JPH09331368A - Communication procedure automatic selection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply build up a gateway by selecting and using automatically a device making communication with an object device and a protocol in matching with the object device. SOLUTION: A host LAN where nodes a-n being nodes 1 are connected to a transmission line 2 and a subordinate LAN where nodes A-N being nodes 5 are connected to a transmission line 4 are connected to a gateway 3. The gateway 3 connects the host LAN and the subordinate LAN in which transmission signals are sent by different protocols and the protocol is converted in matching with the inter-system protocol. A plurality of protocol software sets are mounted on the gateway 3 and signals are sent sequentially to the nodes 5 according to a plurality of protocol softwares and the protocol available of communication with the nodes 5 is selected. Thus, a device in communication with an object node and the protocol in matching with the node are selected and used automatically.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for automatically selecting a communication procedure, and more particularly to a method for automatically selecting a communication procedure characterized by the selection of the communication procedure when devices having different protocols are used for communication. Is.

[0002]

2. Description of the Related Art When exchanging information between various information devices, it often becomes a problem whether communication procedures (protocols) between the devices are the same. For example, in a process control device for controlling a plant, a node such as an operator station, which is a monitoring device, is connected to a network such as a LAN, while a sequencer or the like is connected to a different LAN to form a network.

Then, the above two networks are connected via a gateway to construct a system. At this time, communication between the network on the monitoring device side and the network on the sequencer side via the gateway is realized by protocol conversion in the gateway.

Even in the case of such a process control device, it is very often necessary to adjust the protocol between the information devices. For example, there is a device called an engineering tool as a device that loads programs and data to control devices such as sequencers and controllers, and other information devices, reads the data in the memory of the information devices, and performs various checks and services. .

The engineering tool is connected to various information equipments manufactured by various makers and is accessed. Therefore, at this time, the engineering tool needs to communicate using the protocol of the device to be accessed.

Here, as an example of information exchange between information devices, a case of a process control device will be described in more detail. The gateway connects systems that are transmitting by different protocols and converts the protocols according to the protocols of the mutual systems. Hereinafter, the LAN to which the monitoring device (operator station) is connected, that is, the monitoring device side network is referred to as an upper LAN, and the LAN to which the sequencer or the like is connected, that is, the sequencer side network is referred to as a lower LAN.

In many cases, the gateway is the upper LAN
Are directly connected to each other so that data can be exchanged. On the other hand, the lower LAN is subjected to protocol conversion for communication.

Conventionally, as shown in FIG. 12, when designing the entire system, protocol software suitable for the transmission protocol of the lower LAN is appropriately selected and installed in the gateway.

FIG. 12 is a diagram showing a state in which protocol software is stored inside a conventional gateway.
As shown in the figure, the only protocol software 71 is set in the gateway. The operation in this case will be described below.

Here, it is assumed that the monitoring device has configuration information of devices connected to the upper LAN and the lower LAN, including the gateway, in the monitoring device. First, for example, when the monitoring device tries to display information on a node such as a sequencer connected to a lower LAN, the lower LA
Data needs to be collected from nodes on N.

However, the upper L to which the monitoring device is connected
If the transmission protocol of the lower LAN to which the AN and the sequencer are connected is different, it is impossible for the monitoring device to directly collect the information of the sequencer.

Therefore, a gateway between the upper LAN and the lower LAN allows both protocols to communicate with each other.
It is converted into N protocol and transmitted. Specifically, the data read request text from the monitoring device to the sequencer of the lower LAN is transmitted to the gateway,
The gateway converts this into a data read request text that can be understood by the sequencer of the lower LAN, and then the lower LAN
Transmit to the above sequencer.

The sequencer receiving the request text,
The requested data is transmitted to the gateway in a response text according to the lower LAN protocol. The gateway converts it into a response text of the upper LAN and sends it to the monitoring device on the upper LAN that is the request source.

As a result of this series of conversions, the monitoring device can collect the data of the sequencer. The data collection has been described above, but data writing can also be realized by performing exactly the same protocol conversion.

