a module of a gateway and a module for detecting the communication status of the first transmission path. The relay unit sends the output data sent from the first controller to the second controller according to the forwarding setting, and sends the first status data indicating the communication status of the detected first transmission path to the second controller. For example, the relay unit sends the output data sent from the first controller by periodic communication to the second controller by periodic communication, and sends the first status data to the second controller by periodic communication. Such a relay unit is configured to be able to implement the message communication described later.

[0065] In this specification, "detecting the communication status of the transmission path" means detecting whether a predetermined type of specific event has occurred in the transmission path or the relay unit. The specific event is not limited, and includes, for example, different types of events such as communication timeout and inability to start communication. The occurrence of an event means that, for example, such an abnormality has occurred in the communication of the transmission path, but the event is not limited to the abnormality. The communication status of the transmission path includes a state in which an event has occurred and a state in which an event has not occurred. The state in which an event has not occurred is a concept that includes a state in which the event has been eliminated and restored from a state in which the event has occurred.

[0066] In this specification, "cyclic communication" is a method of transmitting predetermined data at predetermined transmission cycles (for example, 1 msec to several hundred msec).

[0067] In this specification, "message communication" is a method of transmitting data in response to a request from a transmission source or a transmission destination. In "message communication", data may be transmitted even when data transmission is requested.

[0068] pass Figure 1 The data sent by the periodic communication shown has a relatively high priority and a relatively small amount of data. In contrast, the data sent by the message communication has a relatively low priority and a relatively large amount of data. In this way, in addition to the periodic communication as a high-frequency data exchange method, the message communication without time limit can also be used.

[0069] In this specification, the terms "input data" and "output data" indicate what the object data means from the perspective of the controller concerned.

[0070] More specifically, "input data" refers to data input to the controller of interest (data referenced by the controller of interest). "Input data" includes, for example, command values ​​provided from other controllers, state values ​​obtained by sensors connected to other controllers, and the like.

[0071] On the other hand, “output data” refers to data output by the unit concerned (data whose value is changed by the unit concerned). “Output data” includes, for example, command values ​​provided to other controllers and / or actuators connected to other controllers.

[0072] exist Figure 1 In the configuration example shown, data is transferred from the first controller to the second controller via the relay unit. Even the same data may be viewed as "output data" from the first controller as the transmission source, and may be viewed as "input data" from the second controller as the transmission destination.

[0073] In the following description, “input data” and “output data” may be collectively referred to as “input-output data” or “I / O data.” However, “input-output data” and “I / O data” may include only input data or only output data.

[0074] In the control system 1 of the present embodiment, it is possible to arbitrarily set which of the periodic communication and the message communication is to be used, in accordance with the characteristics of the transmission target data and the like.

[0075] Thus, in the control system 1, the following structure is adopted: not only does the relay unit send the output data sent from the first controller to the second controller (forwarding process), but the relay unit also detects the communication state of the first transmission path (detection process), and notifies the second controller of the first state data indicating the detected state (notification process). By adopting such a structure, the relay unit can send a "state notification" indicating the communication state of the first transmission path to the second controller connected to the second transmission path different from the first transmission path. Thus, the second controller connected to the second transmission path can be included in the device that can respond to the event indicated by the communication state of the first transmission path. Thus, in the control system 1, a structure is provided that can quickly change the communication state of the first transmission path to a recovery state.

[0076] In the present disclosure, the first status data indicating the communication status of the first transmission path may be transmitted by periodic communication or message communication. However, in the present embodiment, the status data indicating the communication status of the transmission path is transmitted by periodic communication.

[0077] Furthermore, the first status data indicating the communication status of the first transmission path may be sent not only to the second controller but also to the first controller. Similarly, the second status data indicating the communication status of the second transmission path may be sent not only to the first controller but also to the second controller.

[0078] Hereinafter, as a more specific application example, the detailed configuration and processing of the control system 1 including the relay unit of the present embodiment will be described.

[0079] <B. Overall Structure Example>

[0080] Next, an overall structure example of the control system 1 of the present embodiment will be described.

[0081] Figure 2 is a schematic diagram showing an overall structure example of the control system 1 of the present embodiment. Refer to Figure 2 , the control system 1 of the present embodiment includes a main control device 10 and one or more sub-control devices 20.

[0082] In this specification, the "main control device" and the "sub-control device" are distinctions for ease of explanation, and may be substantially the same hardware structure or substantially the same functional structure. The main control device and the sub-control device may also be a type of computer such as a PLC (programmable logic controller).

[0083] The main control device 10 is connected to one or more sub-control devices 20 via a field network 4. The field network 4 supports periodic communication and message communication. As the field network 4, for example, EtherCAT (registered trademark), EtherNet / IP (registered trademark), PROFINET (registered trademark), PROFIBUS (registered trademark), DeviceNet (registered trademark), FL-net, CompoNet (registered trademark), etc. can also be used.

[0084] In this way, the main control device 10 corresponds to the first controller, and it has an interface for connecting to the field network 4 corresponding to the first transmission path.

[0085] The main control device 10 includes an arithmetic unit 100 that performs control operations. The arithmetic unit 100 can perform data communication based on the field network 4. The main control device 10 may also have a power supply unit, an I / O unit, a special unit, etc.

[0086] The sub-control device 20 includes an arithmetic unit 200 that performs control operations and a relay unit 250 that performs data communication using the field network 4. The sub-control device 20 may also have a power supply unit, an I / O unit, a special unit, etc.

[0087] The arithmetic unit 200 is connected to the relay unit 250 via an internal bus 6 (refer to Figure 4 and Figure 5 ). In addition, when the sub-control device 20 includes an I / O unit and / or a special unit, this unit is also connected via the internal bus 6.

[0088] In this way, the arithmetic unit 200 corresponds to the second controller, and it has an interface for connecting to the internal bus 6 corresponding to the second transmission path.

[0089] The relay unit 250 relays the data sent from the main control device 10 in a manner that can be referred to by the arithmetic unit 200, and relays the data output by the arithmetic unit 200 in a manner that can be sent to the main control device 10. That is, the relay unit 250 is a gateway having a first interface for connecting to the field network 4 (the first transmission path) and a second interface for connecting to the internal bus 6 (the second transmission path).

