JP2010049543A - Programmable controller, input/output device and operation parameter access system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a programmable controller that increases the flexibility of connection of a support apparatus for accessing operation parameters for operation of a controlled apparatus, in a system including a programmable controller and an input/output device for data input/output to/from a controlled apparatus. <P>SOLUTION: The programmable controller includes: a first request sending part for, when a request specifying an operation parameter is received from the support apparatus, converting the request and sending the converted request to the input/output device; a second request sending part for, when a first response indicating whether the converted request has been received normally is received from the input/output device, sending a read request instructing the input/output device to read out a processing result to the request; and a processing result sending part for, when a second response including the processing result information, which is a response to the read request, is received from the input/output device, converting the second response and sending it to the support apparatus. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for accessing (reading / writing / changing) an operation parameter that determines an operation of a device to be controlled.

  A programmable controller (hereinafter referred to as “PLC”) calculates and executes a sequence control program, and controls an apparatus to be controlled through an input / output device connected to a system bus or a dedicated network.

  The PLC has a data communication interface of several words to several thousand words that requires high speed response of about several tens of μs to several ms and constant periodicity of about several ms, with the input / output device. It has a communication interface for data (command message, etc.) of several thousand words or more that requires a response of several tens of ms to several hundreds of ms and does not require a constant periodicity.

The input / output device is a device that exchanges data with a control target device. Examples of input / output devices include servo amplifiers and inverters.
The functions of the input / output device include reading / writing / changing operation parameters for operating the control target device, real-time trace function for monitoring the operation state when incorporated in the machine / device, and personal data for historical trace. There is a trend graph display function for displaying on a computer display.

FIG. 9 is a diagram showing a conventional system configuration.
As shown in FIG. 9, this conventional system includes a PLC 51 and a plurality of input / output devices (servo amplifiers, inverters, etc.) 52. The PLC 51 and the plurality of input / output devices 52 are connected by a dedicated network (IO / bus) 53, and the input / output device dedicated support device (hereinafter simply referred to as “support device”) 54 is connected to the plurality of input / output devices 52. Are directly connected. The input / output device 52 and the support device 54 communicate with each other using a dedicated protocol. Hereinafter, such a connection form between the input / output device 52 and the support device 54 is referred to as “direct connection”.

As shown in FIG. 9, the input / output device 52 includes a dedicated support device data processing unit 55 and an I / O bus interface unit 56.
The dedicated support device data processing unit 55 includes a transmission buffer 57, a request message analysis unit 58, and a response message transmission unit 59.

  In the following, among the functions of the input / output device 52, the operation parameter read / write / change function will be mainly handled. This is done by transmitting a command message (request) (sometimes referred to as a “request message”) corresponding to reading, writing, or changing operation parameters from the support device 54 to the input / output device 52.

  When the request message is received, the input / output device 52 performs command analysis on the request message by the request message analysis unit 58 as shown in FIG. Response data corresponding to the command processing indicated by the request message is transmitted to the support device 54 by the response message transmission unit 59.

  However, it is difficult to find the input / output device (servo amplifier, inverter, etc.) in the place where the control target equipment is installed, so it is difficult to find, and the above-described support device 54 is directly connected to the input / output device 52. Making it difficult. In order to reduce the load of installation work, it is desirable to allow connection forms other than direct connection with the input / output device 52 (hereinafter referred to as “indirect connection”), and to increase the degree of freedom of the connection form.

Further, the dedicated network interface IC has a problem that the scale of the IC has increased in recent years due to the addition of functions, and the manufacturing cost has increased.
On the other hand, as described above, the input / output device 52 can perform response processing for a request message in one communication. However, such processing is supported only by a protocol when the support device 54 and the input / output device 52 are directly connected.

As a peripheral technology, for example, Patent Document 1 discloses a programmable controller that performs command response communication with a host computer. In response to the read command received from the host computer, the programmable controller creates and returns a response including the corresponding read data and the reliability of the data.
Japanese Patent Laid-Open No. 2-176905

  The present invention is a system composed of a programmable controller and an input / output device for inputting / outputting data to / from the control target device, and the degree of freedom of the connection form of the support device for accessing the operation parameters for operating the control target device. It is an object of the present invention to provide a programmable controller, an input / output device, and an operation parameter access system that can expand the range.

