GB2239583A

GB2239583A - Communication terminal for displaying video information

Info

Publication number: GB2239583A
Application number: GB9022207A
Authority: GB
Inventors: Masaaki Nishimura
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 1989-10-18
Filing date: 1990-10-12
Publication date: 1991-07-03
Also published as: JPH03132188A; DE4033126A1; GB9022207D0

Abstract

In a system in which a terminal transmits a request for information to an information centre 20, the centre provides both picture data for display 30 and a picture identifier. The identifier is stored by the terminal in a non-volatile memory 32 so that if there is a power failure it may subsequently be retrieved and transmitted to the centre, whereby information retrieval may be re-commenced at the position previously reached. This is particularly useful if tree type searches are involved. <IMAGE>

Description

j :2 2!:3 5) =S a --3 COMMUNICATION TERMINAL UNIT FOR DISPLAYING VIDEO

INFORMATION This invention relates to a communication terminal unit for displaying video information, such as a user terminal in a Videotex system.

Videotex systems have recently become popular. In these systems, data from information providers are accumlated in an information center and the accumlated information is supplied to users in response to requests from the user's terminals. In these Videotex systems, data are transferred by using a telephone line as the transfer medium.

The user communicates with the information center in an interactive mode by using a communication terminal unit for displaying video information at the user's terminal. The user dials the telephone number of the Videotex service by using a keyboard and transfers information for retrieval 1 from the keyboard. -The user's key operation is decoded by an input controller and supplied to a controller. The controller controls many functions based on:this key input data.

More precisely, first, the user orders the controller to establish a connection between the information center and the communication terminal. The controller then controls the line controller to make the connection. Next, the user requests the transfer of picture data by inputting information for retrieval with the keyboard. The information for retrieval is transferred from the line controller to the information center through a telephone line.

The information center, which contains many kinds of information, transfers the requested picture data to the communication terminal.

As mentioned above, the terminal unit transmits the request for information retrieval, and the information center transmits the data of pictures requested. There may be a direct retrieval method or a tree-type retrieval method used as retrieval methods. In a direct retrieval method, the user points out the number of the picture. In a treetype retrieval method, the user is guided by the pictures transmitted from the information center and the user obtains the picture needed.

The tree-type retrieval method must display many 2 pictures until the user obtains the picture needed. Therefore, the user must conduct complete operations for connecting the line and retrieving a series of pictures to obtain the picture needed. If the power of. the terminal unit is shut down by a power failure while the user retrieves information, the user has to repeat these operations to reobtain the picture which was obtained before the power failure. These operations are very troublesome and may require much time to repeat.

The present invention seeks to provide an improved communication terminal unit and a method of displaying video information on a display of a communication terminal unit which at least alleviate the stated disadvantages of the known system.

According to a first aspect of the present invention, there is provided a communication terminal unit for displaying video information, which supplies information for retrieval to an information supply device and receives video information having a picture identification data from the device and displays the video information on a display, and which comprises a non-volatile memory means for memorizing the picture identification data of the video information whenever video information is received and a restoring means for reading the picture identification data from the memory means by a restoring operation and supplying the data to the information supply device.

According to a second aspect of the present invention, there is provided a method of displaying video information, having picture identification data, on a display of a communication terminal unit, which comprises-the steps of supplying information for retrieval to an information supply device, memorizing the picture identification data of received video information in a non- volatile memory means, reading out the picture identification data from the memory means by using a restoring operation, and supplying the picture identification data as the information for retrieval to the information supply device.

4 -------------11.--------- For a better understanding of the Present invention, reference will now be inade, by way of example, to the accompanying drawings, in which:

Figure 1 provides a block diagram of a communication terminal unit for displaying video information according to the present invention; Figure 2 is a flow chart illustrating the operation of the communication terminal unit shown in Figure 1; Figure 3 illustrates one example of the picture transmitted from the information center; and - Figure 4 illustrates one example of the configuration of the picture transmitted from the information center.

Referring now to Fig. 1, a keyboard 10 has numeral keys, character keys, and associated control keys. The keyboard 10 supplies signals according to the operation of these keys to an input controller 12.

The input controller 12 decodes the signal from the keyboard 10 and supplies key input data to a controller 14. The controller 14 processes for transmission information for 1 picture retrieval according to the key input data from the input controller 12. The controller 14 also decodes receiving data according to a communication protocol. A modulator / demodulator 16 modulates key input data from the input controller 12 through the controller 14 according to a communication format and demodulates picture data from line controller 18. The line controller 18 is-controlled by the controller 14 to connect the line between an information center 20 and the communication terminal unit through a Videotex network 22 by using a telephone line 24 connected to a telephone which is not shown. The Videotex network 22 is a high speed digital transmission line..

A display controller 26 controls a video RAM (random access memory) 28 to memorize the picture data decoded by the controller 14. The display controller 26 reads out the picture data from the video RAM 28 and supplies it to a picture tube 30 synchronously with the raster scanning the picture tube 30.

A non-volatile memory 32 is connected to the controller 14. The memory 32 memorizes a picture identification data supplied from the controller 14, which reads out the picture identification data from the header part of the picture data when the controller 14 receives the picture data. The description of the picture identification data will be given later.