[0090] The control system 1 may also include a support device 300 for creating and changing programs or settings executed by the main control device 10 and / or the sub-control device 20, etc., and a display 400 mainly providing a monitor function. The support device 300 and the display 400 may be connected to the arithmetic unit 200 of the sub-control device 20 or the arithmetic unit 100 of the main control device 10.

[0091] <C. Example of hardware structure>

[0092] Next, an example of the hardware structure of the main devices of the control system 1 of the present embodiment will be described.

[0093] (c1: Arithmetic unit 100)

[0094] Figure 3 is a block diagram showing an example of the hardware structure of the arithmetic unit 100 of the main control device 10 of the present embodiment. Referring to Figure 3 , the arithmetic unit 100 includes a processor 102 such as a CPU (Central Processing Unit) or an MPU (Micro-Processing Unit), a chipset 104, a memory 106, a timer 107, a storage 108, an upper network interface 110, a USB (Universal Serial Bus) interface 112, a memory card interface 114, and a field network interface 120.

[0095] The processor 102 reads various programs stored in the storage 108, expands and executes them in the memory 106, thereby implementing the processing required in the arithmetic unit 100. The chipset 104 controls data communication between the processor 102 and each component, etc.

[0096] Typically, a system program 131 and a user program 132 containing computer-readable codes required for control operations are stored in the storage 108.

[0097] By executing the programs stored in the storage 108, the arithmetic unit 100 as a computer executes the processing described in this specification, and the functional structure described in this specification is implemented in the arithmetic unit 100 as a computer.

[0098] The host network interface 110 controls data communication with other devices via the host network. The USB interface 112 controls data communication with the support device 300 or the display 400 via a USB connection.

[0099] The memory card interface 114 is configured to allow the memory card 116 to be attached and detached, and is capable of writing data to the memory card 116 and reading various data (user programs, trace data, etc.) from the memory card 116 .

[0100] The field network interface 120 controls data communication with the sub-controller 20 via the field network 4. More specifically, the field network interface 120 includes: a receiving buffer 121 for holding received data; a sending buffer 122 for generating data to be sent, etc.; and a counter 123. The field network interface 120 is connected to one or more field devices 90 via the network 5. The field device 90 includes an actuator that exerts a certain physical action on a manufacturing device or a production line, etc., and an input / output device including a sensor that exchanges information with the field. The data exchanged between the sub-controller 20 and the field device 90 via the network 5 is updated in an extremely short cycle of several hundred μsec to several tens of msec.

[0101] The counter 123 is used as a time reference for managing the time of the communication processing via the network 5 or the field network 4. The counter 123 typically increments or decrements the counter value at each predetermined cycle. As the counter 123, for example, a free-running counter is applied, but it can also be implemented using a high-precision event timer (HPET: High Precision Event Timer) or the like, or it can also be implemented using a dedicated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field-Programmable Gate Array: Field Programmable Gate Array). The timer 107 is a counter that provides the current time to the processor 102 or the like.

[0102] (c2: operation unit 200)

[0103] Figure 4 2 is a block diagram showing a hardware configuration example of the arithmetic unit 200 of the sub-controller 20 according to the present embodiment. Figure 4 The computing unit 200 includes a processor 202 such as a CPU or an MPU, a chipset 204, a memory 206, a timer 207, a storage 208, a host network interface 210, a USB interface 212, a memory card interface 214, a field network controller 215, and an internal bus interface 220.

[0104] The processor 202 reads various programs stored in the storage 208, expands and executes them in the memory 206, thereby realizing the processing required by the arithmetic unit 200. The chipset 204 controls data communication and the like between the processor 202 and various components.

[0105] The memory 208 typically stores a system program 231 and a user program 232 including a computer-readable code required for control operations.

[0106] By executing the program stored in the memory 208 , the arithmetic unit 200 as a computer executes the processing described in the present specification, and the functional configuration described in the present specification is implemented in the arithmetic unit 200 as a computer.

[0107] The host network interface 210 controls data communication with other devices via the host network. The USB interface 212 controls data communication with the support device 300 or the display 400 via a USB connection.

[0108] The memory card interface 214 is configured to be able to attach and detach the memory card 216 , and is capable of writing data to the memory card 216 and reading various data (user programs, trace data, etc.) from the memory card 216 .

[0109] The internal bus interface 220 controls data communication with one or more units (including the relay unit 250) via the internal bus 6. More specifically, the internal bus interface 220 includes a reception buffer 221 for holding received data and a transmission buffer 222 for generating data to be transmitted.

[0110] The internal bus 6 supports periodic communication and message communication similarly to the field network 4. As the internal bus 6, a manufacturer-specific communication method may be used, for example, EtherCAT (registered trademark), EtherNet / IP (registered trademark), PROFINET (registered trademark), PROFIBUS (registered trademark), DeviceNet (registered trademark), FL-net, CompoNet (registered trademark), etc. may also be used.

[0111] The field network controller 215 includes: a receiving buffer 221 for holding received data; a sending buffer 222 for generating data to be sent, etc.; and a counter 223, which is a counter for managing communication via the network 5 and has the same function as the counter 123 ( Figure 4 ) The field network controller 215 is connected to one or more field devices 90 via the network 5. The field network controller 215 has the same structure as Figure 3 The field network interface 120 is the same as that of the field network interface 120, so the description is not repeated. Figure 3 The timer 107 is also a counter that provides the current time to the processor 202, etc.

[0112] (c3: relay unit 250)

[0113] Figure 5 2 is a block diagram showing a hardware configuration example of the relay unit 250 of the sub-controller 20 according to the present embodiment. Figure 5 The relay unit 250 includes a processing circuit 260 , a field network interface 270 , and an internal bus interface 280 .

[0114] The processing circuit 260 implements the processing and functions of the relay unit 250 described later. More specifically, the processing circuit 260 includes a processor 262, a memory 264, and a storage 267. The processor 262 reads out the system program (firmware) stored in the storage 267, expands and executes it in the memory 264, thereby implementing the processing required in the relay unit 250. In addition to the system program, the memory 267 also stores a forwarding setting 268 for realizing data forwarding, status information 269, an event log 287, a time setting 289, and an event management program 288. The relay unit 250 implements event management processing, event registration processing, etc. by executing the event management program 288. The event management processing includes the elimination and release processing described later.