[0015]

As can be seen from the above, the gateway connected to the upper LAN needs to exchange the protocol software each time the protocol to be converted changes to operate. .

Therefore, the conventional process control device is
There were the following problems regarding data transmission between the upper LAN and the lower LAN. (1) When the protocol to be converted in the gateway changes, it is necessary to replace and operate the protocol software each time, which complicates system construction. (2) If protocol software is installed by mistake, it cannot function as a gateway and cannot operate as a system. (3) It is necessary to install conversion software in the gateway while always being aware of the protocol of the conversion target device (sequencer). (4) Unless the protocol of the conversion target device (sequencer) is well understood, software construction of the gateway is impossible, and the skill of an engineer is required to construct the system. (5) When the model or manufacturer of the sequencer is changed, the protocol may be changed, and the gateway software needs to be changed.

Further, not only in the case of the process control device,
Even when a device such as an engineering tool is connected to a target device such as a sequencer to input data, if the protocols of the two devices are different, data cannot be input or read from the engineering tool. Therefore, it was necessary to input protocol software to the engineering tool and set it according to the protocol of the target device.

As described above, when the communication is performed by connecting the self and the target device, or when the self and the target device are connected and data is input to the target device or data is read from the target device, the self and the target device are connected. It was always necessary to keep in mind the protocol between devices.

That is, it is necessary to set the protocol software suitable for the target device to itself, and when the protocol software becomes incompatible due to a change in the situation or a change in the target device, communication or input is made to the target device. Between the device and the target device, the above (1) to (5)
There was a similar problem to.

The present invention has been made in consideration of such circumstances, and a first object thereof is to automatically select a protocol compatible between a device communicating with a target device and the target device. It is to provide a communication procedure automatic selection method to be used.

A second purpose is to automatically select a communication protocol for automatically selecting and using a compatible protocol between a device that executes data input and data read to the target device and the target device. To provide a method.

[0022]

In order to solve the above-mentioned problems, the invention according to claim 1 is such that, when communication is carried out between devices having different protocols, a plurality of devices are previously prepared for one of the devices to be communicated. It is equipped with various types of protocols, and at the time of initial operation of one device, a signal is sent from the one device,
This is a communication procedure automatic selection method in which a protocol suitable for communication is selected from a plurality of types of protocols based on a response to the transmitted signal and used.

Further, the invention according to claim 2 is a case where one device having a protocol performs one-sided access such as data input or data read to the other device, and Equipped with multiple types of protocols in advance, one of the devices sends a signal at the time of initial operation, and based on the response from the other device to the sent signal, access is selected from among the multiple types of protocols. It is a method of automatically selecting a communication protocol to be used by selecting a protocol to be used.

Further, the invention according to claim 3 is a case where one device having a certain protocol communicates with one of a plurality of other devices using any one of a plurality of types of protocols. In this case, one device is equipped with a plurality of types of protocols in advance, and at the time of initial operation of one device, a signal is sent from the one device to each of the other devices, and one of the devices is sent based on the response to the sent signal. A communication procedure in which a protocol compatible with each communication between a device and each other device is selected from a plurality of types of pre-installed protocols, and one device uses a protocol suitable for the communication partner. This is an automatic selection method. (Operation) Therefore, first, in the communication procedure automatic selection method of the invention according to claim 1, when communication is performed between devices having different protocols, one of the devices performing the communication has a plurality of protocols in advance. Is installed.

Here, at the time of the initial operation of one device, a signal is sent from the one device, and a protocol suitable for communication is selected from a plurality of types of protocols based on the response to the sent signal.

At the time of the above communication, the selected protocol is used. Further, in the communication procedure automatic selection method of the invention according to claim 2, when one device each having a protocol performs one-way access such as data input or data read to the other device, One type of device is preloaded with a plurality of types of protocols.

Here, at the time of the initial operation of one device, a signal is sent from the one device, and a protocol suitable for access is selected from among a plurality of types of protocols based on the response from the other device to the sent signal. To be selected.

