JPS6041515B2 - Terminal control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a terminal control system in a system that provides individual information services for image signals.

For example, a bidirectional CA that provides individual information services for image signals.
In the TV system, various information files in the center equipment are controlled by NoriQuest signals from the terminal devices, and image signals, etc. are sent to the corresponding terminal devices through multiple transmission lines. As shown in the figure.

In this system, when requesting information from a terminal device 30, the request device 31 is used to specify the number of the information to be received, and the information is modulated by the terminal control device 32 and transmitted to the center equipment 10 through the transmission path 20. This signal is demodulated by the transmitting/receiving device 11 and sent to the control device 12. The control device 12 determines the demodulated IJ quest signal from the terminal device 30 and sends it to the center equipment 1.
An activation control signal for selecting a corresponding image signal from among the image files 13 within 0 is output, and the image signal is transmitted. This image signal is then modulated and frequency multiplexed by the transmitting/receiving device 11 and sent to the transmission path 20 .
On the other hand, in the terminal device 30, the terminal control device 3i2 separates the downstream signals, the signal selection device 33 extracts a desired signal from the multiplexed signals, and the receiving device 34 reproduces the image signal. The signal selection device 33 demodulates the image signal of a desired channel from among the frequency multiplexed signals, and the channel control of this device 33 is performed using a channel switching command signal sent from the control device 12 of the center equipment 10. It is carried out by Conventional terminal device 3
In controlling the channel 0, the request device 31
The control device 12 sets the corresponding channel number according to the content of the image signal request from the signal selection device 33, and sends the number to the signal selection device 33 to set the channel.

A time chart of this operation is shown in FIG.

At the beginning of the technique, an image request signal from the request device 31 is sent to the control device 12, and the content is determined. As a result, a corresponding transmission channel is determined and a channel setting signal is sent to the signal selection device 33 of the terminal. The control device 12 waits for the response of the channel switching signal from the terminal and activates the transmission to the image floor/'route 3 of the center equipment 10, thereby starting the transmission of the image signal during the daytime. The response time for channel switching from the terminal device 30 may be short, but the response time for channel switching from the terminal device 30 may be short.
Some configurations of 4 include elements that are long.

For example, if a device with mechanical elements such as image memory is introduced into the receiving device in order to receive still images, it will take several seconds for the start-up time, etc., resulting in a long response time for channel switching, and The response time from the point of view of the system also became longer, which was undesirable. This channel switching operation is performed every time an IJ quest from the terminal device 10 occurs, which has the disadvantage of slowing down the response time of the entire service. The present invention centrally manages the state of the signal selection device of each terminal device at the center side, and before the control unit sends a channel switching signal to the terminal device,
By referring to the channel numbers of the terminal device and if they are the same, the image file is activated without sending a channel switching signal, and if the channel numbers are different, the channel switching signal is sent and then the image file is activated. This is a terminal control method that aims to speed up the response time seen from the terminal device. FIG. 3 shows a time chart of the operation according to one embodiment of the present invention. As is clear from the comparison with the conventional method shown in FIG. The effect of shortening response time is significant. FIG. 4 shows an example of a circuit provided in the conventional center equipment 10 to realize the terminal control method according to the present invention.

The terminal status register 41 stores the current channel number of the signal selection device 33 of each terminal device 30. Signal X2 from request device 31 of terminal device 30
is converted by the decoder circuit 42 into a corresponding channel number signal CH and image file address signal AD. When this channel number signal CH is the same as the output signal of the terminal status 41 register, it passes through the AND circuit 43 and is passed through the gate circuit 45 of the image file address signal AD.
is opened and output as the activation signal Y of the image file 13. Next, the channel number signal CH is transmitted to the terminal status 41
When the output signal is different from the output signal of the register, it is outputted as a channel switching signal Z to the terminal arming 30 through the inverting circuit 46. The image file 1 is passed through the OR circuit 44 by the response signal X from the terminal side to this channel switching signal.
It is output as the activation signal Y of No. 3. With the above circuit,
The channel number of the signal selection device 33 of the terminal device 30 is managed centrally using the terminal status 41, and a channel switching signal is output only when the channel number of the signal selection device 33 differs from the request signal, so the response of the entire system is improved. It becomes possible to shorten the time. As described above, the present invention
The status of the image signal selection device of each terminal device is managed centrally using the terminal status provided in the center equipment, and when a NoriQuest signal is generated from the terminal device, the corresponding terminal status is referred to, and the corresponding terminal is sent to the center equipment. An object of the present invention is to provide an excellent terminal control method capable of shortening the response time of the entire system by shortening the response time from the terminal device to the control signal by changing the control signal to the device.

[Brief explanation of drawings]

Figure 1 is a configuration diagram showing a conventional information service system, Figure 2 is a time chart using a conventional terminal control method, and Figure 3 is a diagram showing a conventional information service system.
The figure is a time chart in one embodiment of the terminal control method of the present invention, and FIG. 4 is a circuit configuration diagram of an implementation implementing the terminal control method of the present invention. 10... Center device, 12... Control device, 30... Terminal device, 31... Request device, 33... Signal selection device, 41...
・Terminal status, 42... Decoder circuit, 4
6...Gate circuit. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. The status of the image signal selection device of each terminal device is managed centrally using the terminal status provided in the center equipment, and when a request signal from the terminal device is generated, the state of the image signal selection device of the center equipment is controlled by referring to the corresponding terminal status. A terminal control method characterized by changing a control signal from to a corresponding terminal device.