[0115] The forwarding setting 268 includes setting items for data forwarded from the operation unit 200 to the main control device 10 and setting items for data forwarded from the main control device 10 to the operation unit 200. Such setting items include identifiers of data to be forwarded, etc. In addition, the forwarding setting 268 may include items for setting the type of state to be sent to the operation unit 200 or the main control device 10 among various communication states detected in the transmission path (field network 4 or internal bus 6). These setting items can be set by user operation, for example.

[0116] The field network interface 270 controls data communication between the main control device 10 and the sub-control device 20 via the field network 4. More specifically, the field network interface 270 includes: a detection unit 271 that detects the communication status of the field network 4; a buffer 272 that includes a buffer for holding received data and a buffer for generating data to be sent, etc.; and a counter 273. The counter 273 has a Figure 3 The counter 123 shown in the figure manages the time related to the data communication via the field network 4.

[0117] The internal bus interface 280 controls data communication via the internal bus 6 with one or more units (including the arithmetic unit 200). More specifically, the internal bus interface 280 includes: a detection unit 281 that detects the communication state of the internal bus 6; a buffer 282 that includes buffers for holding received data and buffers for generating data to be transmitted, etc.; and a counter 283. The counter 283 has the same structure as the Figure 3 counter 123 shown, and manages the time related to data communication via the internal bus 6.

[0118] (c4: Other structures)

[0119] In Figure 3 to Figure 5 , a structural example of providing required functions by a processor executing a program is shown, but a dedicated hardware circuit (such as an ASIC or FPGA, etc.) can also be used to install part or all of these provided functions.

[0120] In this specification, the "processor" is not limited to a narrow sense processor that executes processing in a stored program manner, and also includes hardwired circuits such as ASICs or FPGAs. Therefore, the term "processor" can also be replaced by a processing circuitry pre-defined with processing by computer-readable code and / or hardwired circuits.

[0121] The main part of the arithmetic unit can also be implemented using hardware that follows a general architecture (such as an industrial personal computer based on a general personal computer). In this case, virtualization technology can also be used to execute multiple OSs (Operating System) with different uses in parallel, and execute required applications on each OS.

[0122] (c5: Support device 300 and display 400)

[0123] As an example, the support device 300 and the display 400 of this embodiment are composed of a general computer that follows a general architecture, etc. The hardware structure example of a general computer is well-known, so no detailed description will be given.

[0124] <D. Management of time synchronization and communication state>

[0125] The relay unit 250 performs time synchronization with the arithmetic unit, and in addition, the relay unit 250 detects the communication state.

[0126] (d1: Time synchronization)

[0127] In the present embodiment, "time synchronization" is implemented between the operation unit 200 and the relay unit 250 connected to the operation unit 200 via the internal bus 6. In addition, "time synchronization" is implemented between the operation unit 200 and the operation unit 100 connected to the operation unit 200 via the field network 4. Time synchronization means synchronizing timers, time data, etc. that are mutually possessed. Through such time synchronization, the count value counted by the counter 283 of the internal bus interface 280 is synchronized with the time counted by the timer 207 of the operation unit 200. In addition, the count value counted by the counter 273 of the field network interface 270 is synchronized with the time counted by the timer 107 of the operation unit 100.

[0128] (d2: Detection of communication status)

[0129] The detection unit 281 is implemented by a program (firmware) executed by a processor circuit such as an ASIC or FPGA (not shown) possessed by the internal bus interface 280. Specifically, by executing the program, the detection unit 281 detects the communication state of the internal bus 6. Specifically, the occurrence of an event in the communication is detected, and an event code identifying the detected event is output to the processing circuit 260. As an event, the detection unit 281 detects a timeout based on the communication of the internal bus 6, or detects that the communication cannot be started based on the communication data of the internal bus 6 or the data from the processing circuit 260. In addition, whenever the processing circuit 260 inputs an event code of an event occurring in the communication state of the internal bus 6 from the detection unit 281, the input event code is compared with the event code detected so far, and when it is determined based on the comparison result that there is an event that is no longer detected, that is, when it is detected that the event is eliminated, the event code identifying the eliminated event is obtained.

[0130] In addition, the detection unit 271 is implemented by a program (firmware) executed by a processor circuit such as an ASIC or FPGA (not shown) possessed by the field network interface 270. Specifically, by executing the program, the detection unit 271 detects the communication state of the field network. Specifically, the occurrence of an event in the communication is detected, and an event code 31 described later for identifying the detected event is output to the processing circuit 260. As an event, the detection unit 271 detects a timeout based on the communication of the field network 4, or detects that the communication cannot be started based on the communication data of the field network 4 or the data from the processing circuit 260. In addition, whenever the processing circuit 260 inputs an event code of an event occurring in the communication state of the field network 4 from the detection unit 271, the input event code is compared with the event code detected so far, and when it is determined based on the comparison result that there is an event that is no longer detected, that is, when it is detected that the event is eliminated, the event code identifying the eliminated event is obtained.

[0131] The occurrence event information 265 described below is stored in the memory 264 of the relay unit 250. In addition, the status information 269 of the memory 267 has a plurality of event codes and the status corresponding to each event code. The status information 269 has a data structure capable of retrieving the status corresponding to the event based on the event code. In the present embodiment, "status" represents the importance of the corresponding event. The importance represents the degree of influence of the event on communication, or represents the degree of necessity for coping with the communication status indicated by the event, or represents the degree of urgency for coping. Thus, the higher the importance represented by the status, the higher the necessity or urgency for coping with the corresponding event.

