JPS6120452A - Data exchange congestion control system - Google Patents

Abstract

PURPOSE:To cause no revocation of a data by placing a congestion control device between a communication control unit and a central control unit, generating a notice of generation or release of a congestion instantaneously to the central control unit through the congestion control unit from the communication control unit in accordance with necessity, and executing a control of a data transmission. CONSTITUTION:When the generation of a congestion occurs, a switching signal (generation of congestion) of a specified pattern signal is sent to a congestion control unit 5 through a branching device 4 from a communication control unit 1, a notice of the generation of a congestion is transmitted instantaneously to a central control unit 2, and the central control unit 2 stops the transmission of a data. Subsequently, when the congestion is gone in the communication control unit 1, a switching signal (release of congestion) of a specified pattern signal is sent to the congestion control unit 5 through the branching device 4 from the communication control unit 1, a notice of the release of a congestion is transmitted to the central control unit 2, and the central control unit 2 starts to transmit a data to the communication control unit 1 again.

Description

[Detailed description of the invention] This relates to the electrical connection control method used in this study.

Conventional Technology Conventionally, in data exchange processing, when there is a lack of memory capacity for received data in a communication control device, that is, congestion occurs, electrical connections are made between the communication control device and a central control device using the same bus used for data transfer. Notification of occurrence or cancellation was given. At this time, the overlap occurrence notification from the communication control device is
Since the data is placed after the data that has already been ranked for transmission by the communication control device, the central control device is not notified instantly but is notified a little later.

Therefore, there is a drawback that data held in the communication control device and data received from the central control device are discarded while the congestion occurrence notification is delayed.

Problems to be Solved by the Invention The present invention solves the above-mentioned drawbacks, that is, the occurrence of electrical connection is not immediately notified to the central control unit, and data is discarded within the communication control unit. This is a book that provides a data exchange overlap control method.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a separate route between the communication control device and the central control device via a branch device and a congestion control device in addition to the bus connection. , when an electric ring is generated or canceled in the communication control device, a specific pattern signal from the communication control device is sent to the congestion control device via the branching device, and the congestion control device is connected to the central control device. A configuration is adopted in which a congestion occurrence (or cancellation) notification is issued to the central control device to control data transmission from the communication control device.

Operation Since the present invention is configured as described above, a congestion occurrence notification is transmitted to the communication control device, thereby preventing data from being discarded due to electrical connection in the communication control device.

Example Next, embodiments of the present invention will be described with reference to the drawings.

Referring to FIG. 1, which shows a block diagram of an embodiment of the present invention, the data exchange congestion control method originally developed is based on a main connection between a communication control device 1 and a central control device 2 via a bus 3. A separate route is provided which passes through a branching device 4 and a congestion control device 5.

The operation will be described with reference to FIG. 1 and FIG. 2, which shows an example of the sequence of generation and release of the axle.

First, the communication control unit ft, 1 receives data from the central control unit 2 via the bus 3. If a width light occurrence occurs at this time, a switching signal (overlap occurrence) of a specific pattern signal is sent from the communication control device 1 to the overlap control device 5 via the branching device 4. When the shaft control device 5 receives the switching signal, it instantly transmits an electrical connection occurrence notification to the central control device 2, and the central control device 2 stops transmitting data.

Next, when the communication control device 1 loses electrical contact, a switching signal (congestion release) of a specific pattern signal is sent from the communication control device 1 to the @gorge fitlJ control device 5 via the branching device 4, and the axle wheel control device At the same time as receiving this switching signal, the central controller 5 transmits a width light release notification to the central controller 2, and the central controller 2 again starts transmitting data to the communication controller bml.

In this way, the switching signal (light width generation or congestion release) can be sent through a route other than the data transfer bus route, so there is no delay in notification.

As described in detail, according to the present invention, the axle wheel control device is placed between the communication control device and the central control device, and the communication control device instantaneously transmits information via the ridge control device as needed. Since it is possible to issue a notification of the occurrence or release of electrical connection to the central control unit and control data transmission, a high degree of reliability can be obtained and data can be prevented from being discarded.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a diagram illustrating an example of a sequence of congestion occurrence and release in the present invention. 1...Communication control device, 2...Central control device, 3...Bus, 4...Branch device,
5...Radio control device, 6...Line. U is also positive pressure.”

Claims (1)

[Claims] In a data processing system in which a communication control device that performs data exchange processing and a central control device are connected via a bus,
A separate route passing through a branching device and a congestion control device is provided between the communication control device and the central control device, and the communication control device side receives data from the line or from the central control device. When congestion occurs due to lack of memory capacity during the process, and when the congestion is resolved,
A specific pattern signal is transmitted from the communication control device to the congestion control device via the branching device, and the congestion control device controls data transmission from the central control device to the communication control device. data exchange congestion control method.