Additionally, in a Videotex system, the line controller 6 i 1 18 may be connected directly to the information center 20 through the telephone line 24 without passing through the Videotex network 22. The information contained in the information center 20 is provided by many kinds of information providers (IP), such as corporations, associations, and individuals.

The communication terminal unit's operation is shown in Fig. 2.

After the power switch is turned on, in step SI, the controller 14 recognizes whether there is an order for dialing by user's key operation from the keyboard 10. If the user operates the dial keys of the keyboard 10 to connect the line between the information center 20 and the communication terminal unit, the dial data is supplied to the controller 14 through the input controller 12. In step S2, the controller 14 controls the line controller 18 to output the signal for line connection. Meanwhile, the information center 20 transmits a response signal to the line controller 18, and the line connection is finished (step S3).

In step S4, the controller 14 judges whether there is a key input from the user. This step S4 waits for the user's key input. If the key input occurs, the operation moves to step S5. In step S5, the controller 14 recognizes whether the key input data indicates that a finish key has been entered. If the finish key is entered, the controller 14 7 - disconnects the line (step S10) and the otion returns to step SI. If the key input data doesn't indicate that the finish key has been entered, the controller 14 supplies data on the user's key operation to the modulator 1 demodulator 16. The modulator 1 demodulator 16 modulates the data and transmits it to the information center 20 through the line controller 18 (step S6). The information center 20. transmits picture data according to the retrieval information. The picture data is transmitted to the modulator / demodulator 16 through the line controller 18, and demodulated to supply it to the controller 14.

In step S7, the controller 14 decodes the received data according to a protocol and supplies the decoded data to the video RAM 28 through the display controller 26. The display controller 26 reads out the picture data accumulated in the video RAM 28, and causes the display tube 30 to display the picture, such as shown in Fig. 3. A picture has a header part 40 which displays the picture identification, etc, and a display part 42 which displays characters of a program (see Fig. 4). The header part 40 has a picture identification area 401 where the picture identification of the program is displayed. The header part 40 also has an area 403 for the name of an information provider and an area 405 for the cost of the information.

The controller 14 reads out the picture identification from the header part of the receiving data (in step S8) and 8 - writes the identification to the non-volatile memory 32 (in step S9). If the information center 20 transmits subsequent picture data in response to key input from the keyboard 10, the controller 14 writes the picture identification of the next picture to the non-volatile memory 32 (in steps S8 and S9). Thus the picture identification of the picture present on the display tube 30 is always in the memory 32.

If the power of the communication terminal unit is interrupted and then restored, the user may display the picture which was displayed when the power was shut off.

To do this, the user operates a restore key on the keyboard 10. The controller 14 judges whether the restore key is operated or not (in step S11). If the restore key is not operated, the controller 14 causes the process to move to ordinary steps S1 to S10 after the power -hasbeen restored. If the restore key is operated, the controller 14 moves to step S12. In step S12, auto-dialing is carried out, and, in step S13, the connection of the line between information center 20 and the communication terminal unit is finished. In the next step S14, the controller 14 reads out the last picture identification data, which is of the picture displayed when the power failure was occured, from the memory 32. The controller 14 transmits the picture identification data as a request for information retrieval to the information center 20. The information center 20 transmits the picture data which corresponds to the picture - 9 identification data transmitted. Then the process moves to step S7.

According to the present invention, the communication terminal unit permits the user to retrieve the picture displayed just before the power failure without troublesome operations, even If the power failure occurred while retrieving information.

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Claims

1. A communication terminal unit for displaying video information, which supplies information for retrieval to an information supply device and receives video information having a picture identification data from the device and displays the video 'Information on a display, comprising: a non-volatile memory means for memorizing the picture identification data of the video information whenever video information is received; and a restoring means for reading the picture identification data from the memory means and supplying the data to the information supply device.

2. A communication terminal unit for displaying video information as claimed in cl-nim 1, wherein the restoring means has a restore key and an auto-dialer for connecting automatically the communication terminal unit and the information supply unit by operation of the restore key.

3. A communication terminal unit for displaying video information as claimed in claim,l or 2, wherein the picture identification data of the video information is in a header part of the picture data.

4. A communication terminal unit for displaying video - 11 as Claimed in -any preceding claim, further cenprising a keyboard for inputting the information for retrieval.

5. A method of displaying video informationhaving picture identification data, on a display of a communication terminal unit, comprising the steps of: supplying inf&A?mation for retrieval to an information supply device; memorizing the picture identification data of received video information in a non-volatile memory means: reading out the picture identification data from the memory means by using a restoring operation; and supplying the picture identification data as the information for retrieval to the information supply device

6. A method of displaying video information on a display of a communication terminal unit as claimed in Claim 5, further including the step of automatically connecting a line between the communication terminal unit and the information supply unit.

7. A c=unication tenninal unit substantially as herein described with reference to. and as sham in, the acocying drawings.

e 12 - Published 1991 atlbe Patent Office. State House. 66171 High Holborn. London WC1R47P. Further copies msy be obtained from Sales Branch. Unit 6. Nine Mile Point Cwmfelinfach. Cross Keys, Ncwport- NPI 7HZ. Printed by Multiplex techniques lid. St Maiy Cray. Kent.