  The proposed programmable controller is connected to the input / output device for controlling the control target device via the first communication means, and is connected to the input / output device via the support device and the second communication means. Connected further. And this programmable controller has a 1st request | requirement transmission part, a 2nd request | requirement transmission part, and a process result transmission part.

  The first request transmission unit converts a request command for requesting the setting of the operation parameter from the support device into a first command in a format in which the first communication means can communicate, and transmits the first command to the input / output device. To do.

The second request transmission unit transmits a second command for acquiring a processing result of the input / output device for the first command.
When the processing result transmission unit receives a processing response including the processing result in response to the second command from the input / output device, the processing result transmission unit converts the processing response into a format in which the second communication unit can communicate. It transmits to the said support apparatus.

  The proposed input / output device is connected to the programmable controller by the first communication means, and controls the control target device via the programmable controller. The input / output device includes a first response transmission unit, a response processing unit, and a second response transmission unit.

  The first response transmission unit transmits an acceptance response indicating acceptance of the first command to the programmable controller when receiving the first command requesting the setting of the operation parameter from the programmable controller.

The response processing unit performs processing according to the first command.
The second response transmission unit transmits a processing response including the processing result to the programmable controller when receiving a second command for requesting transmission of the processing result of the response processing unit from the programmable controller.

  According to the proposed system composed of programmable controller and input / output device, connect the support device to the programmable controller instead of connecting the support device to the communication interface for the support device that the input / output device has (dedicated to the input / output device) The support device communicates a request to the input / output device via the programmable controller. As a result, when connecting the support device, the location of the input / output device (servo amplifier, inverter, etc.) that is hardly noticeable in the place where the control target device is installed is found, and it is freed from the trouble of cabling at that location. It is possible to reduce the load of connection work of the support device.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1A is a diagram showing a schematic configuration of an operation parameter access system according to an embodiment of the present invention.

  As shown in FIG. 1A, this system includes a PLC 1 and a plurality of input / output devices (servo amplifiers, inverters, etc.) 2-1, 2-2,. The PLC 1 and the plurality of input / output devices 2-1, 2-2,... Are connected by a dedicated network (IO / bus) 3.

  On the other hand, the PLC 1 and the support device 4 are connected by a general-purpose network (RS232C, USB, Ethernet (registered trademark), etc.) 6. The dedicated network 3 and the general-purpose network 6 are both physically cables.

  Conventionally, the communication between the PLC 1 and the plurality of input / output devices 2-1, 2-2,... Has only a passive communication function in which each input / output device responds to the command message of the PLC 1. In this embodiment, a communication protocol corresponding to the dedicated network 3 is used between the PLC 1 and the plurality of input / output devices 2-1, 2-2,... (At least one of them). Implement. Although only one device is shown in the figure, a communication function using a command message is implemented between the support device (at least one of them), for example, the support device 4 in the figure, with the PLC 1. .

  As a result, not only direct connection but also indirect connection can be supported as a connection form of the support device that accesses the operation parameters for operating the control target device, and the degree of freedom of the connection form of the support device can be expanded.

This point will be specifically described subsequently.
In the direct connection which is the conventional connection method, the input / output device is mounted with a protocol (response message transmission unit 59 in FIG. 9) for actively transmitting the completion of processing when the command message from the PLC is completed. It was. That is, the command processing of the input / output device in the direct connection can be said to be a command response type in which processing completion for the command from the support device is returned.

  On the other hand, in the indirect connection that is the main point of this system, the input / output device receives a command from the support device via the dedicated network (I / O bus) 3 having the PLC as a relay point, as will be described later. Execute. The input / output device is only equipped with a command acknowledge type (acknowledgment notification type) protocol that returns a command acceptance when a command is received, and has a notification means for actively notifying completion of command processing. It has not been. For this reason, in the indirect connection, even if the input / output device completes the processing of the command after receiving the command, the input / output device cannot notify the support device of the completion of the processing.

  In this way, in order to allow an I / O device with a limited protocol that can only return an acknowledgment for a command to send a command processing completion, a command processing completion is sent. When the input / output device receives the second command to be urged, the command processing completion may be transmitted.

