JPH0722288B2 - Communication control device for local area network - Google Patents

Description

The present invention relates to a communication control device for a local area network. In particular, the present invention relates to a local area network communication control device in which a plurality of different types of programmable control devices are connected via a communication path via one or more nodes.

〔Overview〕

The present invention relates to a communication control device of a local area network in which programmable control devices having a plurality of different control procedures are coupled to each other, capable of coping with different types of control procedures, each programmable control device communicating with each other, and communication activation. By including a control procedure that activates communication at the required timing, it is possible to build a local area network that combines programmable controllers of different models.

[Conventional technology]

At present, in many production sites, factory automation that automates the production system is required, so various control devices located on the production site, machine tools, or a network that connects host computers that control the whole is constructed. Then, it is considered to form a local area network which is a control system for communicating between the control devices or between the host computer and the control device. In particular, a programmable controller introduced to control equipment or machines is provided with a communication control function to construct a network system.

For example, Japanese Patent Publication No. 57-28988 shows an example of constructing a local area network between information processing devices.

However, the communication control function provided in the programmable control device is different for each manufacturer, and the communication control procedure is different.

[Problems to be Solved by the Invention]

Therefore, when attempting to build a network system by connecting programmable controllers to each other or a host computer of a higher level, the programmable controllers have different communication control functions, so different manufacturers and different models of programmable controllers It has been difficult to build a network in which devices are connected.

Also, even if you try to build a system that communicates with already installed programmable control devices or with a host computer at a production site where various programmable control devices have been introduced, the communication function will originally differ depending on the model. , It was difficult to build a system to communicate with each other.

Furthermore, many of these different programmable control devices are equipped with RS232C etc. as a versatile control interface, but there was no one equipped with a communication control function assuming communication control with other models. It was difficult to build a system that combines the different types of programmable controllers that were already introduced.

INDUSTRIAL APPLICABILITY The present invention is capable of connecting different types of programmable control devices having different control procedures and a host computer to communicate with each other, and is installed also in different types of programmable control devices that have already been introduced. It is an object of the present invention to provide a communication control device for a local area network capable of constructing.

[Means for solving problems]

The present invention provides a local area network in which a plurality of programmable control devices are coupled by a communication path via one or more nodes, and in a communication control device arranged at the node, each of the plurality of programmable control devices is provided. The set control procedure is two or more different types, and the communication control apparatus can correspond to the different type control procedure set in the programmable control apparatus connected to the lower order of the node. Includes a control procedure for mutual communication with each other, and a control procedure for monitoring the operation of each programmable control device and starting communication at a timing when communication start is required.

[Action]

The communication control device of the present invention selects different types of control procedures, monitors the operation of each programmable control device, and activates communication of the programmable control device so that programmable control devices of different control procedure models communicate. It can be performed.

Further, the communication control device packaged and attached to the programmable control device functions as a node to control communication.

〔Example〕

 Examples of the present invention will be described below.

The feature of this communication control device is that the communication control procedure corresponding to each model of each company is installed inside the local area network, and the programmable control device without the communication activation right is constantly monitored. It has a control procedure for activating communication at a timing when communication activation is required, and can be installed in the programmable control device as one package.

First of all, the mutual communication speed in this local area network is 64 bytes / packet transfer rate instead of general 1 Kbyte / packet because data exchange between programmable control devices is a small amount of data and requires high speed. ing.

In the communication control device, the register numbers and coil numbers in the programmable control device of each company are stored as relative address addresses so that they can correspond to the models of different manufacturers, and the internal memory of each local area network is used as a data transfer medium. Because it is used, you can use it without being aware of different models. As a result, in the communication control device, the simple shared program enables communication between programmable controllers of different manufacturers and different models.

In addition, in this local area network, each node processes the received data from each node other than the reception of the programmable control device by the command, and the node is of the communication active type that does not perform it before, and each node loads the user program. Otherwise, it will not operate, so maintenance of user programs and maintenance of operation data can be easily performed.

The control procedure of this communication control device performs communication processing by performing the following.

First, the memory of the communication control unit is cleared, the target programmable control unit manufacturer for each channel in the local area network is designated, and the transfer between the shared digital input / output and the internal memory is performed. If the host computer is connected to the local area network address # 0, the status of each local area network is grasped by a command command from the host computer. This is performed by the following four processes. Turn on / off the host computer and the terminal of the local area network address # 0. Start and stop a simple shared program for each local area network. Transfer the simple shared program of each local area network to the host computer and output the list. The simple shared program is transferred from the host computer to each local area network, and the bit image or coil of the simple shared program is distinguished from the data image or register of the simple shared program. Perform error handling for each command. By this processing, the operation of each programmable controller is monitored. Execute each simple shared program set in each local area network. This is to convert the relative address in the simple shared program into the absolute address for the target programmable controller by transmitting between the internal memory of each local area network and storing the data from the target programmable controller of each local area network to the internal memory of the own station. , Transmitting between internal memories of each local area network, and storing data in the internal memory of the local area network that constantly monitors the operating state of the target programmable control device of each local area network. By this processing, the communication control procedure for each programmable control device connected to the node of the local area network can be executed.

The table below shows the memory compatibility of this embodiment of the communication control device.

Memory addresses 0000 to 1FFF are assigned to the system program for the local area network, and addresses 2000 to 3F
FF is assigned to the user system program, and the address
4000 to 5FFF are assigned to the buffer for the local area network system program, and addresses 7000 to 7FFF
Are assigned to the system for RS232C interface communication, addresses 8000 to 9FFF are assigned to the network reception buffer of the communication control unit, addresses A000 to BFFF are assigned to the network transmission buffer of the communication control unit, and addresses C000 to C7FF are assigned. It is assigned to the simple shared program transmitted from the host computer. However,
Address 3 if the simple shared program is in ROM
Use COO ~ 3FFF. Addresses C800 to CFFF are assigned to the absolute address translation buffer for each company of the relative address that the simple shared program decodes. Addresses D000 to D7FF are assigned to the buffer for data received from the target programmable controller. Addresses D800 to DFFF are assigned to the buffer for direct transmission to the host computer.