[0132] <E. An example of the occurrence event information 265>

[0133] Figure 6 、 Figure 7 and Figure 8 are diagrams showing an example of the occurrence event information 265 of the present embodiment. Figure 6 represents the basic structure of the record 266 of the present embodiment. Refer to Figure 6 , the occurrence event information 265 has, for example, a table-like structure capable of registering 10 records 266. The record 266 representing the detailed information of the event includes an entry number 30, an event code 31, the importance 32 of the event indicated by the event code 31, and an elimination flag 33 indicating whether the elimination of the event has been detected. The importance 32 corresponding to the status is not limited. For example, it is divided into 5 stages of flags F1 to F5. The flag F1 corresponds to a failure level that causes the entire control system 1 to stop operating for the corresponding event, indicating the highest importance. The flag F2 corresponds to a failure level that causes a part of the control system 1 to stop operating for the corresponding event, indicating the second highest importance. The flag F3 represents an importance lower than that of the flag F2. For example, it indicates that the corresponding event conforms to a mild failure level. The flag F4 represents an importance lower than that of the flag F3. For example, it indicates that the corresponding event conforms to the level of monitoring information. The flag F5 represents an importance lower than that of the flag F4. For example, it indicates that the corresponding event conforms to general information. When registering the record 266 in the occurrence event information 265, the elimination flag 33 of the record 266 is set to "1". When the event elimination is detected for the corresponding event, the elimination flag 33 of the record 266 is set to "0", that is, changed from "1" to "0". In addition, based on the importance determined for the event, any one of the flags F1 to F5 is set to "1". The number of records 266 that can be registered in the occurrence event information 265 is 10, but it is not limited to this number.

[0134] As Figure 7 shown, the record 266 of the occurrence event information 265 can be configured to be in Figure 6Append the time data 34 indicating the time when the event is detected to the information. The time data 34 indicates the time based on the counter value output from either the counter 273 or the counter 283 when the event indicated by the event code 31 is detected. In the present embodiment, the counter that provides the counter value as the basis for the time data 34 can be specified by the time setting 289 based on a user operation received from the support device 300 or the like.

[0135] In the record 266, as the time when such an event is detected, as Figure 8 shown, it may also include the first time data 35 based on the output of the counter 273 and the second time data 36 based on the output of the counter 283.

[0136] The structure of the record 266 registered in the in - progress event information 265 can be adopted, for example, by a user operation received from the support device 300 or the like, as any one of the structures Figure 6 to Figure 8 shown. Hereinafter, the record 266 has, for example, Figure 7 or Figure 8 the structure.

[0137] <F. Data Communication>

[0138] Next, the data communication in the control system 1 of the present embodiment will be described.

[0139] Fig. 9 is a schematic diagram showing an overview of the data communication in the control system 1 of the present embodiment. Fig. 9 Shows an example of the transmission of I / O data between the main control device 10 and the arithmetic unit 200.

[0140] Referring to Fig. 9 , a relay unit 250 is arranged as a gateway between the main control device 10 and the arithmetic unit 200. A field network 4 equivalent to the first transmission path is connected between the main control device 10 and the relay unit 250.

[0141] It is assumed that the output data of the main control device 10 is sent to the arithmetic unit 200 via the relay unit 250 and the output data of the arithmetic unit 200 is sent to the main control device 10 via the relay unit 250. In the present embodiment, for any transmission, either a method based on periodic communication or a method based on message communication can be adopted.

[0142] In a normal control system, I / O data is only sent through periodic communication, but in the present embodiment, either periodic communication or message communication can also be selected according to the amount of data to be sent and the required timeliness, etc.

[0143] The data (output data) transmitted from the main control device 10 is transmitted to the relay unit 250. The relay unit 250 transmits the data received as the output data of the main control device 10 to the calculation unit 200 as the input data of the calculation unit 200.

[0144] On the other hand, data (output data) transmitted from the operation unit 200 is transmitted to the relay unit 250. The relay unit 250 transmits the data received as the output data of the operation unit 200 to the main control device 10 as input data of the main control device 10.

[0145] In this way, the relay unit 250 forwards data between the main control device 10 and the computing unit 200. That is, the relay unit 250 forwards data according to the forwarding setting 268 ( Figure 5 ), the output data sent from the main control device 10 (first controller) through periodic communication is sent to the operation unit 200 (second controller), and the relay unit 250 sends the output data sent from the main control device 10 through message communication to the operation unit 200.

[0146] Likewise, the relay unit 250 transmits the output data sent from the arithmetic unit 200 by periodic communication to the main control device 10 according to the forwarding setting 268 , and transmits the output data sent from the arithmetic unit 200 by message communication to the main control device 10 .

[0147] At this time, the relay unit 250 may also transmit the output data transmitted from the main control device 10 by periodic communication to the operation unit 200 by periodic communication, and transmit the output data transmitted from the main control device 10 by message communication to the operation unit 200 by message communication. Alternatively, the method of transmitting data from the main control device 10 to the relay unit 250 and the method of transmitting data from the relay unit 250 to the operation unit 200 may be different.

[0148] In periodic communication, data is transmitted at every predetermined transmission cycle, so the latest data can always be used at the transmission destination.

[0149] Fig.10 This is a schematic diagram showing an example of a data structure used for data communication in the control system 1 according to the present embodiment.

[0150] Reference Fig.10 In the field network 4, a communication frequency band is divided in each transmission cycle. Each transmission cycle includes a periodic communication frequency band 12 and a message communication frequency band 14. In the periodic communication frequency band 12, a frame 16 of a predetermined data size is transmitted. The frame 16 is sequentially forwarded between devices (units) connected to the field network 4. Thus, the frame 16 circulates periodically in the field network 4.

[0151] In the periodic communication frequency band 12, an area is prepared for writing output data to each device connected to the field network 4. Fig.10 , an example is shown in which N areas are prepared for N devices to write output data respectively. A device connected to the field network 4 can refer to data stored in areas other than the area for writing data of the device itself (ie, data written by other devices).

[0152] Furthermore, in the periodic communication frequency band 12, in addition to the area for writing output data, an area for storing management information (communication management information 18) necessary for communication of the control system 1 is prepared.

[0153] In addition, the frame 16 of the periodic communication frequency band 12 is also prepared with an area for storing the importance 32 of each event registered in the ongoing event information 265. The relay unit 250 writes the importance 32 of the ongoing event information 265 in the memory 264 into the frame 16 received from one transmission path of the internal bus 6 and the field network 4, and transmits the frame 16 to the other transmission path of the internal bus 6 and the field network 4. Thus, the importance 32 of each ongoing event circulates periodically between the devices (units) connected to the field network 4. Through such circulation, the devices (units) connected to the field network 4 can receive the importance 32 of the ongoing event.