  In order to realize this, in this system, the PLC 1 that has received the request command from the support device 4 converts the request command into the format of the dedicated network (I / O bus) 3 that connects the PLC 1 and the input / output device. The first command of the conversion result is transmitted to the input / output device. The input / output device that has received the first command returns an acceptance response indicating that the first command has been accepted. Receiving this acceptance response, the PLC 1 transmits a second command for prompting transmission of information on the completion of command processing to the input / output device after a lapse of a predetermined time considering the command processing time of the input / output device. The input / output device that has received the second command returns a processing response indicating the processing result of the first command. (The command processing result by the input / output device is held in a read packet response unit 49 in FIG. 1B described later when the command processing is completed. When the input / output device receives the second command, the read packet is received. It is assumed that the data held in the response unit 49 is transmitted.) The PLC 1 that has received this processing response converts the processing response into the format of the general-purpose network 6 that connects the PLC 1 and the support device 4 to the support device 4. Send.

  As a result, the completion of command processing can be transmitted even by an input / output device with a limited protocol that can only return an acknowledge for the command.

FIG. 1B is a diagram showing a detailed configuration of the operation parameter access system of FIG.
As illustrated in FIG. 1B, the support device 4 is connected to the PLC 1 via the general-purpose network 6. The communication device selection allows the support device 4 to select either a communication mode to be used by directly connecting to the input / output device or indirectly connecting to the input / output device via the PLC instead of being connected directly. When connected directly to the input / output device, the communication unit 12 communicates with the input / output device. When connected indirectly to the input / output device, the indirect communication unit 13 communicates with the input / output device. Have.

  When the support device performs communication by indirectly connecting with the input / output device, a destination indicating a communication partner is generally designated. Therefore, the PLC 1 that receives a message to the input / output device earlier than the input / output device is connected to the input / output device as in this embodiment. When the communication protocol of the network 3 to be connected is different from that of the network 6 to which the support device 4 is connected, a protocol conversion function between the networks is required.

  The PLC 1 collects and registers configuration information of each input / output device, and a protocol conversion unit 22 that performs conversion between data on the general-purpose network 6 and data on the dedicated network (IO / bus) 3. , A transceiver 23 which is a communication interface with the support device 4 connected to the general-purpose network 6, a system work memory 24, a user data memory 25, a user program memory 26, and data transmission / reception processing and data transfer with the input / output device An IO / bus interface unit 27 that performs processing and the like is included. These are connected to each other by an internal bus 28.

  The system work memory 24 stores data related to a system program executed by a CPU (not shown). The user program memory 26 stores user programs. The user data memory 25 stores data used in the user program.

  The configuration information management unit 21 includes a configuration information collection unit 31 that collects configuration information of input / output devices connected to the dedicated network 3, and a configuration information registration unit 32 that registers a part of the collected configuration information in a table.

  The protocol conversion unit 22 includes a request message reception unit 33 that receives a request message from the support device 4 via the general-purpose network 6, a message conversion unit 34 that converts the received request message into a command packet, and a response message to the support device 4. A response message transmission unit (also referred to as “process result transmission unit”) 35 to be transmitted, and a command packet transmission unit (““ 36 ”, a first response receiving unit 37 that receives a first response to the transmitted command packet, and a read packet that instructs to read out the processing result of the process requested by the command packet. A read packet transmission unit (also referred to as “second request transmission unit”) that transmits to a destination input / output device, for example, the input / output device 2-1. ) 38, having a second response receiving unit 39, for receiving a second response to the transmitted read packet.

The input / output device 2-1 includes a dedicated support device data processing unit 41 and an I / O bus interface unit 42.
The dedicated support device data processing unit 41 is a unit for processing a request message from the directly connected support device 5, and includes a transmission buffer 43, a request message analysis unit 44, and a response message transmission unit 45.

  When the input / output device 2-1 receives the request message from the support device 5, the request message is analyzed by the request message analysis unit 44 as in the conventional example of FIG. 9, and a plurality of messages are stored in the transmission buffer 43. Of the response data, the response data corresponding to the command processing indicated by the received request message is transmitted to the support device 5 by the response message transmission unit 45.

