JPS62169257A - Terminal control system - Google Patents

Abstract

PURPOSE:To eliminate the response delay time due to polling selection by performing the communication between at least one work station and a station controller through a shared memory. CONSTITUTION:At least one work station 4 connects processors 2 and 6 through a shared memory 13. Since processors 2 and 6 communicate with each other by the shared memory 13, communication control mechanisms are made unnecessary and the time overhead due to communication control is eliminated. Plural work stations 4 are connected to a station controller 12.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF APPLICATION OF THE INVENTION The present invention relates to systems consisting of station-based controller workstations, and more particularly to systems in which one or more workstations are staged.

This relates to a terminal control method that communicates with a remote controller via a shared memory.

[Background of the invention]

A method of defining operations and exchanging data between processors via a shared memory is well known as a local processor method. Furthermore, Japanese Patent Application Laid-open No. 54-6743 discloses a system in which processing devices are connected via a memory circuit that can be written to and read from. It is generally used to control a processor in an input/output control mechanism or as a multi-system configuration means, and there is no disclosure of memory coupling of one or more of a plurality of workstations for communication control.

A conventional control method will be explained using FIGS. 4 and 2. FIG. 4 shows a system comprising a stage controller 1 and a plurality of workstations 4, which is generally used as a control method for large-scale systems. The station controller 1 is composed of a processing device 2 and a communication control mechanism 3. Of course, a file device such as a disk or magnetic tape, and a printing mechanism such as a line printer are connected to the station controller 1. The communication control mechanism 3 is generally connected to a plurality of workstations 4 via a single wire 9 such as a coaxial cable or a twisted pair wire in a multi-drop manner using a serial interface. As a communication control method, HDLC means or a polling/selection method is used to achieve a transfer rate of several 10KBPs to several MBPS. The communication control mechanism in the 4-piece workstation station controller becomes the primary station, and the communication system A4 structure 5, which is the secondary station, and the input/output control mechanism 7 that controls the keyboard and display 8, and these are unified and controlled. It is composed of a processor 6. The features of the system shown in Fig. 4 are that the station Φ controller 1
All work without connecting the keyboard/display directly.

All the software that controls Stage 4 can be made common. Although this method is suitable for constructing a large-scale system, since a station controller is required when constructing a small-scale system, the amount of hardware becomes a cost overhead. Furthermore, since communication with the workstation is always performed via a serial interface, there is an overhead for response, resulting in poor response performance.

On the other hand, FIG. 5 shows a system configuration consisting of a master stage 10 and a work station 4. As shown in FIG. Compared to FIG. 4, the processor 2 of the master stage controls the keyboard display 8 via its control mechanism 11, and the first configuration has the advantage of being realized with less hardware. The input/output mechanism that controls the keyboard display is separate from the master station mechanism 11 and the workstation mechanism 7, and the software that controls them is also two systems, which has the disadvantage of complicating the system construction. be.

[Purpose of the invention]

An object of the present invention is to provide a communication control mechanism for controlling a plurality of work stages, in which at least one workstation and a station controller communicate via a shared memory, thereby reducing response delay due to polling conflict selection. In addition to improving performance by eliminating
To provide a terminal control method that eliminates the need for a communication control mechanism on the side of a work stage.

[Summary of the invention]

The present invention provides a system comprising a plurality of workstations having independent processors, each of which has a shared memory that can be read and written by each processor of at least one or more workstages and the processor of a station controller. ,
This system is characterized in that a station controller adds an opportunity for communication via a shared memory to a communication control program for controlling workstations.

[Embodiments of the invention]

FIG. 1 shows one embodiment of the present invention. In this configuration, at least one workstation 4 is connected to the processors via the shared memory 13 in the system configuration shown in FIG.

The feature of this system is that the processor 2 and the processor 6 communicate through a shared memory, thereby eliminating the need for a communication control mechanism, reducing the amount of equipment, and eliminating time overhead due to communication control.

FIG. 2 explains the role of the shared memory 13 in more detail. A shared memory is constituted by a status Φ area 14, a write data buffer area 15, and a read data buffer area 16, in which the processors 2 and 6 communicate with each other the completion of startup.

Normally, the software is designed so that the processor 2 periodically reads the status area 14 and checks its contents, thereby knowing whether there is a request to send or receive data from the processor information 6. . On the other hand, when processor 6 wants to send or receive data to processor 2, it writes a promise code indicating a read/write request in a specific bit of the status area. The means by which processor 2 and processor 6 use shared memory is well known as a technique for constructing a multi-system, such as test-and-set instructions, and is not mentioned here because it is not directly necessary for disclosing this patent. .

FIG. 3 is a flowchart illustrating the flow of the above-described processing. All workstations other than workstations that communicate using shared memory are controlled using the normal communication control method, and the software can be constructed by simply modifying a portion of this driver without affecting other structures. .

[Brief explanation of drawings]

Fig. 1 is a block diagram of an embodiment of the present invention, Fig. 2 is a block diagram of a shared memory, Fig. 6 is a flow chart of processing of the present invention, Fig. 4 is a block diagram of a station controller system, and Fig. 5 is a block diagram of an embodiment of the present invention. is a block diagram of the master stage system. 1... Stage controller, 2... Processor, 3... Communication control 1! I structure, 4... Work station, 5... Secondary station communication control mechanism, 8... Keyboard/display, 9... Interface cable, 10... Master station. Daimari △'ff

Claims (1)

[Claims] 1. In a system consisting of a plurality of workstations each having a station controller and an independent processor, the station controller is equipped with a shared memory that can be read and written by each processor of at least one or more workstations and the processor of the station controller. A terminal control method characterized by adding a means of communicating via shared memory to a communication control program that controls a workstation.