JPH04289944A - Communication establishment control system - Google Patents

Abstract

PURPOSE:To control the polling interval in accordance with the constitution of the system and the performance of a terminal equipment side. CONSTITUTION:In the establishment control system of a communication processing of various terminal equipment groups, and between the terminal. equipments which are placed as subordinates through a transmission line for sharing those terminal equipments and take charge of the communication processing to each terminal equipment and a host computer, it is constituted so that in a terminal controller 100, a terminal equipment management information table 21 in which management information corresponding to a state of each terminal of the subordinate is posted is provided, and also, a communication controller 10 for sending out a communication processing establishment request frame to each terminal in accordance with this management information is provided, and an operation corresponding to a state of each terminal can be executed.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to a communication establishment control system, and in particular, the present invention relates to a communication establishment control method, and in particular, the present invention relates to a communication establishment control system, and in particular, a group of various terminal devices, and a host computer that connects the terminal devices to a host computer by placing the terminal devices under control via a shared transmission path. The present invention relates to a control method for establishing communication processing between terminal control devices that control data communication processing with a terminal control device.

0002

[Prior Art] In a system in which a terminal control device and various terminal devices (display devices, printer devices, workstations, etc.) that are subordinate to the terminal control device share a transmission path between devices such as a LAN transmission path. , when a terminal control device attempts to establish communication processing with individual terminal devices under its control, the terminal control device side must grasp the status of each terminal device under its control (power-off/operating/stopped, etc.). There is a need to.

[0003] For this reason, each terminal device is periodically polled (sending frames such as requests for establishing communication processing),
The status of each terminal device is grasped by the response to polling.

FIG. 3 shows the overall configuration of a system in which a terminal control device and a plurality of terminal devices are connected by a single common transmission line, and each terminal device is placed under the control of the terminal control device. In the figure, 30 is a terminal control device, and has a plurality of terminal devices 31 to 35 under its control. In particular, the terminal device 3
4 and 35 indicate terminal devices connected via the branch 33. 36 is a host computer, and each of the terminal devices 31 to 35 is connected to this host computer under the control of the terminal control device 30.

[0005] In such a system, the terminal control device 30 controls the status of the slave terminal device (power off/in operation/
We conduct regular polling to check for any outages, etc. The polling method is a method in which all terminals are polled at predetermined fixed time intervals.

[0006] This allows the terminal control device 30 to grasp the status of the terminal devices 31 to 35 under the control of the terminal control device 30.

[0007]

[Problem to be solved by the invention] As stated above,
In the conventional example, polling is performed at fixed time intervals for all terminal devices under control, including, for example, unused terminal devices.

However, in recent systems, terminal devices are not only connected to a host computer to perform communication processing with the host computer, but also are often used standalone to perform various types of processing. There is.

[0009] By the way, as described above, polling for a terminal device that is operating standalone is not only useless in terms of operation, but also polling for a terminal device that is operating stand-alone is not only useful in terms of operation, but also in a system in which a single transmission line is shared by multiple terminal devices. This has the problem of increasing the load on the line.

[0010] Furthermore, the response time to polling varies depending on the length of the transmission path, the configuration of the system such as via branches (routers), and the performance of the equipment (response to polling), so polling is performed at regular intervals. In this case, before the response from the terminal reaches the terminal controller,
There may be cases where new polling is performed. In this case, the terminal control device naturally performs wasteful polling, resulting in a problem that the system cannot be operated efficiently.

The present invention has been made in view of the above points, and an object thereof is to provide a communication establishment control method that can be operated efficiently in accordance with the system configuration and operating conditions.

0012

[Means for Solving the Problems] In the present invention, it is possible to control whether or not polling (communication processing establishment request frame) is sent out and the polling interval for each terminal device under the terminal control device, and the polling interval can be controlled depending on the system configuration and operating conditions. This enables efficient operation.

FIG. 1 is a block diagram for explaining the principle of the present invention. Note that FIG. 1 mainly shows parts related to the polling operation of the terminal control device. In the figure, 100 indicates a terminal control device, which includes a communication control device 10, a terminal device management information table 21 provided in a terminal device management information memory, and a hard disk 22 in which the above-mentioned management table and the like are stored. It is configured. Further, the plurality of terminal devices 27 to 29 to be controlled are connected to this terminal control device in a manner that they share one line.

Management information for each terminal set by the terminal control device setup setting items shown in table 200 is entered in the management information table 21. These setting items include the presence or absence of an establishment request for each terminal, and the time required for each terminal to respond when polling is performed for each terminal (hereinafter simply referred to as polling interval).

The communication control device 10 is a terminal control device 100.
It is in charge of overall control, and at that time, it refers to the management information table and performs control according to the management data written in the management information table.

[0016]

[Operation] When the terminal control device 100 is activated, the communication control device 10 first sends the management information stored in the hard disk to the terminal device management information memory, and expands the management information into a management information table. Next, polling will be performed for each terminal, but when sending a polling signal to each terminal, the management information table 21 is first referred to, and each terminal is polled according to the management information for each terminal written in the management information table. Poll the terminal.

For example, according to the management information shown in FIG.
Polling is started for the first terminal at a polling interval of 40 ms. That is, 40ms after sending the polling signal.
If there is no response during this time, the first terminal is polled again. This polling interval is an optimal value determined based on the transmission path, terminal performance, etc., and thereby performs polling with the highest efficiency.

[0018] Furthermore, polling is not performed for the second terminal according to the management information. This makes it possible to perform appropriate polling according to the system configuration and operating state.