  The I / O bus interface unit 42 is a unit for processing a command packet and a read packet corresponding to a request message from the indirect connection support device 4, and analyzes the received packet to obtain configuration information. Received packet analysis unit 46 that determines whether the packet is a collected packet (described later), a command packet, or a read packet, and sends configuration information packet having configuration information of itself (input / output device that received the configuration information collection packet) to PLC 1 A configuration information response unit 47, a command packet response unit (also referred to as “first response transmission unit”) 48, and a read packet response unit (also referred to as “second response transmission unit”) 49.

In the present embodiment, each of the above units is realized by hardware such as an IC chip.
Further, when a request message is transmitted via the PLC 1 in order to read, write, change, or the like of an operation parameter with respect to an input / output device having the support device 4, the input / output device of the PLC 1 uses the command of the present embodiment. It is necessary to know whether the packet is supported. For this reason, the PLC 1 sends configuration information collection packets to the input / output devices connected to the dedicated network 3 in advance or periodically, so that the configuration information (the input / output device identification information (station number), Flag information (device type information) indicating whether or not the output device can also support data from an indirectly connected support device, data size that can be received by the input / output device at a time, and the like) are collected. This collection process will be described next.

FIG. 2 is a flowchart of the configuration information collection process. This process is executed by the PLC 1, the configuration information collection unit 31 and the configuration information registration unit 32 of the PLC 1.
In step S <b> 1 of FIG. 2, the configuration information collection packet is transmitted from the PLC 1 to the dedicated network (IO / bus) 3. The configuration information collection packet is received by the IO / bus interface unit of each input / output device connected to the IO / bus 3.

  If the IO / bus interface unit of the input / output device that has received the configuration information collection packet does not support a communication protocol that can receive the configuration information collection packet, the IO / bus interface unit of the input / output device receives the received configuration information. Discard the collected packet.

  When the IO / bus interface unit of the input / output device that has received the configuration information collection packet supports the configuration information collection packet, the configuration information of the input / output device itself is set by the configuration information response unit 47 of the input / output device. The configuration information packet is transmitted to the PLC 1.

  The PLC 1 that has received the configuration information packet in step S2 refers to the flag information included in the received configuration information packet by the configuration information collection unit 31 in step S3, and the input / output device is connected to the indirect connection support device. It is determined whether or not the data can be supported.

  If it is determined in step S3 that the input / output device can also handle data from the indirect connection support device (if the determination in step S3 is Yes), the configuration information registration unit 32 receives the data in step S4. The station number information included in the configuration information packet is registered in the indirect connection target table shown in FIG. 3, and the series of processes is terminated. In the table of FIG. 3, there is an impression that the station numbers are registered as serial numbers, but in reality, only the station numbers of the support devices corresponding to the indirect connection are registered.

  On the other hand, if it is determined in step S3 that the input / output device cannot cope with data from the indirectly connected support device (if the determination in step S3 is No), the series of processes is immediately terminated.

Actually, steps S2, S3, and S4 are executed by the number of input / output devices that have received the configuration information collection packet.
Next, a case where a request message is transmitted from the support device 4 to the input / output device through the PLC 1 will be described with reference to FIGS.

In this case, the request message transmitted from the support device 4 to the PLC 1 is converted into a command packet in the PLC 1 and transmitted to the input / output device.
FIG. 4 is a diagram showing a request message and a command packet which is a conversion result of the request message.

In FIG. 4, the request message is composed of items “processing status”, “connection method”, “connection ID”, “command”, “data”, and “BCC”.
“Processing status” indicates whether or not the processing was normally performed at the time of reception response. A value such as “FF” is set as the initial value, and processing results such as “data cannot be interpreted”, “normally processed”, “the input / output device itself is not operating normally”, etc. A value for identifying (including) is set on the input / output device side and returned to the support device 4.

  Specifically, if the first response received by the PLC indicates something other than a normal reception processing result such as “data cannot be interpreted” or “the input / output device itself is not operating normally” Immediately, a response message including the contents is created and returned to the support device 4. When the first response received by the PLC indicates a normal reception processing result, a response message including the content of the second response is created at the time when the second response is received, and the support device 4 Will be replied to.

  In the “connection method”, this message is transmitted from the support device directly connected to the input / output device to the input / output device, or from the support device indirectly connected to the input / output device to the input / output device. It shows what is done.

