JPH0227839A - Communication management method - Google Patents

Abstract

PURPOSE:To attain the building of a bus system offering highly efficient system operation with low cost by reading out type information of its communication sequence from each terminal equipment by a system controller and varying the communication sequence from each terminal equipment based thereupon. CONSTITUTION:The system controller 11 reads sets of communication sequence type information 15, 16 provided in terminal equipments 12, 13 from them via a communication controller 8 and a communication bus 4 and discriminates which terminal equipment is operated by which kind of communication sequences by referencing a sequence table 14. In the case of transmission of a control message to each terminal equipment from the system controller 11, the control message is sent by using the communication sequence suitable for the terminal equipment being the sent destination. Thus, one system controller sends the control message to plural terminal equipments and the optimum system constitution with expansion in response to the applications of the system and its cost is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for managing communication sequences between terminal devices in a data communication network.

BACKGROUND OF THE INVENTION FIG. 2 shows a communication network configuration and a connection state of terminal devices in a bus system. The system controller 5, the terminal device 6, and the terminal device 7 are the communication control device 1 and the communication control device 2.
, are connected to each other by a communication bus 4 via a communication control device 3. When the system controller 6 and each terminal device mutually transmit information via the communication control device and the communication bus 4, the communication sequence flow when the communication sequence between the system controller 6 and each terminal device is different is shown below. It is shown in FIGS. 3 and 4. In both FIGS. 3 and 4, a case will be considered in which a control message is transmitted from the system controller 6 to the terminal device 6 and the terminal device 7 via the communication control device and the communication bus.

In FIG. 3, first, as control 1, a control message a is transmitted from the system controller 6 to the terminal device 6. The terminal device 6 that receives this message performs the control specified by the message. Furthermore, the system controller 6 determines that the previously transmitted control message a is the terminal device 6.
In order to confirm whether or not processing and control have been performed correctly, the data readout a is transmitted to the terminal device 6, and the terminal device 6 confirms the control by returning the control result to the system controller 6. Next, as control 2, the terminal device 7 is controlled and confirmed by the control message b and data read b using the same procedure. FIG. 4 shows a flow according to a communication sequence different from the communication sequence in FIG. 3. Here, first, as control 1, a control message C is transmitted from the system controller 6 to the terminal device 6. Upon receiving this message, the terminal device 6 performs the control specified by the message, confirms by itself that the control has been performed correctly, and returns the control result as an operation response C to the system controller 6. Thereby, the system controller 6 confirms whether the previous control message was correctly processed in the terminal device. Similarly, control message d from the system controller 6 is sent to the terminal device 7 as control 2.
A communication sequence is used in which the terminal device 7 returns an operation response d in response to the request. Such a communication sequence is uniquely set for each system, and which communication sequence to use is selected depending on the nature of system operation. Third
When the communication sequence shown in the figure is used, there is less content to be processed on the terminal equipment side than in the case of Fig. 4, and the cost of the terminal equipment itself can be reduced. On the other hand, when the communication sequence shown in FIG. 4 is used, there are more contents to be processed on the terminal equipment side than in the case of FIG. 3, and the cost of the terminal equipment itself becomes higher. However, in terms of expandability and reliability as a communication system, the method using the communication sequence shown in FIG. 4 is superior.

Problems to be Solved by the Invention Considering the efficiency and cost of the system, it would be convenient if a system could be constructed by mixing a plurality of communication sequences and making use of the strengths of each.

However, the communication sequences shown in Figures 3 and 4 cannot be used together in the same system, so only one communication sequence operates in one system, and when various terminal devices are connected, Therefore, the communication sequence that operates cannot be changed.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention has a system controller that reads, from each terminal device connected to a communication bus, the type information of the communication sequence in which the terminal device operates during the initial setup of the system. However, based on this, the system controller changes the communication sequence for each terminal device.

Effects of the Invention With the above-described configuration, the present invention can construct a bus system that can operate the system at low cost and with high efficiency.

Embodiment FIG. 6 shows the configuration of the system controller 11 in an embodiment of the present invention.
The terminal device 12 and the terminal device 13 are each a communication control device 8
, a communication control device 9, and a communication control device 10, and are interconnected by a communication bus 4. System controller 11
has a sequence tape 1v14 inside, which is information indicating the procedures of a plurality of communication sequences. Furthermore, each terminal device has communication sequence type information, which is information indicating which communication sequence the terminal device operates with. System controller 11 and terminal equipment 12
FIG. 1 shows a sequence flow of the communication method according to the present invention for information transmission between the terminal device 13 and the terminal device 13. First, at the time of initial setting of the system, the system controller 11 reads communication sequence type information contained in each terminal device from each terminal device via the communication control device and the communication bus 4. That is, the communication sequence type information 16 in the terminal device 12 and the communication sequence type information 16 in the terminal device 13 are read as registered information message 17 and registered information read message 18.
Start reading carefully. Communication sequence type information is similarly read from all other terminal devices connected to the communication bus, and the system controller 11 has a sequence table 14 that indicates which terminal devices operate in which type of communication sequence.
Make a decision by referring to As a result, after the initial setup of the system, when transmitting control messages from the system controller 11 to each terminal device, multiple control messages can be transmitted in a communication sequence suitable for the terminal device to which the system is being transmitted. . That is, when transmitting a control message from the system controller 11 to the terminal device 12 as control 1, a communication sequence of control message e transmission and data reading, which is a communication sequence suitable for the terminal device 12, is adopted to transmit the control message. transmission. Next, as control 2, from the system controller 11 to the terminal device 1
When transmitting a control message to the terminal device 13, the control message is transmitted using a communication sequence suitable for the terminal device 13, which is the control message amount transmission and the operation response f from the terminal device.

Effects of the Invention As described above, according to the present invention, it is possible to transmit control messages to a plurality of terminal devices by one system controller in a communication network in which a plurality of terminal devices that operate according to different communication sequences are connected. This makes it possible to construct an optimal system with scalability depending on the system, system usage, and cost, which is extremely effective in practice.

[Brief explanation of the drawing]

Fig. 1 is a sequence diagram of one embodiment of the communication sequence in the communication management system of the present invention, Fig. 2 is a configuration diagram of a conventional communication network, and Figs. 3 and 4 are the conventional system shown in Fig. 2. FIG. 5 is a diagram showing a communication sequence in the configuration, and is a configuration diagram of terminal equipment in a communication network in which the communication management method of the present invention is adopted. Name of agent: Patent attorney Shigetaka Awano and 1 other person 1 Figure 2 Figure 2

Claims (1)

[Claims] In a bus system in which terminal devices each having a communication control device are connected via a communication bus, when a plurality of terminal devices that function in different communication sequences are connected to the communication bus, the terminal devices themselves function. A system controller having communication sequence type information and connected to the bus system reads the communication sequence type information from the plurality of terminal devices at the time of system initialization, and the system controller and the terminal devices communicate. When transmitting information via a bus, a control sequence suitable for the terminal device of the communication partner is selected from a plurality of control sequence tables held by the system controller based on the type of the communication sequence read from the terminal device. A communication management method characterized by changing the control sequence depending on the terminal device of the communication partner.