JP2015022401A - Communication control device, communication control method, and communication control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To optimize a transmission unit of input/output data transmitted between an arithmetic unit and a process input/output device.SOLUTION: A communication control device 2 performs data transmission by memory transfer asynchronously with each other between an arithmetic unit 1 and a plurality of process input/output devices 31. The communication control device comprises: a node number determination unit 27 that determines the number of nodes to be data transfer units with the arithmetic device, from a data size of input/output data and configuration information on the apparatuses connected with the communication control device; an upstream communication control unit 21 that transmits and receives a communication frame including the nodes to/from the arithmetic device; and a downstream communication control unit 24 that transmits and receives the input/output data to/from the plurality of process input/output devices. The downstream communication control unit integrates multiple pieces of input data received from the plurality of process input devices into the nodes the number of which has been determined by the node number determination unit. The upstream communication control unit expands multiple pieces of output data included in the nodes received from the arithmetic unit to the plurality of corresponding process output devices.

Description

  The present invention relates to a communication control device, a communication control method, and a communication control system, and is suitably applied to a communication control device, a communication control method, and a communication control system that transmit data by memory transfer.

  2. Description of the Related Art Conventionally, in a control device including a motion controller that controls the movement of a motor or the like, the motion controller has a configuration in which a CPU directly performs data reading / writing, communication management, and control to a server controller or the like. With such a configuration, there is a problem in that the load on the CPU of the motion controller increases, and the performance of the motion control is squeezed within the control cycle, so that high-speed and stable motion control cannot be performed. In addition, when a large amount of data communication occurs, the data communication process monopolizes the CPU of the motion controller, which affects the motion control.

  Therefore, in Patent Document 1, by having a dual port memory that can be used by the communication controller that controls communication processing and the CPU of the motion controller, the load on the CPU of the motion controller is reduced, and the capacity is increased at high speed. It is possible to exchange data.

JP 2006-350929 A

  By the way, in a general control system such as a power plant, the control data requires immediacy and fixed periodicity. Data is transmitted between them. In such a control system, in order to handle more data, it is necessary to increase the number of process input / output devices. As a method of increasing the process input / output devices, it is conceivable to use a communication control device that controls communication between the arithmetic device and the process input / output device. When the communication control device is used in the control system using the above-described memory transfer, when the number of process input / output devices controlled by one arithmetic device increases, the number of communication increases and the transfer speed decreases. There was a problem.

  The present invention has been made in consideration of the above points, and a communication control device and a communication control method capable of optimizing a transmission unit of input / output data transmitted between an arithmetic device and a process input / output device. And a communication control system.

  In order to solve such a problem, in the present invention, a communication control device that performs data transfer by memory transfer asynchronously with each other between an arithmetic device and a plurality of process input / output devices, the data size of input / output data and the data A node number determination unit that determines the number of nodes as a data transfer unit with the arithmetic device from configuration information of devices connected to the communication control device, and an upstream that transmits and receives a communication frame including the arithmetic device and the node A communication control unit; a plurality of process input / output devices; and a downstream communication control unit that transmits and receives the input / output data. The downstream communication control unit receives a plurality of input data received from a plurality of process input devices in the node The upstream communication control unit integrates a plurality of output data included in the node received from the arithmetic device. The data, characterized in that it expands to a corresponding plurality of process output device, the communication control device is provided.

  According to such a configuration, data transmission by memory transfer is performed asynchronously between the arithmetic device and the plurality of process input / output devices, and the data size of the input / output data and the configuration information of the devices connected to the communication control device Determining the number of nodes as a data transfer unit with the arithmetic device, integrating a plurality of input data received from a plurality of process input devices into the determined number of nodes, and receiving the node from the arithmetic device A plurality of output data included in the data are expanded to a plurality of corresponding process output devices. This optimizes the integration of the input / output data into the communication frame from the data size handled by the data input / output device and the configuration information of the connected device so that communication is not wasted even if the entire system is small. can do.