[0154] On the other hand, the message communication frequency band 14 is used for message communication from the designated device to one or more other devices according to the instruction of the device (e.g., called "communication master device" or "master device") that manages the field network 4. In addition, in message communication, data with a larger size than that transmitted in one periodic communication may be transmitted, so that one data transmission may require multiple periodic communication frequency bands.

[0155] In addition, in the internal bus 6, Fig.10 Similarly, the communication frequency band is divided for each transmission cycle, and each transmission cycle includes a periodic communication frequency band and a message communication frequency band.

[0156] In this embodiment, an area is prepared in the message communication frequency band 14 for the relay unit 250 to store the ongoing event information 265. The controller (main control device 10 or operation unit 200) receives the ongoing event information 265 from the relay unit 250 through message communication. Thus, the controller can obtain the ongoing event information 265 indicating the event details indicated by the importance 32 in the periodically received frame 16 through message communication.

[0157] Fig.11This is a diagram for explaining the processing in the relay unit 250 of the control system 1 of the present embodiment. In Fig.11 it mainly shows the data forwarding processing in the relay unit 250.

[0158] Referring to Fig.11 the relay unit 250 includes a field network interface 270 connected to the field network 4 and an internal bus interface 280 connected to the internal bus 6.

[0159] The buffer 272 of the field network interface 270 has a receive buffer 274 and a transmit buffer 275. The receive buffer 274 holds the data received from the main control device 10, and the transmit buffer 275 holds the data to be sent to the main control device 10.

[0160] The buffer 282 of the internal bus interface 280 has a receive buffer 284 and a transmit buffer 285. The receive buffer 284 holds the data received from the arithmetic unit 200, and the transmit buffer 285 holds the data to be sent to the arithmetic unit 200.

[0161] The relay unit 250 copies the data held in the receive buffer 274 of the field network interface 270 to the transmit buffer 285 of the internal bus interface 280, and copies the data held in the receive buffer 284 of the internal bus interface 280 to the transmit buffer 272 of the field network interface 270.

[0162] The relay unit 250 realizes data forwarding through such data copying between buffers.

[0163] <G. I / O Data Transmission Based on Periodic Communication>

[0164] Next, the I / O data transmission based on periodic communication in the control system 1 of the present embodiment will be described.

[0165] Fig.12 This is a diagram for explaining the I / O data transmission based on periodic communication in the control system 1 of the present embodiment. Fig.12 It shows the frame 16A that periodically circulates in the field network 4 and the frame 16B that periodically circulates in the internal bus 6.

[0166] Fig.12 (A) of shows a processing example for realizing data transmission from the main control device 10 to the arithmetic unit 200. Referring to Fig.12 (A) of, the main control device 10 writes output data to the area allocated to the frame 16A. Then, the frame 16A is sent to the relay unit 250.

[0167] The relay unit 250 extracts the output data of the main control device 10 included in the frame 16A, and writes the extracted output data of the main control device 10 to the area allocated to the frame 16B. That is, the frame 16B includes the output data of the main control device 10 as the output data of the relay unit 250. In addition, the relay unit 250 writes the importance 32 corresponding to each event of the event information 265 in the frame 16B. Then, the frame 16B is sent to the operation unit 200. The operation unit 200 extracts the output data of the relay unit 250 (the output data of the main control device 10) included in the frame 16B as input data.

[0168] Fig.12 (B) shows an example of processing for realizing data transmission from the sub-control device 20 to the main control device 10. Fig.12 At (B), the operation unit 200 writes the output data to the area allocated to the frame 16B. Then, the frame 16B is transmitted to the relay unit 250.

[0169] The relay unit 250 extracts the output data of the operation unit 200 included in the frame 16B, and writes the extracted output data of the operation unit 200 to the area allocated to the frame 16A. That is, the frame 16A includes the output data of the operation unit 200 as the output data of the relay unit 250. At this time, the relay unit 250 writes the importance 32 corresponding to each event of the event information 265 in the frame 16A. Then, the frame 16A is sent to the main control device 10. The main control device 10 extracts the output data of the relay unit 250 (the output data of the operation unit 200) included in the frame 16A as input data.

[0170] like Fig.12 As shown, the relay unit 250 realizes I / O data transmission based on periodic communication by exchanging (copying) data between the frame 16A that cyclically circulates in the field network 4 and the frame 16B that cyclically circulates in the internal bus 6 .

[0171] Fig.11 and Fig.12 The exchange (copy) of data in the relay unit 250 shown is to exchange (copy) the importance 32 of each event stored in the frame 16 together with the output data of the frame 16. Thus, the importance 32 of each event occurring is also cyclically circulated in the internal bus 6 and the field network 4.

[0172] In the control system 1 providing the above communication environment, the relay device 250 communicates with the communication master connected to the field network 4 and communicates with the arithmetic unit 200 as the communication master connected to the internal bus 6 in the communication via the internal bus 6 .

[0173] <H. Processing of Events>

[0174] Refer to Figure 13 to Figure 16 , and the event processing based on the relay unit 250 will be described. Fig.13 It is a diagram showing an example of the data structure of the present embodiment. Fig.14 It is a diagram for explaining the event management of the present embodiment. In the present embodiment, as Fig.14 shown, when the relay unit 250 detects the occurrence of an event, it registers the record 266 of the information based on the detected event in the in-occurrence event information 265, and registers the log data 40 of the information based on the detected event in the event log 287. The event log 287 is configured to accumulate the log data 40 for each detected event, so the history of the events that have occurred is represented by the event log 287.

[0175] Refer to Fig.13 In (A) of, the record 266 of the in-occurrence event information 265 includes the entry number 30, the importance 32 with the flag F3 indicating "1", the event code 31, the cancellation flag 33, and the time data 34. The event code 31 includes the event number indicating the setting abnormality and the details indicating the input (IN) data irregularity as the detailed information of the event. The event code 31 includes the transmission path identifier 31a for identifying the transmission path where the event is detected.