The “connection ID” is a device number that identifies the input / output device when a command is transmitted from the support device indirectly connected to the input / output device to the input / output device.
“Command” indicates the type of command (reading, writing, changing, etc. of operation parameters), and “Data” indicates data accompanying the command (command operand). For example, in the case of writing or changing operation parameters, data to be written or data to be changed is set here.

  In FIG. 4, the command packet that is the result of the conversion of the request message includes “message control”, “processing status”, “transaction number”, “source I / O bus station number”, “command”, and “data”. Consists of each item.

  Among these, “processing status”, “command”, and “data” match those of the request message. Further, the “transmission source I / O bus station number” indicates the device number (station number) of the input / output device corresponding to the “connection ID”.

FIG. 5 is a sequence diagram showing a basic communication procedure in the present embodiment.
In FIG. 5, in (1), a request message is transmitted from the support apparatus 4 to the PLC 1 via the general-purpose network 6. Upon receiving this request message, the PLC 1 converts the request message into a command packet (first message) as shown in FIG. 4, and transmits the command packet to the input / output device in (2).

  In the input / output device that received the command packet, the first response is the result of the reception process such as “data cannot be interpreted”, “normally received”, “the input / output device itself is not operating normally”, etc. To the input / output device.

  This first response is received within the processing time of the input / output device from the time of transmission of the first message (that is, the time required for changing or reading out the operation parameter on the input / output device side) (3) Then, the PLC 1 transmits a read packet (second telegram) instructing to read and notify the processing result to the input / output device in (4). As the read packet, a fixed value indicating the read packet is predetermined between the PLC 1 and the input / output device.

  The input / output device that has received the read packet responds thereto. That is, the processing result is transmitted to the PLC 1 as a second response. The processing result is, for example, information indicating whether or not the writing or changing of the operation parameter is normally completed in the case of writing or changing the operation parameter, and the reading is normally completed in the case of reading the operation parameter. It is an operation parameter to be read out together with information indicating whether or not it has been performed.

  The PLC 1 that has received the second response in (5) generates a response message including information on the processing result, and transmits the response message to the support device 4 via the general-purpose network 6 in (6).

  As described above, according to the system configured by the PLC 1 and the input / output device of the present embodiment, instead of connecting the support device to the communication interface for the support device of the input / output device, the support device 4 is connected to the PLC 1. The support device 4 communicates a request to the input / output device via the PLC 1. As a result, when connecting the support device, the location of the input / output device (servo amplifier, inverter, etc.) that is hardly noticeable in the place where the control target device is installed is found, and it is freed from the trouble of cabling at that location. It is possible to reduce the load of connection work of the support device. Also, remote operation is possible according to the transmission distance of the general-purpose network 6 of the PLC 1, and hardware compatibility is maintained without increasing the hardware cost of the input / output device. Can be connected.

FIG. 6 is a flowchart of relay processing by the PLC 1 in the present embodiment.
In step S <b> 11 of FIG. 6, it is determined whether a request message for indirect connection is received from the support device 4. This determination is performed depending on whether the station number of the input / output device specified in the connection ID item of the request message shown in FIG. 4 is registered in the indirect connection target table shown in FIG. When it is determined that the connection ID of the request message received in step S11 is not registered in the indirect connection target table (when the determination result in step S11 is No), the reception waiting state in step S11 continues.

  When it is determined that the connection ID of the request message received in step S11 is registered in the indirect connection target table (when the determination result in step S11 is Yes), the request message is converted to a message conversion unit in step S12. 34 is converted into a command packet and stored in a command transmission buffer (not shown).

  In the subsequent step S13, the command packet (first electronic message) stored in the command transmission buffer is transmitted to the corresponding input / output device by the command packet transmission unit 36. Starting from the time when this command packet is transmitted, the ACK (first response) reception specified time and IO (input / output device) processing capacity specified time (the requested process is executed on the input / output device side) Counting of the time required) is started.

In step S14 following step S13, it is determined whether or not an ACK (first response) has been received within a specified time for receiving the ACK.
If it is determined in step S14 that ACK (first response) has not been received within the specified time for ACK reception (if the determination result in step S14 is No), an abnormal response process is performed in step S18, and a series of processes Exit.

