JPH1098701A - Teletext system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To structure a teletext system which is flexibly applicable to arbitrary data and has a high data transmission efficiency. SOLUTION: A teletext signal generating device 10 superposes a teletext signal S1 on a video signal S2, modulates the resulting signal into an RF signal by a modulation part 18, and sends it to a reception device 20. A control part 23 generates a program for operating the reception device 20 by using a program generating process part 25c according to an instruction from an input part 22, and a program transmitting process part 15b sends the signal as a teletext signal to a cable television network L1. The reception device 20 puts the signal back to the original program through a character card 21, a program receiving process part 26b, etc., and stores it in a program area of a program executing process part 26b. After a series of programs is received, the program executing process part 26b executes the programs, and the teletext signal transmitted from the teletext signal generating device 10 is received and displayed at a display part 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a teletext system which is easy to maintain and has high data transmission efficiency.

[0002]

2. Description of the Related Art In a conventional teletext system, in addition to character and graphic data to be displayed on a receiving device, a control code for displaying the data in an arbitrary arrangement is transmitted together with the character and graphic data. Was. Therefore, there is a problem that the transmission data amount becomes twice to five times as compared with the case where only character or graphic data is transmitted. In addition, since the receiving apparatus includes a program capable of decoding only the data of a teletext signal in a certain format as firmware, it is necessary to use R
There is also a problem that OM replacement or the like is required and maintenance is troublesome.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to construct a teletext system which can flexibly deal with arbitrary data and has high data transmission efficiency.

[0004]

According to the present invention, there is provided a teletext signal generator for generating a program which can be executed by a receiver as data to be transmitted and transmitting the program as a teletext signal, and a receiver for receiving and executing the program. To increase the data transmission efficiency by eliminating the need to transmit a control code when transmitting data of a teletext signal by enabling distribution of a program to be executed by the receiving device in addition to data such as characters and graphics. In addition, the maintenance of the receiving device can be easily performed.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a teletext system in which data such as characters and graphics are superimposed on a vertical blanking period of a television signal and transmitted to a receiving device as a teletext signal, a program which can be executed by the receiving device as data to be transmitted is described. A teletext signal generating device that creates and transmits as a teletext signal, and a receiving device that receives and executes the program are provided.
In addition to data such as graphics, it is also possible to distribute a program to be executed by the receiving device.

The receiving apparatus is a general-purpose personal computer to which a circuit board for receiving a text broadcast is added.

[0007] The receiving device includes a program having a predetermined fixed receiving function for receiving a teletext broadcast as firmware.

The transmission path for transmitting the teletext signal is a cable television network.

An identifier indicating the type of the program is added to the data for transmitting the program, so that the type of the program to be received and executed in the plurality of receiving apparatuses can be limited.

[0010] The receiving device is provided with means for creating a program to be distributed to another receiving device, and the program created by the receiving device is passed to the teletext signal generating device and distributed to the other receiving device. I do.

[0011] A physical number is assigned to the receiving device in advance,
The program can be distributed to a specific receiving device.

[0012] The program is divided into a plurality of data and distributed, and the receiving device receives and links the plurality of divided data to form an original program.

The telegram for transmitting the program is of variable length, of the divided telegrams other than the final telegram, the maximum length of a predetermined telegram, and the final telegram is of a length within the maximum length.

The data transmission speed of the transmission path of the teletext signal for distributing the program is approximately 1 Kbyte / sec.

[0015] The program is capable of distributing five programs at the same time, and not simultaneously distributing two or more programs to the same receiving apparatus.