[0176] Refer to Fig.13 In (B) of, the event log 287 includes one or more log data 40 accumulated in a record form. The log data 40 includes the number identifying the log data 40 and the information of the detected event. The information of this event includes the importance 32, the event code 31, and the time data 34. When a record 266 of the information based on the detected event is newly registered in the in-occurrence event information 265 upon detecting an event, Fig.13 in (A) of, simultaneously, the log data 40 of the information based on this event is registered in the event log 287. Fig.13 in (B) of.

[0177] The relay unit 250 performs cancellation and解除 processing on the in-occurrence event information 265. Refer to Fig.15 , the relay unit 250 performs cancellation and解除 processing when it detects the cancellation of an event or receives a解除 operation.

[0178] When the relay unit 250 detects the cancellation of an event, based on the event code indicated by this detection, it retrieves the record 266 having the event code 31 that is the same as this event code from the in-occurrence event information 265, and sets the cancellation flag 33 of the retrieved record 266 to "0". Thus, this record 266 in the in-occurrence event information 265 is set to indicate that the event has been cancelled.

[0179] When receiving the release operation, the relay unit 250 retrieves the record 266 having the event code 31 that matches the event code from the ongoing event information 265 based on the event code indicated by the release operation. When it is determined that the deletion flag 33 of the retrieved record 266 is set to "0", the relay unit 250 deletes the record 266 from the ongoing event information 265. In addition, when the deletion flag 33 of the retrieved record 266 indicates "1", that is, when the event deletion has not been detected, the relay unit 250 does not delete the record 266 from the ongoing event information 265.

[0180] In this way, the record 266 of the ongoing event information 265 is deleted from the ongoing event information 265 when the cancellation of the event is instructed (operated) after the elimination of the corresponding event is detected. Fig.16 The specific processing flow is shown in FIG. Fig.16 In the example, event (1) occurs at time T1, and a record 266 of event (1) is registered in the ongoing event information 265. Event (2) occurs at time T2 thereafter, and a record 266 of event (2) is registered in the ongoing event information 265.

[0181] At a later time T3, when the elimination of event (1) is detected, the elimination flag 33 of event (1) is set to "0", but the record 266 is not deleted and is retained. At a later time T4, when the cancellation operation of event (1) is accepted, the elimination flag 33 based on event (1) is set to "0", and the record 266 is deleted from the occurring event information 265.

[0182] At the subsequent time T5, when the elimination of event (2) is detected, the elimination flag 33 of event (2) is set to "0", but the record 266 is not deleted and is retained. At the subsequent time T6, the release operation of event (2) is accepted. At this time, the elimination flag 33 of event (2) is set to "0", so based on the accepted release operation, the record 266 is deleted from the occurring event information 265.

[0183] according to Fig.16 When the occurrence of an event is detected, the information of the event is registered in the occurring event information 265 and the event log 287. When the elimination of the event registered in this way is detected and the release operation is subsequently accepted, the information of the event is deleted from the occurring event information 265 while being retained in the event log 287.

[0184] Thus, when an event is "detected and eliminated" and then "released", the event information (record 366) is deleted from the ongoing event information 265, and the periodic transmission of the importance 32 corresponding to the event is stopped.

[0185] <I. Example of User Interface>

[0186] Fig.17 This is a diagram showing an example of the user interface of the present embodiment. Devices such as the main control device 10 or the sub-control device 20 display the importance 32 of events received through periodic communication or the ongoing event information 265 received through message communication. For example, the device forwards the importance 32 of the event and the ongoing event information 265 to the support device 300 or the display 400 connected to the device for display. Fig.17 For example, an example of the screen 350 displayed on the display of the support device 300 is shown. The display 400 can also display a Fig.17 similar screen. The provision structure of such a user interface is not limited to the structure provided using the tools of the support device 300 or the display 400.

[0187] Fig.17 The screen 350 contains information for dealing with ongoing events. In the screen 350, based on each record 266 of the ongoing event information 265, it includes the order 351 corresponding to the item number 30, the importance 352 corresponding to the importance 32, the category 352A and the event name 353 based on the event code 31, the occurrence time 354 based on the time data 34, the cause 355, and the response 356. The cause 355 represents the estimated cause (factor) of the event occurrence, and the response 356 represents the information for dealing with the event based on this cause. The support device 300 retrieves the corresponding estimated cause and response information from the pre-determined information based on the event code 31 of the ongoing event information 265. Thus, the information of the cause 355 and the response 356 is obtained. The response 356 may include, for example, the information 357 of the corresponding page of the user manual for troubleshooting.

[0188] The screen 350 also includes buttons 359 and 360 that are operated to accept user operations. The button 359 is a cancel operation button and is operated when canceling an ongoing event. When the support device 300 or the display 400 accepts the operation of the button 359, it forwards the instruction of the cancel operation including the event code to the relay unit 250. Thus, the relay unit 250 can accept the cancel operation of the event. The event code included in such a cancel operation, for example, includes the event code of the event specified by the user's touch operation on the Fig.17 screen 350.

[0189] Operate the operation button 360 to set one or both of the first time based on the counter value of the counter 273 and the second time based on the counter value of the counter 283 as the time of the record 266 registered in the in-occurrence event information 265. Through such a user operation, the setting of the time is forwarded to the relay unit 250 and saved as the time setting 289.

[0190] In addition, such a user interface may also be configured to: accept a user operation on the Fig.17 screen to switch the time 354 of each event to the display of one of the first time and the second time, or to switch to the display of both.

[0191] The screen of such a user interface may be configured to include a screen that only displays the importance 352 corresponding to each in-occurrence event received through periodic communication, and a screen based on the in-occurrence event information 265 received through message communication Fig.17 of.

[0192] <J. Processing Flowchart>

[0193] Next, a processing example implemented by the relay unit 250 in the control system 1 of the present embodiment will be described.

[0194] Fig.18 It is a flowchart showing an example of the registration process of the event information of the relay unit 250 of the present embodiment. Fig.19 It is a flowchart showing an example of the deletion and解除 processing of the relay unit 250 of the present embodiment. Fig.18 and Fig.19 The respective steps shown can also be implemented by the processor 262 of the relay unit 250 executing the event management program 288.