Then, at the time of the above access, the selected protocol is used. Furthermore, in the communication procedure automatic selection method of the invention corresponding to claim 3, one device having a certain protocol and one of the plurality of other devices using any one of the plurality of types of protocols are used. In the case of performing communication, one device is preloaded with a plurality of types of protocols.

Here, during the initial operation of one device, a signal is sent from the one device to the other device,
Based on the response to the transmitted signal, a protocol suitable for each communication between one device and the other device is selected from a plurality of types of pre-installed protocols. Then, at the time of the communication, one device uses a protocol suitable for the communication partner.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. (First Embodiment of the Invention) FIG. 1 is a block diagram showing a configuration example of a process control apparatus to which a communication procedure automatic selection method according to a first embodiment of the present invention is applied.

As shown in the figure, in this process control device, an upper LAN in which nodes a to n which are nodes 1 are connected to a transmission line 2 and nodes A to N which are nodes 5 are connected to a transmission line 4. The connected lower LAN is the gateway 3
It is configured to be connected to.

In the upper LAN, the node 1 is composed of, for example, a monitoring device, and has configuration information of devices connected to the upper LAN and the lower LAN including a gateway, and collects information of each node 5 of the lower LAN, for example. And monitor it.

On the other hand, in the lower LAN, the node 5
It is composed of a sequencer, a controller, etc., and controls, for example, plant processes. The monitoring device, which is the node 1 on the upper LAN, makes a data collection request (request text) to the sequencer, which is the node 5 on the lower LAN.
Is transmitted to the lower LAN via the gateway.

On the other hand, the response text from the sequencer which is the node 5 on the lower LAN is protocol-converted by the gateway 3 and transmitted to the upper LAN. Gateway 3
Is to connect an upper LAN and a lower LAN that are transmitting by different protocols, and perform protocol conversion according to the protocol of the mutual system (LAN).

The same protocol is used in the upper LAN, and the same protocol is used in the lower LAN. Here, the gateway 3 itself is an upper LAN
And operates with the protocol of the upper LAN. Therefore, the gateway 3 operates, for example, in response to an access from the monitoring device, but is a device that takes the initiative in accessing the node 5 of the lower LAN. That is, the gateway 3 between the upper LAN and the lower LAN serves as a master station on the transmission protocol for the lower LAN.

For this reason, the gateway 3 is a subordinate LA.
It has the configuration information of the device connected to N. The communication procedure automatic selection method according to the present embodiment is to automatically determine the lower LAN protocol when the gateway 3 is started up in the system having the above-described configuration and select a suitable protocol software.

For this reason, a plurality of protocol software is stored in the gateway 3 as shown in FIG. FIG. 2 is a diagram showing a situation in which protocol conversion software is stored in the storage unit of the gateway according to the present embodiment.

As shown in the figure, the storage unit 6 of the gateway 3 is provided with a protocol software storage memory 7. The protocol software storage memory 7 has a plurality of protocol software X, Y ,. . . Z is stored. These protocol software X, Y ,. . . Z corresponds to various sequencers connected to the lower LAN, and is created in accordance with a known protocol. For example, protocol software X is for a sequencer manufactured by X company, protocol software Y is for a sequencer manufactured by Y company ,. . .
And so on.

Therefore, even if any sequencer of any manufacturer is connected to the lower LAN, the corresponding protocol conversion software exists in the protocol software storage memory 7.

The gateway 3 selects the protocol software suitable for the lower LAN from the memory 7 for storing the protocol software in accordance with a predetermined operation in the initial operation at startup. This operation will be described with reference to FIG.

FIG. 3 is a flow chart showing the processing of the communication procedure automatic selection method of this embodiment. The initial operation is executed immediately after the gateway is turned on or immediately after the initialization operation and before the original operation.

At this time, the following operation is performed in order to determine the protocol suitable for the node on the connected lower LAN. In addition, the following 1. ~ 4. ST1 shown in parentheses
To ST6 correspond to each step ST in FIG.

1. Select and execute in order from the protocol software X installed in the gateway (ST1,
ST4), a text for confirming the other party (for example, a return test text) is transmitted to node 5 (for example, node A) (ST2).