[0016]

FIG. 1 is a block diagram of a teletext system according to the present invention. In the teletext signal generator 10, the superimposing section 17 superimposes the teletext signal S1 composed of data such as characters and graphics in the vertical retrace period of the video signal S2, and superimposes it on the RF signal in the modulation section 18 to provide a cable television. The data is transmitted to the plurality of receiving devices 20, 20,... Via the network L1. The receiving apparatus 20 demodulates the video signal from the RF signal, extracts the character transmission signal, and displays the character transmission signal on the display unit in accordance with a predetermined teletext signal agreement. The control unit 13 of the teletext signal generator 10 includes an input unit 1 such as a keyboard.
The program is set to the program creation mode in response to an instruction from the program 2. In the program creation mode, the control unit 13 creates a program for operating the receiving device 20 by input from the input unit 12 according to the procedure of the program creation processing unit 15a. The created program is converted into a teletext signal by the procedure of the program transmission processing unit 15b and transmitted to the cable television network L1 via the switching unit 16 in the same manner as described above. In a receiving device 20 including a general-purpose personal computer or the like, a character card 21 which is a circuit board for teletext reception having a function of demodulating a teletext signal from an RF signal transmitted via the cable television network L1 is used. The broadcast signal is stored as an original program in the program area of the program execution processing unit 26b according to the procedure of the program reception processing unit 26a. After receiving the series of programs, the control unit 23 causes the program to be executed according to the procedure of the program execution processing unit 26b, receives the teletext signal transmitted from the teletext signal generator 10, and displays it on the display unit 25. Is performed.

In the receiving apparatus 20, a program having a predetermined predetermined receiving function for receiving teletext can be stored in the teletext reception processing section 26d as firmware.

FIG. 2 is a schematic diagram of the data structure of a program transmitted in the teletext system according to the present invention. Ancillary information 30a such as a program length is attached to the head of the series of programs 30b, and a CRC (Cyclic Redundanc) is attached to the back.
y Check) 30c is added as the program data 30 to be transmitted. .

The program data 30 is divided and distributed to a plurality of data 41, 42,..., And the receiving device 20 receives the plurality of divided data 41, 42,. Program 30.

The data 41, 42,... Of the messages transmitting the program data 30 are of variable length, and the maximum length of a predetermined message, for example 10
It is assumed that 31-byte data 41, 42,..., 45, and the final message is message data 46 having a length within the maximum length.
The header part 4 is provided at the head of the data 41, 42,.
1a,... And checksum (CS) 41b are added.
An identifier indicating the type of the program 30b is added to the headers 41a,.
The type of a program to be received and executed within 0,... Can be limited. Also, the receiving devices 20, 20,.
Are assigned a physical number in advance, and the header part 41a,
It is also possible to designate the physical number as the information of and to distribute the program to a specific receiving device 20.

The data transmission speed in the cable television network L1, which is a transmission path of a teletext signal for distributing the program data 30, has a capacity of about 5 Kbytes / sec. However, in order to secure data processing and storage time in the receiving device 20, this is set to approximately 1 Kbyte / sec. in this case,
Five programs can be distributed at the same time. However, for the above reason, the distribution of two or more programs to the same receiving device 20 is not performed at the same time.

The receiving device 20 includes other receiving devices 20, 2
A means for creating a program to be distributed to the receivers 0,... Is provided so that the program created by the receiver 20 can be passed to the teletext signal generator 10 and distributed to other receivers 20, 20,. In accordance with an input from an input unit 22 such as a keyboard provided in the receiving device 20, the control unit 2
3. A program for operating the receiving devices 20, 20,... As described above is created by the program creation processing unit 26c. The created program is, for example, FDD (Floppy D
isc Drive) 24 and stored in a floppy disk and passed to the teletext signal generator 10 to transmit the teletext signal generator 1
0 is stored in the same device from the FDD 14.

[0023]

The present invention is embodied in the form described above, and has the following effects.

A teletext signal generator for generating a program that can be executed by the receiver as data to be transmitted and transmitting the program as a teletext signal, and a receiver for receiving and executing the program are provided. In addition to the above, by enabling distribution of a program to be executed by the receiving device, transmission of a control code when transmitting data of a teletext signal becomes unnecessary, so that the amount of transmission data on a transmission path can be reduced, and transmission can be reduced. Efficiency increases, and conversely traffic on the transmission line decreases. In addition, since the functions of a plurality of receiving devices can be freely changed simultaneously from a remote location, maintenance of the receiving devices is facilitated.