[0195] Referring to Fig.18 , the relay unit 250 determines whether the communication state of the field network 4 has detected a pre-determined state, such as a state in which an event such as a pre-determined abnormality occurs (step S2). If the state in which an event occurs is detected (step S2: Yes), the relay unit 250 creates a record 266 of event information based on the event code indicating the detected event. The relay unit 250 obtains the time (the first time, the second time, or both times) set by the time setting 289 and sets it as the time data 34 of the record 266 (step S4). Then, the relay unit 250 registers the created record 266 in the in-occurrence event information 265 (step S6), and performs logging (step S8). That is, the relay unit 250 creates log data 40 based on the above event information and registers it in the event log 287. Then, it transfers to step S10.

[0196] If it is detected that the communication state of the field network 4 is not in a state where an event is occurring (step S2 : No), the processing of steps S4 to S8 is skipped and the flow proceeds to step S10 .

[0197] The relay unit 250 determines whether the communication state of the internal bus 6 detects a predetermined state, such as a state where an event such as a predetermined abnormality occurs (step S10). If the state where an event occurs is detected (step S10: yes), the process of steps S4 to S8 is performed on the event detected in the communication state of the internal bus 6. That is, a record 266 of event information based on an event code representing the event is created (step S4), the record 266 is registered in the event information 265 that is occurring (step S6), and the log data 40 based on the event information is created and registered in the event log 287 (step S8). Then, the process moves to step S2.

[0198] On the other hand, when it is detected that the communication state of the internal bus 6 is not a state in which an event has occurred (step S10: No), the processing of steps S4 to S8 is skipped and the process moves to step S2, and the processing of subsequent steps S2 to S10 is repeatedly performed in the same manner as described above.

[0199] Reference Fig.19 The relay unit 250 determines whether the event elimination is detected or the release operation is accepted based on the communication status of the field network 4 or the internal bus 6 (step S20).

[0200] If it is determined that the event elimination is not detected and the release operation is not accepted (step S20: No), the process of step S20 is repeatedly performed. If it is determined that the event elimination is detected (step S24: Yes), the relay unit 250 retrieves the record 266 having the event code 31 that matches the event code from the event information 265 that is currently occurring based on the event code of the event whose elimination is detected (step S26). The relay unit 250 sets the elimination flag 33 of the retrieved record 266 to "0" (step S28).

[0201] If it is determined in step S20 that a release operation has been accepted (step S30: Yes), the relay unit 250 retrieves a record 266 having an event code 31 that matches the event code from the ongoing event information 265 based on the event code represented by the accepted release operation (step S32). The relay unit 250 determines whether the deletion flag 33 of the retrieved record 266 is set to "0" (step S34). If it is determined that the deletion flag 33 of the record 266 is set to "0" (step S34: Yes), the relay unit 250 deletes the record 266 from the ongoing event information 265 (step S36). Then, the process returns to step S20, and the relay unit 250 repeatedly implements the subsequent processing in the same manner as described above.

[0202] When it is determined that the event cancellation is not detected (step S24: No), the process proceeds to step S30. Further, when it is determined that the cancellation operation is not understood (step S30: No), or when it is determined that the cancellation flag 33 of the retrieved record 266 is not set to "0" (step S34: No), the process returns to step S20.

[0203] <K Note>

[0204] The present embodiment as described above includes the following technical ideas.

[0205] [Structure 1]

[0206] The control system (1) has:

[0207] A first controller (100) having an interface (120) for connecting to a first transmission path (4);

[0208] A second controller (200) having an interface (220) for connecting to a second transmission path (6); and

[0209] A relay unit (250) including a first interface (270) for connecting to the first transmission path and a second interface (280) for connecting to the second transmission path,

[0210] The relay unit has a detection unit (271) for detecting the communication state of the first transmission path,

[0211] The relay unit transmits the output data sent from the first controller to the second controller according to the forwarding setting (268), and transmits first status data (265) indicating the detected communication state of the first transmission path to the second controller.

[0212] [Structure 2]

[0213] In the control system described in Structure 1,

[0214] The relay unit transmits the output data sent from the first controller through periodic communication to the second controller through periodic communication, and transmits the first status data to the second controller through periodic communication.

[0215] [Structure 3]

[0216] In the control system described in Structure 1 or 2,

[0217] The relay unit detects the recovery of the communication state indicated by the first status data.

[0218] [Structure 4]

[0219] In the control system described in Structure 3,

[0220] The relay unit stops transmitting the first status data after detecting the recovery.

[0221] [Structure 5]

[0222] In the control system described in any one of structures 1 to 4,

[0223] The first state data indicates the importance of responding to the communication state detected by the first transmission path (32).

[0224] The relay unit transmits information (265) indicating details of the detected communication state of the first transmission path to the second controller through message communication.

[0225] [Structure 6]

[0226] In the control system described in any one of structures 1 to 5,

[0227] The detection unit further detects a communication state of the second transmission path.

[0228] The relay unit further transmits the output data transmitted from the second controller to the first controller according to the forwarding setting, and transmits second status data (265) indicating the detected communication status of the second transmission path to the first controller.

[0229] [Structure 7]

[0230] In the control system described in structure 6,

[0231] The relay unit transmits the output data transmitted from the second controller through periodic communication to the first controller through periodic communication, and transmits the second status data to the first controller through periodic communication.

[0232] [Structure 8]

[0233] In the control system described in structure 6 or 7,

[0234] The relay unit detects recovery of the communication state indicated by the second state data.

[0235] [Structure 9]

[0236] In the control system described in structure 8,

[0237] The relay unit stops transmitting the second status data after detecting recovery of the communication status indicated by the second status data.

[0238] [Structure 10]

[0239] In the control system described in any one of structures 6 to 8,

[0240] The second status data indicates the importance of responding to the communication status detected by the second transmission path (32).

[0241] The relay unit transmits information (265) indicating details of the detected communication state of the second transmission path to the first controller through message communication.

[0242] [Structure 11]

[0243] In the control system described in any one of structures 6 to 10,

[0244] The control system provides a user interface that outputs the first status data and the second status data.