2. When a normal response is returned according to the protocol software executed from node A, for example, the protocol defined in protocol software X (ST3, ST5), the partner protocol corresponds to protocol software X. (ST)
5) After that, the original operation of the gateway 3 is to use the protocol software X (ST6), and shifts to the steady state.

3. If the response from node A times out due to no response (ST3), or if a response with unknown meaning (response that cannot be interpreted by software X) is returned (ST5), the protocol of node A is the protocol. It is determined that the software X is not supported (ST5).

4. The above 3. If so, the following protocol software Y is selected and executed to execute the above 1. (ST4, ST2), 2. Or 3. Make the same judgment as.

This operation 1. ~ 4. That is, in the flowchart of FIG. 3, steps ST1 to ST6 are repeated by the number of stored software. In this way, the gateway 3 is only connected to the lower LAN and automatically selects and sets the compatible protocol software. Therefore, communication is performed between the gateway 3 and the node 5 by the protocol used for each node 5.

If the conversion software cannot be determined even after executing all the protocol conversion software X to Z installed in the gateway 3, the fact is displayed on the gateway 3 and the monitoring device 1 to warn. To do.

By the above operation, the connection between the upper LAN and the lower LAN via the gateway 3 is automatically made only by the plug-in operation, and the gateway 3 shifts to the steady operation shown in FIG.

FIG. 4 is a flow chart showing an example of steady operation of the gateway using the communication procedure automatic selection method of the present embodiment. When a request text from the upper LAN or a response text from the lower LAN is input to the gateway 3 (S
At T11, the gateway 3 converts the protocol into a lower LAN or an upper LAN to be transmitted (ST1).
2).

At this time, the protocol conversion is performed by the above-mentioned automatically set protocol software. Then, the protocol-converted text is the lower L
Transmitted to AN or upper LAN (ST1
3).

As described above, in the communication procedure automatic selection method according to the embodiment of the present invention, a plurality of protocol software is installed in the gateway 3, and at the time of its initial operation, transmission is sequentially performed to the node 5 according to the plurality of protocol software. Since the protocol that can communicate with the node 5 is selected, it is possible to automatically select and use a compatible protocol between the device communicating with the target node and the node.

Therefore, in the conventional gateway, complicated work such as designing a system and selecting a program is performed by considering the protocol on the lower LAN which is the other party.
Since the protocol is automatically determined, it is possible to construct a system including a gateway without being aware of the lower LAN protocol.

As a result, it is possible to easily construct the gateway which seems to be the most complicated in constructing the system.
In particular, it is useful for a system that collects and writes data from LANs having different protocols via a gateway. (Second Embodiment of the Invention) FIG. 5 is a block diagram showing a configuration example of a process control apparatus to which a communication procedure automatic selection method according to a second embodiment of the present invention is applied, and is the same as FIG. Are denoted by the same reference numerals and description thereof is omitted, and only different portions will be described here.

The process control device shown in FIG.
It is composed of N and lower LANs and a gateway 11 connecting them. Here, the upper LAN has the same configuration as that of the first embodiment.

On the other hand, in the lower LAN, nodes # 1 to #N, which are N nodes 12, are connected to the transmission line 4, and each of these nodes # 1 to #N uses the same protocol. It does not always correspond, but it is a free combination.

For example, node # 1 is a sequencer manufactured by X company and corresponds to protocol software X, node # 2 is a sequencer manufactured by Z company and corresponds to protocol software Z, and so on.

Communication is performed between the upper LAN and the lower LAN as in the case of the first embodiment, and the gateway 11
At the time of steady operation, the upper LAN and the lower LAN that are transmitting by different protocols are connected, and the protocol conversion is performed according to the protocol of the mutual system (LAN).

Here, as in the first embodiment, the gateway 11 belongs to the upper LAN and becomes the master station in the transmission protocol for the lower LAN. Therefore, the gateway 11 has the configuration information of the devices connected to the lower LAN.

