JPS6388984A - Data transmission system - Google Patents

Abstract

PURPOSE:To shorten time until starting operation following the parameter by receiving the parameter anew from a center unit when the parameter is not stored in a terminal equipment. CONSTITUTION:Received signals from a center unit are inputted to a receiving control circuit 2 through a receiving interface 1. The receiving control circuit 2 discriminates received signals, and when the signals are parameter information, the parameter is stored in a memory circuit 3. In the case where received signals are a command to collect data such as charging information etc., information is given to a transmission controlling circuit 4 to the effect that the signals are a command to collect data. When the parameter is stored in the memory circuit 3, the transmission control circuit 4 transmits necessary data to the center unit through a transmission interface 5 responding to the command to collect data. When the parameter is not stored in the memory circuit 3, a parameter vanishing signal is transmitted to the center unit through the transmission interface 5 responding to the command to collect data.

Description

TECHNICAL FIELD The present invention relates to a data transmission system, and more particularly to a data transmission system in a two-way CATV communication system that transmits data between a center device and a terminal device.

Prior Art In a two-way CATV communication system that transmits data between a center device and a plurality of terminals, the center device transmits various parameters necessary for operation to each terminal device, and then transmits various parameters to each terminal device. A data collection command is sent to collect billing information, etc.

Examples of the parameters include fee information indicating whether the transmitted program is paid or free, contract information indicating whether the program can be viewed or not.

Each terminal device operates to transmit various data such as billing information to the center device in response to the data collection command.

In the center device, in view of the fact that the terminal devices may not store the above-mentioned parameters, as a countermeasure, the center device periodically transmits the necessary parameters to each terminal device.

In such conventional data transmission systems, the center equipment periodically sends the necessary parameters to each terminal device, so if the terminal device does not store the parameters, a new one is sent from the center device. However, there is a drawback in that it takes time depending on the parameter sending cycle of the center device from the time the parameters are received to the time an operation based on the parameters is started. Another disadvantage is that this time is not constant.

OBJECTS OF THE INVENTION An object of the present invention is to shorten the time it takes for a terminal device to receive new parameters from a center device and start an operation based on the parameters when the terminal device does not remember the parameters necessary for its operation. The purpose of the present invention is to provide a data transmission method that enables

Structure of the Invention According to the present invention, there is provided a data transmission method in a bidirectional CATV communication system that performs data transmission between a center device and terminal and terminal devices, and in the center device, each terminal device After sending parameters necessary for each operation to each terminal device, a data collection command is sent to each terminal device, and the terminal device stores the parameters in response to the data collection command. If the presence is detected and the parameter is not stored, a parameter loss signal is sent to the center device, and in response to reception of the parameter loss signal, the center device resends the necessary parameter to the corresponding terminal device. A data transmission system is obtained which is characterized by the following.

1 凰3 Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 is a block diagram of a terminal device applied to an embodiment of the present invention. This terminal device has a receiving interface 1,
A reception control circuit 2, a storage circuit 3, a transmission control circuit 4,
It has a transmission interface 5.

In this configuration, a reception signal received from the center device (see FIG. 2) is input to the reception control circuit 2 via the reception interface 1. The reception control circuit 2 identifies the received signal and, if it is a parameter notification, causes the storage circuit 3 to store the parameter. Furthermore, if the received signal is a command to collect data such as billing information, it notifies the transmission control circuit 4 that it is a data collection command. If the parameters are stored in the storage circuit 3, the transmission control circuit 4 transmits the necessary data to the center device via the transmission interface 5 in response to the data collection command.

If the parameter is not stored in the storage circuit 3, a parameter loss signal is transmitted to the center device via the transmission interface 5 in response to the data collection command.

FIG. 2 is a block diagram of a center device applied to an embodiment of the present invention, which includes a transmission control circuit 6, a transmission interface 7, a storage circuit 8, a reception control circuit 9, and a reception interface 10.

In this configuration, the transmission control circuit 6 transmits parameters or data collection commands to each terminal device via the transmission interface 7. When the parameters are stored, the terminal device transmits the data to the center device in response to the data collection command, as described above, and when the parameters are not stored, it sends the parameter loss signal in response to the data collection command. Send to center device. This parameter disappearance signal is input to the reception control circuit 9 via the reception interface 10, and the reception control circuit 9 causes the storage circuit 8 to store the collected data in the case of data reception.

On the other hand, if the received signal is a parameter-vanishing signal,
A notification to that effect is sent to the transmission control circuit 6.

In response to the notification of the parameter disappearance signal, the transmission control circuit 6 retransmits the parameters necessary for the operation of the terminal device via the transmission interface 7 to the terminal device.

FIG. 3 is a block diagram of a bidirectional CATV communication system to which the present invention is applied, in which bidirectional communication is performed between the center device M1 and a plurality of terminal devices 81 to 3N. A procedure showing the operation of the embodiment of the present invention in such a case is shown in FIG.

In this way, the center device transmits the data collection command to each terminal device after transmitting the parameters necessary for its operation to each terminal device, and when the terminal device has stored the parameters, it responds to the data collection command. In response, data is sent to the center device.

If the parameter is not stored, a parameter loss signal is sent to the center device in response to the data collection command, and the center device responds to the parameter loss signal and sends the parameter necessary for the operation to the terminal device. will be resent. Therefore, even if the terminal device does not store the parameters, it is possible to shorten the time it takes to receive the parameters anew from the center device and to start an operation based on the parameters.

Effects of the Invention As described above, according to the present invention, when the terminal device does not store the parameters, it is possible to shorten the time it takes to receive the parameters again from the center device and start operating according to the parameters. There is an effect.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a terminal device applied to an embodiment of the present invention, FIG. 2 is a block diagram of a center device applied to an embodiment of the present invention, and FIG. 3 is a system block diagram to which the present invention is applied. FIG. 4 is a time chart 17 showing the operation of the embodiment of the present invention. Explanation of symbols of main parts 2.9... Reception control circuit 3.8... Memory circuit

Claims (1)

[Claims] A data transmission method in a two-way CATV communication system for transmitting data between a center device and a terminal device, wherein the center device transmits parameters necessary for each operation to each terminal device. After the data collection command is sent to each terminal device, the terminal device detects whether or not the parameter is stored in response to the data collection command, and if it is not stored, the data collection command is sent to each terminal device. A data transmission system characterized in that a loss signal is sent to the center device, and in response to reception of the parameter loss signal, the center device retransmits necessary parameters to the corresponding terminal device. .