The communication control device of this embodiment is installed in each node of the local area network and the host computer, but is mounted in one package and can be installed in the housing of each programmable control device connected to the lower order of each node. Since the communication control device mounted in this housing can function as if it were a node of the local area network for communication, the programmable control devices can be directly connected to each other to form a network.

Next, an example of constructing a local area network by using a communication control device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 2 shows an example in which one programmable control device and a host computer are connected to one node of the local area network. Node 1 of the local area network, host computer 5, and programmable control device 6 are connected via an RS232C interface. To do. The node 1 constantly monitors the programmable controller 6 and stores the operation information of the programmable controller 6 in the internal memory of the node 1. Therefore, the host computer 5 having the communication activation right and the node 1 of the local area network
If the communication control is performed in, the communication control between the programmable controller 6 and the host computer 5 without the activation right can be performed.

Figure 3 shows one node 1 in a local area network
An example in which the programmable controller 6 of company A and the programmable controller 7 of company B are connected to a programmable controller of a different manufacturer via an RS232C interface is shown in FIG. In this connection, the node 1 monitors the operation of each programmable control device, and based on the operation information command of each programmable control device, writes to and reads from the target programmable control device via the internal memory of the node 1 to perform programming. Communication control of the control device can be performed.

The part shown by the dotted line is the case where the communication control device mounted in one package is mounted on the programmable control device 6 of A company, and the communication control device mounted on the programmable control device 6 of A company is the node 1. Because it works
The part indicated by the dotted line is in the programmable controller 6 of company A, and the programmable controller 6 of company A and the programmable controller 7 of company B are connected to each other to form a network.

Figure 4 shows one node 1 in a local area network
Is an example in which four programmable control devices 6, 7, and 8 of different manufacturers A, B, and C are respectively connected via an RS232C standard interface. Also in this case
Similarly to the local area network in the figure, the node 1 monitors the operation of each programmable control device, and based on the operation information command of each programmable control device, writes to and reads from the target programmable control device via the internal memory of the node 1. By doing so, communication control is performed.

Fig. 5 shows A for node 1 of the local area network.
The programmable controller 6 of the same company is connected via the RS232C interface, the programmable controller 7 and 8 of the company B and C are connected to the node 2 via the RS232C interface, and the programmable controller of the company A is connected to the node 3. 6 is connected via the RS232C interface, node 4
Is an example in which a relay board 9 is connected for data-in and data-out. The communication path between the nodes 1 to 4 is composed of a bus. In this local area network, it is possible to control communication between programmable controllers of different manufacturers and different models and data-in / data-out signals from the relay board.

FIG. 1 shows an example in which a local area network is constructed by incorporating a communication control function unique to each manufacturer inside the network. Host computer 5 is RS on node 1
Are connected via a 232C interface, also, Company A programmable control device 6 _-1 6 _-3 is connected to, each other A's programmable control device communicates with a company A corresponds that the communication control function. Programmable control devices 7 _{-1 to} 7 _{-n of} company B are connected to the node 2 through the RS232C interface, and programmable control devices 7 _{-1 to} 7 _-n communicate with each other by the communication control function compatible with company B. it can. Also, the programmable controller 8 of Company C is RS23
Connected via 2C interface. Further, the programmable controller of Company A is connected to the node 3 via RS232C. The communication path between the nodes 1 to 3 is composed of a bus. In this local area network, programmable controllers that are spatially separated can be combined, and a flexible network of programmable controllers can be constructed.

〔The invention's effect〕

As described above, the present invention makes it possible to construct a network which is a flexible production system in which programmable controllers of different models manufactured by different manufacturers having different control procedures and other controllers are combined, and the programmable controllers of different models already introduced are constructed. It became possible to connect a control device and build a network.

Further, since the communication control device of the present invention can be installed in the programmable control device as one package, there is an effect that a programmable control device having the communication control device built therein can be connected to build a network with different types of programmable control devices. .

[Brief description of drawings]

FIG. 1 is an example in which a network is constructed by the communication device of the embodiment. 2 to 5 are examples in which a network is constructed by the apparatus of the embodiment. 1 to 4 ... Nodes, 5 ... Host computer, 6-8 ... Programmable control device (PC), 9 ... Relay board.

Claims (5)

[Claims] 1. A communication control device in which a local area network is constructed in which a plurality of programmable control devices are connected via a communication path via one or more nodes, and the local control is arranged at the node. There are two or more different types of control procedures set in, and the communication control device can correspond to different types of control procedures set in the programmable control device connected to the lower level of the node,
A local area characterized by including a control procedure for each programmable control device to communicate with each other and a control procedure for monitoring the operation of each programmable control device and activating communication at the timing when communication activation is required. Network communication controller. 2. The communication control device includes a buffer memory,
The communication control device for a local area network according to claim (1), wherein the communication data is temporarily stored in the buffer memory in a translated form. 3. The communication control device according to claim 1, wherein the communication control device is mounted in a package with a shoe and can be mounted in the housing of one programmable control device. Local area network communication controller. 4. The communication control device for a local area network according to claim 1, wherein the number of nodes is one and the communication path is an RS232C interface. 5. The method according to claim 1, wherein there are a plurality of nodes, an RS232C interface is included in a communication path connected from the nodes to a lower level, and a communication path connecting the nodes to each other is a bus. Local area network communication controller.