The communication procedure automatic selection method of this embodiment is
In the system having the above configuration, the protocol of each node 12 of the lower LAN is automatically determined when the gateway 11 is started up, and the protocol software suitable for each node 12 can be selected at the time of communication.

Therefore, as shown in FIG. 6, the information necessary for that purpose is stored in the storage unit of the gateway 11. FIG. 6 is a diagram showing the inside of the storage unit of the gateway according to the present embodiment.

As shown in the figure, the storage section 6 of the gateway 11 is provided with a memory 7 for storing protocol software and a lower LAN information section 13. As in the first embodiment, a plurality of protocol software X, Y ,. . . Z
Is stored.

On the other hand, in the lower LAN information section 13, the lower L
Various information about the AN is stored, and at least an information table 14 and a number information unit 15 in which information on the number of lower LAN connections is stored are provided.

The information table 14 stores protocol type information corresponding to each node 12. When the gateway 11 performs the protocol conversion for transmitting the text to the node 12 having the lower LAN or for responding the text from the node 12, the information table 14 indicates the type information of the corresponding protocol software.
Take out from. Then, according to the type information, the corresponding protocol software stored in the protocol software storage memory 7 is selected.

In the initial operation at the time of startup, the gateway 11 selects the protocol software corresponding to each node 12 according to a predetermined operation, and stores the corresponding type information in the information table 14. This operation will be described with reference to FIG.

FIG. 7 is a flow chart showing the processing of the communication procedure automatic selection method of the present embodiment. The initial operation is executed immediately after the gateway is turned on or immediately after the initialization operation and before the original operation.

First, in step ST21, i = 1
Is set to In this embodiment, the number of nodes is N and indicates the first node # 1. Next, the first protocol software stored in the protocol software storage memory 7, for example software X, is selected (ST22).

Next, using the selected protocol software, the text for confirming the other party (for example, the return test text) is sent to the node 12 (here, node # 1) corresponding to the currently set value of i. It is transmitted (ST23).

If there is no response (ST24), the next protocol software is selected (ST26), and step S
Return to T23. Even if there is a response (ST24), it is not a correct response according to the protocol (S24).
T25), the next protocol software is selected (S
T26) and returns to step ST23.

On the other hand, if there is a response (ST24),
If the response is a correct response according to the protocol (ST25), the protocol software selected this time is determined to be suitable for the i-th node 12 (ST27), and the corresponding information is the information table. 14
(ST28).

Next, if the set value of i is N (ST29), it is determined that the association of the protocol types is completed up to the node #N, and the initial operation is finished, while the value of i is N. If not (ST29), the value of i is incremented by 1 (ST30) and the process returns to step ST22.

In this way, the gateway 11 determines the compatible protocol software for all the nodes 12 and stores the corresponding relationship, and shifts to the steady state shown in FIG.

FIG. 8 is a flow chart showing an example of steady operation of the gateway using the communication procedure automatic selection method of the present embodiment. When a request text from the upper LAN or a response text from the lower LAN is input to the gateway 3 (S
T31), the gateway 3 determines which node 12 in the lower LAN is the destination or source of the text.
It is determined whether (# 1, # 2, ... #N) is supported (ST32).

Next, the type information of the protocol software corresponding to the node 12 determined in step ST32 is retrieved from the information table, and the protocol conversion is performed by the corresponding protocol software stored in the protocol software storage memory 7 ( ST33 # 1
~ ST33 # N).

Then, the protocol-converted text is sent to the lower LAN or the upper LAN (ST34). As described above, in the communication procedure automatic selection method according to the embodiment of the present invention, a plurality of protocol software is installed in the gateway 11, and at the time of its initial operation, transmission is sequentially performed to the node 12 according to the plurality of protocol software, Since the protocol that can communicate with each node 12 is selected and the protocol software suitable for the communication partner is used at the time of communication, even if the target nodes use different protocols, the communication with the target node is performed. A compatible protocol can be automatically selected and used between the device and the node.