  According to the present invention, it is possible to prevent a decrease in transfer speed by optimizing the transmission unit of input / output data transmitted between the arithmetic device and the process input / output device to reduce the number of communication of the arithmetic device.

It is a block diagram which shows the structure of the communication control system which concerns on one Embodiment of this invention. It is a conceptual diagram explaining the communication form concerning the embodiment. It is a conceptual diagram explaining the efficiency improvement of the communication frame and transfer memory area | region concerning the embodiment. It is a conceptual diagram explaining the number of nodes concerning the embodiment. It is a conceptual diagram explaining integration of transfer data according to the embodiment. It is a conceptual diagram which shows the flow of the data processing at the time of the data input concerning the embodiment. It is a conceptual diagram which shows the flow of the data processing at the time of the data output concerning the embodiment.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

(1) Configuration of Communication Control System First, the configuration of the communication control system of this embodiment will be described with reference to FIG. As shown in FIG. 1, the communication control system includes an arithmetic device 1, a communication control device 2, and process input devices 31A to 31D (hereinafter, a plurality of process input devices may be collectively referred to as a process input device 31). The process output devices 41A to 41D (hereinafter, a plurality of process output devices may be collectively referred to as the process output device 41), the control object 5, the communication line 6, the communication line 7, the control signal line 8, and the like. Is done.

  In this embodiment, the communication control system is applied to a control system such as a large-scale plant. Examples of the control target 5 include a control target including a turbine, a sensor, and an auxiliary machine.

  The computing device 1 always monitors the state of the controlled object 5 and performs optimal footback control. The process input device 31 converts a signal indicating the state of the control target 5 (hereinafter referred to as input data) into data to be transmitted to the arithmetic device 1. The process output device 41 converts feedback data (hereinafter referred to as output data) transmitted from the arithmetic device 1 into a signal to be transmitted to the controlled object 5.

  The communication control device 2 relays communication between the arithmetic device 1 and the process input device 31 or the process output device 41. The arithmetic device 1 and the communication control device 2 are connected by a communication line 6 which is a serial communication line. The controlled object 5 and the process input device 31 or the process output device 41 are connected by the control signal line 8. By the control signal line 8, input data is transmitted from the control target 5 to the process input device 31, and output data is transmitted from the process output device 41 to the control target 5. A plurality of communication control devices 2 can be connected on the communication line 6 as shown in FIG.

  Further, the communication control device 2 and the process input device 31 or the process output device 41 are connected by the communication line 7. Through the communication line 7, input data is transmitted from the process input device 31 to the communication control device 2, and output data is transmitted from the communication control device 2 to the process output device 41.

  The communication line 6 between the arithmetic device 1 and the communication control device 2 and the communication line 7 between the communication control device 2 and the process input device 31 or the process output device 41 are asynchronously communicated by memory transfer. Is going. As described above, in the control system, immediacy and constant periodicity are required for the transfer of control data, and therefore it is necessary to perform data transmission quantitatively and continuously by periodic memory transfer. In this embodiment, the communication line 6 and the communication line 7 both perform memory transfer at a constant cycle, but data transmission by memory transfer between the communication line 6 and the communication line 7 is performed asynchronously. .

  The communication control device 2 includes an upstream communication control 21, an input buffer 22, an output buffer 23, a downstream communication control 24, a data size setting function 25, a node number determination function 27, and a configuration information acquisition function 26.

  The upstream communication control has a function of communicating with the arithmetic device 1 through the communication line 6. The downstream communication control 24 has a function of communicating with a plurality of process input devices 31 or process output devices 41 via the communication line 7. The input buffer 22 holds input data transmitted from the process input device 31, and the output buffer 23 holds output data to the control target 5 transmitted from the arithmetic device 1.

  The data size setting function 25 has a function of setting the data size of input / output data handled by the process input device 31 and the process output device 31. The configuration information acquisition function 26 has a function of acquiring information on devices connected to the communication control device 2. Further, the node number determination function 27 has a function of determining the number of communication line component units recognized by the computing device 1 based on information from the data size setting function 25 and the configuration information acquisition function 26. A unit of a communication line component recognized by the arithmetic device 1 will be described as a node hereinafter.