  If it is determined in step S14 that an ACK (first response) has been received within the specified time for ACK reception (if the determination result in step S14 is Yes), the processing capability of the IO (input / output device) is determined in step S15. It is determined whether the specified time has elapsed.

  As long as the IO processing capacity regulation time has not elapsed (as long as the determination result of step S15 is No), the waiting state of step S15 continues. When the IO processing capacity regulation time has elapsed (when the determination result in step S15 is Yes), in step S16, the read packet transmitting unit 38 instructs to read and notify the processing result (second packet). Message) is transmitted to the input / output device. Starting from the time of transmission of this command packet, the ACK reception specified time and IO (input / output device) processing capacity specified time (required for executing the requested processing on the input / output device side) Time) starts counting.

In step S17, it is determined whether or not an ACK (second response) has been received within a specified time for receiving the ACK.
If it is determined in step S17 that ACK (second response) has not been received within the specified time for ACK reception (if the determination result in step S17 is No), an abnormal response process is performed in step S18, and a series of processes Exit.

  If it is determined in step S17 that ACK (second response) has been received within the specified time for ACK reception (if the determination result in step S17 is Yes), processing included in the second response in step S19 Data corresponding to the result is stored in a response buffer (not shown).

In step S20, data corresponding to the processing result stored in the response buffer is transmitted to the support device 4 by the response message transmission unit 35, and the series of processing ends.
FIG. 7 is a flowchart of data transmission / reception processing of the input / output device according to this embodiment. Note that. In this flowchart, it is assumed that the input / output device receives any of the configuration information collection packet, the command packet, and the read packet.

  In step S31 of FIG. 7, it is determined whether a packet has been received. As long as no packet is received (as long as the determination result in step S31 is No), this reception waiting state continues. When a packet is received (when the determination result of step S31 is Yes), it is determined in step S32 whether the received packet is a configuration information collection packet.

  If it is determined that the packet received in step S32 is a configuration information collection packet (if the determination result in step S32 is Yes), whether or not the input / output device supports indirect connection of the support device in step S33. A configuration information packet including such information is transmitted to the PLC 1 and a series of processes is terminated.

  If it is determined that the packet received in step S32 is not a configuration information collection packet (if the determination result in step S32 is No), it is determined in step S34 whether the received packet is a command packet.

  When it is determined that the packet received in step S34 is a command packet (when the determination result in step S34 is Yes), in step S35, an ACK (first response) is transmitted to the PLC 1 and the series of processing ends. To do.

  If it is determined that the packet received in step S34 is not a command packet (if the determination result in step S34 is No), it is determined in step S36 whether the received packet is a read packet.

  When it is determined that the packet received in step S36 is a read packet (when the determination result in step S36 is Yes), in step S37, an ACK with data (second response) as a processing result is transmitted to the PLC 1, A series of processing ends.

  Note that there is an upper limit on the amount of data that can be exchanged with the input / output device by one communication. When this upper limit is exceeded, the command packet, the read packet, and the second response must be divided into a plurality of times. In other words, when writing or changing operation parameters, the amount of operation parameters to be written exceeds the upper limit value, so the command packet is sent to the input / output device in multiple batches. Since the amount of the operation parameter to be read exceeds the upper limit value, the read packet and the second response are transmitted to the PLC 1 in a plurality of times.

  FIG. 8A is a sequence diagram illustrating an extended communication procedure (part 1) in the present embodiment. In the case where the amount of command packet data is large as in the case of writing operation parameters, the command packet is transmitted to the input / output device in multiple times (here, twice).

  In FIG. 8A, a request message is transmitted from the support apparatus 4 to the PLC 1 via the general-purpose network 6 in (1). The PLC 1 that has received the request message converts the request message into command packets (first message) (1/2) and (2/2) as shown in FIG. The command packet (1/2) is transmitted to the input / output device. That is, here, it is assumed that the data size shown in the item “data” in FIG. 4 exceeds the upper limit and the command packet is transmitted in two steps. Further, division information (K / N, 1 ≦ K ≦ N, where N is the number of divisions) for division transmission is included in each command packet.