Therefore, in the conventional gateway, the device using the same protocol of the same manufacturer is connected in the lower LAN which is the other party, but according to the present invention, the gateway automatically uses the protocol of each communication target node of the lower LAN. It is possible to connect any kind of equipment of any manufacturer of the lower LAN and to construct a system including a gateway with a high degree of freedom without being conscious of the protocol because the protocol software is selected and the protocol software is selected. (Third Embodiment of the Invention) FIG. 9 is a block diagram showing a connection example of an engineering tool to which a communication procedure automatic selection method according to a third embodiment of the present invention is applied.

The engineering tool 21 is connected to, for example, a device such as a sequencer 22, loads a program into the sequencer 22, and reads the memory contents in the sequencer 22.

At this time, the engineering tool 21
Must use protocol software corresponding to the connected device (sequencer 22) and perform input to the sequencer 22 using a necessary protocol.

However, the connected sequencer 22
Different devices use different protocols depending on the device manufacturer and device type, and different protocol software is required for each device.

Therefore, the engineering tool 21 of the present embodiment includes the memory 7 for storing the memory protocol saltware shown in FIG. 2 and performs the same initial operation as the gateway 3 in the first embodiment shown in FIG. Is configured.

As a result, the engineering tool 21
Investigates which protocol the sequencer 22 supports in its initial operation, determines and sets the corresponding protocol software.

Hereinafter, in the steady operation, the engineering tool 21 uses the selected protocol software to input data to the sequencer 22 and read data from the sequencer 22.

Further, the connection relationship between the engineering tool 21 and the equipment (sequencer 22) does not have to be limited to the one-to-one connection as shown in FIG. FIG. 10 is a block diagram showing another connection example of the engineering tool to which the communication procedure automatic selection method according to the present embodiment is applied.

In this case, the plurality of nodes 31 are connected to the transmission line 32.
The engineering tool 33 is connected to one node 31 of the LAN connected to the. Here, the initial operation / steady operation of the engineering tool 33 is similar to the above case.

As described above, the communication procedure automatic selection method according to the embodiment of the present invention is performed by the engineering tool 2
1, 33 are provided with a plurality of protocol software, and at the initial operation, the protocol is transmitted to the sequencer 22 or the node 31 in accordance with the plurality of protocol software to select an accessible protocol. On the other hand, it is possible to automatically select and use a compatible protocol between a device that executes data input, data reading, etc. and the device to be accessed.

Therefore, it is not necessary to input and set the protocol software matching the protocol of the access target device into the engineering tool one by one, and the processing by the engineering tool or the like can be simply and easily performed. (Fourth Embodiment of the Invention) FIG. 11 is a block diagram showing a connection example of an engineering tool to which a communication procedure automatic selection method according to a fourth embodiment of the present invention is applied.

Also in this embodiment, the case where the engineering tool 21 is connected to another device to access the other device will be described. The engineering tool 43 according to the present embodiment has a plurality of nodes 41 shown in FIG.
Is connected to a LAN that is connected to a transmission line 42, and any one of the nodes 41 is accessed through the transmission line 42.

Here, each node 41 does not always use the same protocol, and the engineering tool 43 includes the memory 7 for storing the memory protocol saltware shown in FIG. 6, and the second embodiment shown in FIG. It is configured to perform the same initial operation as the gateway 3 in the embodiment.

When the same connection as in FIG. 11 is made and each node 41 uses the same protocol, the engineering tool 43 includes the memory 7 for storing the memory protocol software shown in FIG. , Fig. 3
Is configured to perform an initial operation similar to that of the gateway 3 in the first embodiment shown in FIG.

With the above configuration, the engineering tool 43 investigates which protocol the node 41 corresponds to in the initial operation according to the flow shown in FIG. 3 or 7, and determines and sets the corresponding protocol software. To do.

Then, in the steady operation, the engineering tool 43 uses the selected protocol software to input data to any of the nodes 41 and read data from the node 41.