(2) Function of Communication Control Device Here, the function of the communication control device 2 will be described. The communication control device 2 takes in the input data transmitted from the process input device 31 by the downstream communication control 24 and holds it in the input buffer 22. The input data held in the input buffer 22 is transmitted to the arithmetic unit 1 via the communication line 6 by the upstream communication control 21. At this time, a plurality of input data are integrated into one node and transmitted to the arithmetic device 1. As described above, a node is a unit of a communication line component recognized by the arithmetic device 1. For this reason, the arithmetic unit 1 recognizes the plurality of input data as one node by integrating the plurality of input data into one node.

  Further, the communication control device 2 takes in the output data transmitted from the arithmetic device 1 via the communication line 6 by the upstream communication control 21 and holds it in the output buffer 23. The output data held in the output buffer 23 is transmitted to the process output device 41 via the communication line 7 by the downstream communication control 24, and is output to the controlled object 5 through the control signal line 8. Similarly to the input data, the output data sent from the arithmetic device 1 also stores a plurality of output data in one node. Therefore, when transmitting from the output buffer 23 to the process output device 4, a plurality of output data stored in one node is expanded to each process output device 41.

  Here, with reference to FIG. 2, the difference between the conventional communication mode and the communication mode of the present invention will be described.

  In the general communication mode of FIG. 2, the arithmetic unit 90 communicates with the process input / output device 31 or 41 on a one-to-one basis. For this reason, one process input / output device is recognized as one node. Here, input / output data is stored one by one in one node. For example, in FIG. 2, input data from the process input device 31 </ b> A is recognized by the arithmetic device 90 as node A, and input data from the process input device 31 </ b> B is recognized as node B. In addition, the output data to the process output device 41A is recognized by the arithmetic unit 90 as the node C, and the output data to the process output device 31B is recognized as the node D.

  On the other hand, in the communication mode according to the present invention, the arithmetic device 1 and the process input / output device 31 or 41 communicate via the communication control device 2. As described above, the communication control device 2 according to the present embodiment integrates a plurality of input data with respect to one node or develops a plurality of output data integrated with one node.

  For example, in FIG. 2, two input data from the process input device 31 </ b> A and the process input device 31 </ b> B are integrated into the node 1. Further, two output data to the process output device 41A and the process output device 41B are integrated in the node 2.

  For this reason, the arithmetic unit 1 can perform communication using a smaller number of nodes than the number of process input / output devices 31 or 41 that are actually connected. The number of nodes is determined by a node number determination function 27 that the communication control apparatus 2 has. The number of nodes is determined based on the size of the input / output data and the configuration information of the devices connected to the communication control device 2. The input / output data size is set by the data size setting function 25 of the communication control device 2. The configuration information is acquired by the configuration information acquisition function 26 of the communication control device 2.

  Next, the efficiency of the communication frame and the transfer memory area will be described with reference to FIG. In conventional communication, a communication control bit is provided before and after one input / output data. For example, when three pieces of input / output data are transmitted, communication control bits are added before and after one piece of input / output data, and a total of six communication control bits must be transmitted together with the three pieces of input / output data. It was.

  However, in this embodiment, by integrating a plurality of input / output data into one node, only two communication control bits need be assigned to the entire integrated data, and communication resources can be saved.

  Further, in the conventional memory transfer, a transfer memory allocation area is set large so that various node sizes and the number of nodes can be accommodated. For this reason, when the node size is small or the number of nodes is small with respect to the allocation area of the transfer memory, the empty area must be transferred and communication loss occurs.

  On the other hand, in the present embodiment, a plurality of input data or output data is integrated into one node, and data is stored in an area that has been conventionally transferred as an empty area, thereby reducing communication loss and transfer efficiency. Can be improved. Further, as described above, the communication control device 2 determines the number of input / output data and the number of nodes to be used based on the size of the input / output data and the configuration information of the devices connected to the communication control device 2. To do. Thereby, the input / output transmission unit between the arithmetic device 1 and the process input / output devices 31 and 41 can be optimized.