  In the input / output device that has received the command packet (1/2), the result of reception processing such as “data cannot be interpreted”, “normally received”, “the input / output device itself is not operating normally”, etc. Is transmitted to the input / output device as a first response (1/2).

  When the first response (1/2) is received in (3) within the processing capacity time of the input / output device from the time of transmission of the first telegram (1/2), the PLC 1 subsequently receives a command packet ( 2/2) is transmitted to the input / output device at (4).

  In the input / output device that has received the command packet (2/2), the result of reception processing such as “data cannot be interpreted”, “normally received”, “the input / output device itself is not operating normally”, etc. Is transmitted to the input / output device as a first response (2/2).

  When the first response (2/2) is received in (5) within the processing capacity time of the input / output device from the time of transmission of the first telegram (2/2), the PLC 1 reads and notifies the processing result. In step (6), a read packet (second telegram) instructing to do so is transmitted to the input / output device.

The input / output device that has received the read packet responds thereto. That is, the processing result is transmitted to the PLC 1 as a second response.
The PLC 1 that received the second response within (7) within the processing capacity time of the input / output device from the time of transmission of the second message generates a response message including information on the processing result, and sends the response message to ( In step 8), the data is transmitted to the support device 4 via the general-purpose network 6.

  FIG. 8B is a sequence diagram illustrating an extended communication procedure (part 2) in the present embodiment. Here, a case is shown in which the read packet and the second response are transmitted to the PLC 1 in two steps.

  8B, in (1), a request message is transmitted from the support apparatus 4 to the PLC 1 via the general-purpose network 6. Upon receiving this request message, the PLC 1 converts the request message into a command packet (first message) as shown in FIG. 4, and transmits the command packet to the input / output device in (2).

  In the input / output device that received the command packet, the first response is the result of the reception process such as “data cannot be interpreted”, “normally received”, “the input / output device itself is not operating normally”, etc. To the input / output device.

  When the first response is received in (3) within the processing capacity time of the input / output device from the time of transmission of the first message, the PLC 1 instructs to read and notify the processing result (second packet). (1/2) is transmitted to the input / output device in (4). As the read packet, a fixed value is previously determined between the PLC 1 and the input / output device.

  The input / output device that has received the read packet (1/2) makes a response thereto. That is, the processing result is transmitted to the PLC 1 as a second response (1/2). Here, the processing result is, for example, information indicating whether or not the reading of the operation parameter has been normally completed, and the operation parameter to be read. In addition, division information (K / N, 1 ≦ K ≦ N, where N is the number of divisions) for division transmission is included in each second response.

  The PLC 1 that received the second response (1/2) in (5) within the processing capacity time of the input / output device after the transmission of the second message (1/2) is followed by the processing result (subsequent portion). Read packet (second telegram) (2/2) instructing to read and notify is sent to the input / output device in (6).

The input / output device that has received the read packet (2/2) makes a response thereto. That is, the processing result (subsequent portion) is transmitted to the PLC 1 as the second response (2/2).
The PLC 1 that received the second response (2/2) in (7) within the processing capacity time of the input / output device from the time of transmission of the second message (2/2) is the second message (1/2) Then, a response message including the processing result information collected by the second message (2/2) is generated, and the response message is transmitted to the support apparatus 4 via the general-purpose network 6 in (8).

  In the above description of FIG. 8B, for convenience, the read packet (1/2) (2/2) is used. However, these are actually the same fixed value, and there may be subsequent data from the division information. It is assumed that the read packet is continuously sent while it is known.

It is a figure which shows schematic structure of the operation parameter access system which concerns on one Embodiment of this invention. It is a figure which shows the detailed structure of the operation parameter access system of FIG. It is a flowchart of a collection process of configuration information. It is a figure which shows the data structure of an indirect connection object table. It is the figure which showed the command packet which is a request message and the conversion result of the request message. It is a sequence diagram which shows the basic communication procedure in this embodiment. It is a flowchart of the relay process by PLC in this embodiment. It is a flowchart of the data transmission / reception process of the input / output device in this embodiment. It is a sequence diagram which shows the extended communication procedure (the 1) in this embodiment. It is a sequence diagram which shows the extended communication procedure (the 2) in this embodiment. It is a figure which shows the conventional system configuration. It is a figure which shows the process at the time of the request message reception in the system of FIG.