As described above, the communication procedure automatic selection method according to the embodiment of the present invention is performed by the engineering tool 4
3 is equipped with a plurality of protocol software, and at the time of its initial operation, transmission is sequentially performed to the node 41 in accordance with the plurality of protocol software to select an accessible protocol. Obtainable. Further, in this case, since the engineering tool 43 is connected to the transmission path 42 of the LAN, it is possible to access a plurality of nodes 41 with one connection.

Further, in the case of this embodiment, the node 41
Even if the protocol used is different, access is possible and the same effect can be obtained as in the case of the second embodiment.

In the first and second embodiments, an example in which the present invention is applied to a process control device will be described.
In the fourth embodiment, the example in which the present invention is applied to an engineering tool has been described, but the present invention is not limited to these examples, and protocol conversion is performed to communicate or input with a connected target device. The present invention can be applied to various devices as long as they are devices for reading and the like. Furthermore, the present invention is not limited to the above-mentioned respective embodiments, and can be variously modified without departing from the gist thereof.

[0095]

As described in detail above, according to the present invention, there is provided a device for communicating with a target device and an automatic communication procedure selecting method for automatically selecting and using a protocol compatible with the target device. can do.

Further, according to the present invention, a communication procedure automatic selection for automatically selecting and using a compatible protocol between a device that executes data input and data reading with respect to the target device and the target device. A method can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration example of a process control device to which a communication procedure automatic selection method according to a first embodiment of the present invention is applied.

FIG. 2 is a diagram showing a situation in which protocol conversion software is stored in a storage unit of the gateway according to the first embodiment.

FIG. 3 is a flowchart showing processing of a communication procedure automatic selection method according to the same embodiment.

FIG. 4 is a flowchart showing an example of steady operation of a gateway using the communication procedure automatic selection method according to the embodiment.

FIG. 5 is a block diagram showing a configuration example of a process control device to which a communication procedure automatic selection method according to a second embodiment of the present invention is applied.

FIG. 6 is a diagram showing the inside of a storage unit of the gateway according to the same embodiment.

FIG. 7 is a flowchart showing the processing of the communication procedure automatic selection method according to the embodiment.

FIG. 8 is a flowchart showing an example of steady operation of a gateway using the communication procedure automatic selection method according to the embodiment.

FIG. 9 is a block diagram showing a connection example of an engineering tool to which the communication procedure automatic selection method according to the third embodiment of the invention is applied.

FIG. 10 is a block diagram showing another connection example of the engineering tool to which the communication procedure automatic selection method according to the embodiment is applied.

FIG. 11 is a block diagram showing a connection example of an engineering tool to which the communication procedure automatic selection method according to the fourth embodiment of the present invention is applied.

FIG. 12 is a diagram showing a state in which protocol software is stored inside a conventional gateway.

[Explanation of symbols]

 1, 5, 12, 31, 41 ... Node 2, 4, 32, 42 ... Transmission line 3, 11 ... Gateway 7 ... Protocol software storage memory 21, 33, 43 ... Engineering tool

Claims (3)

[Claims] 1. When communication is performed between devices having different protocols, one of the devices that performs the communication is preliminarily loaded with a plurality of types of protocols, and the one of the devices is initially operated. A method for automatically selecting a communication procedure, characterized in that a protocol suitable for the communication is selected from the plurality of types of protocols and used based on a response to the transmitted signal. 2. When performing one-sided access such as data input or data read from one device having a protocol to the other device, the one device is provided with a plurality of types of protocols in advance. During the initial operation of the one device, a signal is transmitted from the one device, and a protocol suitable for the access is selected from the plurality of types of protocols based on a response from the other device to the transmitted signal. A method for automatically selecting a communication procedure characterized by being used. 3. One device having a protocol,
In the case of performing communication with any one of a plurality of other devices using any one of a plurality of types of protocols, the one device is preloaded with a plurality of types of protocols, At the time of initial operation, a signal is sent from the one device to each of the other devices, and a protocol adapted to each communication between the one device and each of the other devices is preliminarily installed based on a response to the sent signal. A method for automatically selecting a communication procedure, characterized in that each of the plurality of types of protocol is selected, and the one of the devices uses the compatible protocol according to a communication partner.