  In the present embodiment, as described above, data transmission between the arithmetic device 1 and the communication control device 2 and the communication control device 2, the process input device 31, and the process output device 41 are performed while transferring the control data at regular intervals. By optimizing the data transmission between the control data, the data transmission of the control data is both immediacy and constant periodicity.

  Next, the number of nodes determined by the node number determination function 27 will be described with reference to FIG.

  As shown in FIG. 4, the communication control device 2 holds a data table indicating the number of input / output data integrated into one node and the number of nodes used for each connected device. As described above, the configuration information acquisition function 26 acquires the configuration information of the device connected to the communication control device 2, and selects the data table of the connected device corresponding to the configuration information acquired from the plurality of data tables. When the data size is determined by the data size setting function 25, the number of nodes and the number of data integration suitable for the data size are set.

  The data size is set by the data size setting function 25 according to the input from the system administrator. The data size is fixed according to the characteristics of the control target 5. For example, when the controlled object 5 is temperature, the data size is 8 words, and when the controlled object 5 is in an open / closed state such as a valve, the data size is 1 word. The system administrator selects the data size according to the control target controlled by the arithmetic device 1.

  For example, when the device connected to the communication control device 2 is the connected device 1, and the data size is 1 word by the data size setting function 25, the number of used nodes is 1, and the number of data integrated into one node. It can be seen that is 8 words. Further, when the data size is 4 words, the number of used nodes is 2, the number of data integrations is 2, 2, and it can be seen that two data are integrated into two nodes. Further, when the data size is 8 words, the number of used nodes is 3, the number of data integrations is 2, 3 and 3, and it is understood that 2 data, 3 data, and 3 data are integrated into 3 nodes.

  For example, FIG. 5A shows the first node and the second node when the transfer data size (input / output data size) is 8 words, the number of connected devices is 8, and the data size stored in one node is 30 words. The case where data is integrated into three nodes of the third node is shown. As shown in FIG. 5 (a), data (8 words × 3 units = 24 words) of the process input device 31 or the process output device 41 are integrated into the first node and the second node, and the process is integrated into the third node. Data for two devices of the input device 31 or the process output device 41 (8 words × 2 devices = 16 words) are integrated.

  FIG. 5B shows the first node and the second node when the transfer data size (input / output data size) is 4 words, the number of connected devices is 8, and the data size stored in one node is 30 words. The case where data is integrated into these two nodes is shown. As shown in FIG. 5B, data (4 words × 4 units = 16 words) of four process input devices 31 or process output devices 41 are integrated into the first node and the second node.

  FIG. 5C shows the case where the transfer data size (input / output data size) is 1 word, the number of connected units is 8, and the data size stored in one node is 30 words. The data is integrated into the first node. The case where it is done is shown. As shown in FIG. 5C, data (1 word × 8 units = 8 words) of eight process input devices 31 or process output devices 41 are integrated into the first node.

  In this way, the number of data integration is determined so that data is evenly stored in one or more nodes according to the data size and the data size stored in one node. As described above, in the present embodiment, quantitative and continuous data transmission by memory transfer is realized by referring to a data table in which the integrated number of data is set in advance, and a plurality of data is transmitted to one node. The transfer speed is improved by storing the transfer data of the base and reducing the number of communications.

(3) Communication Control Method Next, a data processing flow at the time of data input and output will be described with reference to FIGS. 6 and 7.

  FIG. 6 is a conceptual diagram showing the flow of data processing at the time of data input. As shown in FIG. 6, the communication control device 2 occupies a plurality of nodes in the process input / output device area in the input buffer 22. A plurality of nodes in the process input / output device area in the input buffer 22 are set by addresses corresponding to an address map in the transfer memory of the arithmetic device 1.