Explanation of symbols

1, 51 PLC
2, 52 I / O device 3, 53 Dedicated network 4, 5, 54 Support device 6 General-purpose network 11 Communication type selection unit 12 Direct communication unit 13 Indirect communication unit 21 Configuration information management unit 22 Protocol conversion unit 23 Transceiver 24 System work memory 25 User data memory 26 User program memory 27, 42, 56 IO / bus interface unit 28 Internal bus 31 Configuration information collection unit 32 Configuration information registration unit 33 Request message reception unit 34 Message conversion unit 35 Response message transmission unit 36 Command packet transmission unit 37 First response receiver 38 Read packet transmitter 39 Second response receiver 41, 55 Dedicated support device data processor 43, 57 Transmission buffer 44, 58 Request message analyzer 45, 59 Response message transmitter 46 Received packet Analysis unit 47 Configuration information response unit 48 Command packet response unit 49 Read packet response unit

Claims (8)

In the programmable controller connected via the first communication means with the input / output device for controlling the control target device,
The programmable controller is further connected via a second communication means and a support device for setting operation parameters for the input / output device,
The programmable controller is
A first request transmission unit that converts a request command for requesting setting of the operation parameter from the support device into a first command in a format in which the first communication unit can communicate and transmits the command to the input / output device; ,
A second request transmission unit for transmitting a second command for obtaining a processing result of the input / output device for the first command;
When a processing response including the processing result in response to the second command is received from the input / output device, the processing response is converted into a format communicable by the second communication means and transmitted to the support device. A programmable controller comprising a processing result transmission unit. The programmable controller according to claim 1,
A programmable controller, further comprising: a configuration information collection unit that collects configuration information indicating whether or not the input / output device is compatible with a communication protocol of the first communication unit from the input / output device. The programmable controller according to claim 1,
The first request transmission unit divides the first command into a plurality of times when the data amount of the request command exceeds the upper limit of the data amount that the input / output device can receive at one time. And transmitting to the input / output device. In the input / output device that controls the control target device connected by the programmable controller and the communication means,
A first response transmission unit that transmits an acceptance response indicating acceptance of the first command to the programmable controller when receiving a first command that requests setting of an operation parameter from the programmable controller;
A response processing unit that performs processing according to the first command;
A second response transmission unit configured to transmit a processing response including the processing result to the programmable controller when a second command for requesting transmission of the processing result of the response processing unit is received from the programmable controller. An input / output device characterized by The input / output device according to claim 4,
The second response transmission unit divides the processing response into a plurality of times when the data amount of the processing response exceeds an upper limit value of the data amount that the input / output device can communicate at a time. An input / output device that transmits to the programmable controller. A programmable controller is connected to the input / output device for controlling the control target device via the first communication means, and also via the support device and the second communication means for setting operation parameters for the input / output device. Connected operating parameter access system,
The programmable controller is
A first request transmission unit that converts a request command for requesting the setting of the operation parameter from the support device into a first command in a format in which the first communication unit can communicate and transmits the first command to the input / output device; ,
A second request transmission unit for transmitting a second command for obtaining a processing result of the input / output device for the first command;
When a processing response including the processing result in response to the second command is received from the input / output device, the processing response is converted into a format communicable by the second communication means line and transmitted to the support device A processing result transmission unit
The input / output device is
A first response transmission unit that transmits an acceptance response indicating acceptance of the first command to the programmable controller when receiving a first command that requests operation parameter setting from the programmable controller;
A response processing unit that performs processing according to the first command;
A second response transmission unit configured to transmit a processing response including the processing result to the programmable controller when a second command requesting transmission of the processing result of the response processing unit is received from the programmable controller. Operating parameter access system characterized by. The parameter access system according to claim 6,
The first request transmission unit divides the first command into a plurality of times when the data amount of the request command exceeds the upper limit of the data amount that the input / output device can receive at one time. And transmitting to the input / output device. The parameter access system according to claim 6,
The second response transmission unit divides the processing response into a plurality of times when the data amount of the processing response exceeds an upper limit value of the data amount that the input / output device can communicate at a time. An operating parameter access system, wherein the operating parameter is transmitted to a programmable controller.