[0245] [Structure 12]

[0246] In the control system described in any one of structures 1 to 11,

[0247] The relay unit communicates with a communication host device connected to the first transmission path via the first transmission path, and communicates with the second controller serving as the communication host device via the second transmission path.

[0248] [Structure 13]

[0249] A relay device (250) is connected to a first controller (100) via a first transmission path (4) and is connected to a second controller (200) via a second transmission path (6), wherein the relay device (250) comprises:

[0250] a first interface (270), which is used to connect to the first transmission path;

[0251] a second interface (280) for connecting to the second transmission path;

[0252] a detection unit (271) for detecting a communication state of the first transmission path; and

[0253] A processing circuit (260) transmits output data transmitted from the first controller to the second controller according to a forwarding setting (268), and transmits first status data (265) indicating a detected communication status of the first transmission path to the second controller.

[0254] [Structure 14]

[0255] A communication method is implemented by a control system (1), the control system (1) comprising: a first controller (100) having an interface (120) for connecting to a first transmission path (4); and a second controller (200) having an interface (220) for connecting to a second transmission path (6), wherein the communication method comprises the following steps:

[0256] detecting a communication status of the first transmission path;

[0257] sending the output data sent from the first controller to the second controller according to the forwarding setting (268); and

[0258] First state data (265) indicating the communication state of the first transmission path is transmitted to the second controller.

[0259] The embodiments disclosed this time should be considered in all respects as illustrative and non-restrictive. The scope of the present invention is indicated by the claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0260] Description of symbols

[0261] 1: control system; 4: field network; 6: internal bus; 10: main control device; 12: frequency band for periodic communication; 14: frequency band for message communication; 16, 16A, 16B: frame; 18: communication management information; 20: sub-control device; 30: item number; 31: event code; 32, 352: importance; 33: elimination flag; 34: time data; 35: first time data; 36: second time data; 90: field device; 100, 200: operation unit; 102, 202, 262: processor; 104, 204: chipset; 106, 206, 264 : Memory; 107, 207: Timer; 108, 208, 267: Storage; 110, 210: Host network interface; 112, 212: Interface; 114, 214: Memory card interface; 116, 216: Memory card; 120, 270: Field network interface; 121, 221, 274, 284: Receive buffer; 122, 222, 275, 285: Send buffer; 123, 223, 273, 283: Counter; 131, 231: System program; 132, 232: User program; 215: Field network controller; 220, 280:

[0262] Internal bus interface; 250: relay unit; 260: processing circuit; 265: information on events occurring; 266: record; 268: forwarding setting; 269: status information; 271, 281: detection unit; 272, 282: buffer; 287: event log; 288: event management program; 289: time setting; 300: support device; 350: screen; 351: sequence; 352A: category; 353: event name; 354, T1, T2, T3, T4, T5, T6: time; 355: cause; 356: response; 358, 359, 360: button; 400: display; F1, F2, F3, F4, F5: flag.

Claims

1. A control system, wherein: The control system has: A first controller having an interface for connecting to a first transmission path; a second controller having an interface for connecting to a second transmission path; as well as a relay unit having a first interface for connecting to the first transmission path and a second interface for connecting to the second transmission path, The relay unit includes a detection unit for detecting a communication state of the first transmission path. The relay unit transmits the output data transmitted from the first controller to the second controller according to the forwarding setting, and transmits first status data indicating the detected communication status of the first transmission path to the second controller.

2. The control system according to claim 1, wherein: The relay unit transmits the output data transmitted from the first controller through periodic communication to the second controller through periodic communication, and transmits the first status data to the second controller through periodic communication.

3. The control system according to claim 1 or 2, wherein: The relay unit detects recovery of the communication state indicated by the first state data.

4. The control system according to claim 3, wherein: The relay unit stops transmitting the first status data after detecting the recovery.

5. The control system according to any one of claims 1 to 4, wherein: The first status data indicates the importance of responding to the communication status detected by the first transmission path. The relay unit transmits information indicating details of the detected communication state of the first transmission path to the second controller through message communication.

6. The control system according to any one of claims 1 to 5, wherein: The detection unit further detects a communication state of the second transmission path. The relay unit further transmits the output data transmitted from the second controller to the first controller according to the forwarding setting, and transmits second status data indicating the detected communication status of the second transmission path to the first controller.

7. The control system according to claim 6, wherein: The relay unit transmits the output data transmitted from the second controller through periodic communication to the first controller through periodic communication, and transmits the second status data to the first controller through periodic communication.

8. The control system according to claim 6 or 7, wherein: The relay unit detects recovery of the communication state indicated by the second state data.

9. The control system according to claim 8, wherein: The relay unit stops transmitting the second status data after detecting the recovery of the communication status indicated by the second status data.

10. The control system according to any one of claims 6 to 8, wherein: The second status data indicates the importance of responding to the communication status detected by the second transmission path. The relay unit transmits information indicating details of the detected communication state of the second transmission path to the first controller through message communication.

11. The control system according to any one of claims 6 to 10, wherein: The control system provides a user interface that outputs the first status data and the second status data.

12. The control system according to any one of claims 1 to 11, wherein: The relay unit communicates with a communication host device connected to the first transmission path via the first transmission path, and communicates with the second controller serving as the communication host device via the second transmission path.

13. A relay device connected to a first controller via a first transmission path and connected to a second controller via a second transmission path, wherein: The relay device has: A first interface, which is used to connect to the first transmission path; a second interface, which is used to connect to the second transmission path; a detection unit configured to detect a communication state of the first transmission path; as well as The processing circuit transmits the output data transmitted from the first controller to the second controller according to the forwarding setting, and transmits first status data indicating the detected communication status of the first transmission path to the second controller.

14. A communication method implemented by a control system, the control system comprising: a first controller having an interface for connecting to a first transmission path; and a second controller having an interface for connecting to a second transmission path, wherein: The communication method has the following steps: detecting a communication status of the first transmission path; sending the output data sent from the first controller to the second controller according to the forwarding setting; as well as The first status data indicating the communication status of the first transmission path is transmitted to the second controller.

Images