  In FIG. 6, three nodes are occupied in the input buffer 22. For example, as illustrated in FIG. 5A, the number of connected process input devices 31 is 8, the transfer data size is 8 words, and one node is 30 words. In this case, in the data table of FIG. 4, it is set that the data for 8 units are stored in 3 nodes, 3 data, 3 data, and 2 data respectively.

  Accordingly, the eight input data collected by the eight process input devices 31 are transmitted to the downstream communication control 24 via the communication line 7. Then, by the downstream communication control 24, the eight input data are integrated by three data, three data, and two data, and stored in three nodes of the input buffer 22 in the communication control device 2.

  When an input request is transmitted from the arithmetic device 1, the input data stored at the node address occupied by the downstream communication control 24 in the input buffer 22 is transmitted to the arithmetic device 1 via the communication line 6 by the upstream communication control 21. Is done. The arithmetic device 1 performs one-to-one communication with each node of the input buffer 22 in the communication control device 2. Therefore, the arithmetic device 1 stores the input data stored in the three nodes transmitted from the upstream communication control 21 at the address in the transfer memory of the arithmetic device 1 corresponding to the node address of the input buffer 22.

  FIG. 7 is a conceptual diagram showing the flow of data processing during data output. As shown in FIG. 7, the communication control device 2 occupies a plurality of nodes in the process input / output device area in the output buffer 23. A plurality of nodes in the process input / output device area in the output buffer 23 are set by node addresses corresponding to an address map in the transfer memory of the arithmetic device 1.

  In FIG. 7, three nodes are occupied in the output buffer 23. For example, as illustrated in FIG. 5A, the number of connected process output devices 41 is 8, the transfer data size is 8 words, and the node is 30 words. In this case, in the data table of FIG. 4, it is set that the data for 8 units are stored in 3 nodes, 3 data, 3 data, and 2 data respectively.

  At the time of data output, output data is transmitted from the computing device 1 to the node address occupied by the communication control device 2. The upstream communication control 21 of the communication control device 2 stores the output data for three nodes transmitted from the arithmetic device 1 in three nodes of the output buffer 23. Then, the downstream communication control 24 of the communication control device 2 expands the output data for three nodes into eight data and transmits it to the eight process output devices 4. The arithmetic device 1 controls the control object 5 based on the control data output from the process output device 4.

(4) Effects of this Embodiment As described above, according to this embodiment, data transmission by memory transfer is performed asynchronously between the arithmetic device 1 and the plurality of process input / output devices 31 and 41, The number of nodes serving as a data transfer unit with the arithmetic device 1 is determined from the data size of the input / output data and the configuration information of the devices connected to the communication control device 2, and received from the plurality of process input devices 31 and 41. The plurality of input data are integrated into the determined number of nodes, and the plurality of output data included in the nodes received from the arithmetic device 1 are developed on the corresponding plurality of process output devices. This optimizes the integration of input / output data into the communication frame based on the data size handled by the data input / output device and the configuration information of the connected device, so that communication is not wasted even when the entire system is small. can do. In addition, even if the number of connected process I / O devices is increased using a communication control device, it is possible to prevent a decrease in transfer speed by reducing the number of communications of the processing unit, and the communication performance before the process I / O device is expanded. It is possible to expand the system scale while maintaining the above.

DESCRIPTION OF SYMBOLS 1 Arithmetic unit 2 Communication control device 21 Upstream communication control 22 Input buffer 23 Output buffer 24 Downstream communication control 25 Data size setting function 26 Configuration information acquisition function 27 Node number determination function 31 Process input device 41 Process output device 5 Control object 6 Communication circuit 7 Communication line 8 Control signal line

Claims (10)