[0019]

Embodiment FIG. 2 shows an embodiment of the present invention. In FIG. 2, the same parts as in FIG. 1 are given the same numbers, and detailed explanations of these parts will be omitted. Also,
The description will be made assuming that the terminal device information table 21 contains the same management information as shown in FIG. 1.

In FIG. 2, the communication control unit 10 includes a management information reading unit 11 for reading a terminal device management information table, a polling signal generation unit 12, a transmitting unit 13, and a communication control unit that performs operations other than polling. Terminal status monitoring section 14, response signal decoding section 15 for decoding the response signal from the terminal, receiving section 16, transmission time acquisition section 17 for capturing the time at which the polling signal was transmitted, polling from the transmission time and polling interval a calculation unit 18 that calculates the response time for the polling, a time-over detection unit 19 that detects that the scheduled time for receiving the polling response signal has elapsed from the transmission of the polling signal, and the input/output control unit 101
Contains. In addition, there is also an area 24 for recording the response time of each terminal in the memory as a work area for detecting time-overs, and a clock 2 for measuring transmission times, etc.
There are 3.

The operation of this embodiment will be explained with reference to FIG. The process of first importing the management information for each terminal in the hard disk 22 into the terminal device management information table 21 in the memory is as explained in conjunction with the principle diagram.
This is initiated, for example, by a command from the keyboard of the first terminal 27. At this time, it is preferable that the table 200 described in FIG. 1 be displayed on the display device of the terminal 27, and any items in the items can be changed.

When the development of the management information into the management information table 21 is completed, this table 21 is transferred to the management information reading section 11.
will be read by the terminal and start polling each terminal. Among the read management information, the polling interval is transmitted to the calculation unit 18. To start polling the first terminal 27, the polling signal generator 1
2 gives ID information and the like to the terminal 27, and then transmits it to the terminal via the transmitter 13 and I/D 101 via a common transmission path.

When the polling signal is sent from the transmitter 13, the sending time acquisition unit 1 detects that the polling signal has been sent.
7 can be conveyed. The transmission time acquisition section 17 acquires the time from the clock 23 based on this signal, and further sends this time to the calculation section 18. Since the calculation unit 18 is informed of the polling interval of the terminal 27 read from the management information reading unit 11, it adds this polling interval to the transmission time and calculates the response time (scheduled) from the first terminal 27. ) is written in the memory 24.

The terminal 27 receives this polling signal by reading the ID signal at the beginning of the signal. Then, it immediately creates a response signal and sends it back to the terminal control device 10 side. Response signal is I/O10
1. Sent to the response signal decoder 15 via the receiver 16,
Here, it is decoded to determine which terminal the response signal is from, etc., and the contents are transmitted to the terminal status monitoring section 14.

At the same time, the response signal decoder 15 notifies the memory 24 that there has been a response signal from a specific terminal, in this case the first terminal 27. The response time of each terminal is recorded in the memory 24, and this response time is determined in consideration of the state of the transmission path, the capability of the terminal, etc. Therefore, in normal operation, the response signal is within the response time of the first terminal 27 written in the memory 24. When this signal is transmitted to the memory 24, the memory 24 resets the response time of the first terminal in the memory.

[0026] If the polling signal is not transmitted to the first terminal 27 for some reason, the polling signal will be transmitted again, but according to the present invention, the next polling signal is transmitted for each terminal. This is done after a predetermined polling interval has elapsed.

This operation will be explained below. The time-over detection unit 19 reads the response time of each terminal written in the memory 24, compares this with the time from the clock 23, and constantly monitors terminals that do not respond even after the scheduled time. . For example, in the case of the first terminal 27, if a response signal is not received even after 40 ms have elapsed since the polling signal was transmitted, the time-over detection unit 19 detects this and
The polling signal generation unit 12 is notified as a retry signal that there is no response from the first terminal 27. After receiving this retry signal, the polling signal generator 12 transmits the polling signal to the first terminal 27 again.

[0028]

[Effects of the Invention] As described above, according to the present invention, the polling interval is determined in advance according to the status of each terminal, and polling is retried for each terminal according to this, so that the polling interval is determined uniformly. More efficient polling can be achieved than in the conventional example in which polling is performed again at time intervals. In addition, for terminals that are used in a standalone state, polling can be omitted by registering this as management information in the management information table in advance. can reduce the burden on

[Brief explanation of the drawing]

FIG. 1 is a principle block diagram for explaining the principle of a communication establishment control method of the present invention.

FIG. 2 is a functional block diagram for explaining the configuration and operation of an embodiment of the present invention.

FIG. 3 is a diagram showing an overview of an entire system including a terminal control device and a terminal device for explaining a conventional example.

[Explanation of symbols]

10 Communication control device 21 Terminal device management information table 22 Hard disk 27, 28, 29 Terminal device 100 Terminal control device

Claims (2)

[Claims] Claim 1: Communication processing between various terminal devices and a terminal control device that is placed under the control of these terminal devices via a shared transmission path and that controls communication processing between each terminal device and a host computer. In the establishment control method, a terminal device management information table (21) is provided in the terminal control device (100) in which management information corresponding to the status of each subordinate terminal is entered, and information is sent to each terminal according to this management information. A communication control device (10) for sending a communication processing establishment request frame.
), and enables operation according to the status of each terminal. 2. The communication establishment control system according to claim 1, wherein the management information includes whether or not the communication processing establishment request frame can be sent and an interval between sending the request frames.