A communication control device that performs data transfer by memory transfer asynchronously between an arithmetic device and a plurality of process input / output devices,
A node number determination unit that determines the number of nodes as a data transfer unit with the arithmetic device from the data size of input / output data and the configuration information of devices connected to the communication control device;
An upstream communication control unit for transmitting and receiving a communication frame including the computing device and the node;
A downstream communication control unit for transmitting / receiving the input / output data to / from a plurality of process input / output devices;
With
The downstream communication control unit
Integrating a plurality of input data received from a plurality of process input devices into the number of nodes determined by the node number determination unit;
The upstream communication control unit
A communication control device, wherein a plurality of output data included in the node received from the arithmetic device is developed in a plurality of corresponding process output devices. An input buffer that occupies an area for the transfer memory corresponding to the number of nodes determined by the node number determination device;
An output buffer that occupies an area for the transfer memory corresponding to the number of nodes determined by the node number determination device;
With
The downstream communication control unit integrates a plurality of input data received from the plurality of process input devices into the node and stores it in the transfer memory area of the input buffer,
The communication control device according to claim 1, wherein the upstream communication control unit stores the node received from the arithmetic device in the transfer memory area of the output buffer. The downstream communication control unit stores the plurality of input data at successive addresses of the transfer memory area of the input buffer;
The upstream communication control unit stores the node at a continuous address in the area for the transfer memory in the output buffer;
The communication control device according to claim 2, wherein: The communication control device according to claim 1, further comprising a data size setting unit that sets a data size of input / output data transmitted and received by the process input / output device in accordance with an input from an administrator. The communication control apparatus according to claim 1, further comprising a configuration information acquisition unit that is connected to the communication control apparatus and acquires a configuration of a device controlled by the arithmetic device. The node number determination unit refers to a data table in which the input / output data size, the number of nodes, and the number of input / output data integrated into the nodes are associated with each device controlled by the arithmetic device. The communication control apparatus according to claim 1, wherein the number of nodes is determined from a data size of the input / output data and the configuration information. A communication control method in a communication control device for performing data transfer by memory transfer asynchronously with each other between an arithmetic device and a plurality of process input / output devices,
A node number determining unit that determines the number of nodes as a data transfer unit with the arithmetic device, an upstream communication control unit that transmits and receives a communication frame including the arithmetic device and the node, a plurality of process input / output devices, and the input A downstream communication control unit for transmitting and receiving output data,
A first step in which the node number determination unit determines the number of nodes from the data size of the input / output data and the configuration information of the devices connected to the communication control device;
A second step in which the downstream communication control unit integrates a plurality of input data received from a plurality of process input devices into the number of nodes determined by the node number determination unit;
A third step in which the upstream communication control unit develops a plurality of output data included in the node received from the arithmetic device to a plurality of corresponding process output devices;
A communication control method comprising: The communication control device includes an input buffer that occupies an area for a transfer memory corresponding to the number of nodes determined by the node number determination device, and a transfer memory corresponding to the number of nodes determined by the node number determination device An output buffer that occupies an area for
In the second step, the downstream communication control unit integrates a plurality of input data received from the plurality of process input devices into the node and stores the input data in the transfer memory area of the input buffer. Steps,
In the third step, the upstream communication control unit stores the node received from the arithmetic device in the area for the transfer memory of the output buffer;
The communication control method according to claim 7, comprising: In the fourth step, the sixth step in which the downstream communication control unit stores the plurality of input data at successive addresses in the transfer memory area of the input buffer;
In the fifth step, a seventh step in which the upstream communication control unit stores the node at successive addresses in the area for the transfer memory in the output buffer;
The communication control method according to claim 8, comprising: A computing device that controls the device to be controlled;
A plurality of process input / output devices that transmit / receive input / output data to / from the control target device in response to an input / output request from the arithmetic device;
A communication control device for performing data transfer by memory transfer asynchronously with each other between the arithmetic device and the plurality of process input / output devices;
With
The communication control device includes:
From the data size of the input / output data and the configuration information of the device to be controlled, determine the number of nodes as a data transfer unit with the arithmetic device,
In response to an input request from the arithmetic device, a plurality of input data received from a plurality of process input devices are integrated into the determined number of nodes,
In response to an output request from the arithmetic device, a plurality of output data included in the node received from the arithmetic device is developed in a plurality of corresponding process output devices.

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