The receiving device is a general-purpose personal computer to which a circuit board for receiving teletext broadcasting is added, so that the intended receiving device can be obtained at low cost and the above program can be created.

The receiving device is provided with a program having a predetermined fixed receiving function for receiving a teletext broadcast as firmware, so that a general-purpose program or the like can be operated without being transmitted from the character signal generating device.

By using a cable television network as a transmission path for transmitting a teletext signal, the above-mentioned object can be achieved with existing equipment.

An identifier representing the type of the program is added to the data for transmitting the program, so that the type of the program to be received and executed in the plurality of receiving devices can be limited, so that the type of the program according to the capability of the receiving device can be determined. Thus, for example, a receiving device with a small memory capacity can flexibly cope with receiving and executing only a short program.

The receiving device is provided with means for creating a program to be distributed to another receiving device, and the program created by the receiving device is passed to the teletext signal generating device and distributed to the other receiving device. This enables the receiving apparatus to perform maintenance change of another receiving apparatus.

A physical number is assigned to the receiving device in advance, and the program can be distributed to the specific receiving device so that the maintenance of only the specific receiving device can be changed.

The program is divided into a plurality of data and distributed, and the receiving apparatus receives the plurality of divided data and connects them to form the original program, thereby ensuring the reliability of the data on the transmission path. .

The telegram for transmitting the program is of variable length,
By setting the maximum length of a predetermined message other than the final message among the divided messages and setting the final message to a length within the maximum length, a program of an arbitrary length can be transmitted efficiently.

By setting the data transmission speed of the transmission line of the teletext signal for distributing the program to approximately 1 Kbyte / sec, the data transmission speed matches the reception processing capability of the receiving device constructed by a general-purpose personal computer.

The program is capable of simultaneously distributing five programs and not simultaneously distributing two or more programs to the same receiving device, thereby matching the processing capability of the receiving device. Data transmission can be performed at the transmission speed, and the transmission capability of the transmission path of the teletext signal can be fully utilized.

[Brief description of the drawings]

FIG. 1 is a block diagram of a teletext system according to the present invention.

FIG. 2 is a schematic diagram of a data structure of a program transmitted in the teletext system according to the present invention.

[Explanation of symbols]

 Reference Signs List 10 Teletext signal generator 11 Display unit 12 Input unit 13 Control unit 14 FDD (Floppy Disc Drive) 15a Program creation processing unit 16b Program transmission processing unit 17 Superposition unit 18 Modulation unit S1 Teletext signal S2 Video signal L1 Cable television network 20 Receiving device 21 Character card 22 Input unit 23 Control unit 24 FDD (Floppy Disc Drive) 25 Display unit 26a Program reception processing unit 26b Program execution processing unit 26c Program creation processing unit 26d Text broadcast reception processing unit

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Taketo Kono 1116 Suenaga, Takatsu-ku, Kawasaki City Inside Fujitsu General Limited

Claims (11)

[Claims] 1. In a teletext system for superimposing data such as text and graphics on a vertical blanking period of a television signal and transmitting the teletext as a teletext signal to the receiving device, a program which can be executed by the receiving device as data to be transmitted is created. And a receiving device for receiving and executing the program, thereby enabling distribution of a program to be executed by the receiving device in addition to data such as characters and graphics. Teletext broadcasting system characterized by that. 2. The teletext system according to claim 1, wherein the receiving device is a general-purpose personal computer to which a circuit board for receiving teletext is added. 3. The teletext system according to claim 2, wherein the receiving device includes, as firmware, a program having a predetermined predetermined receiving function for teletext reception. 4. A transmission path for transmitting the teletext signal,
The teletext system according to claim 1, wherein the teletext system is a cable television network. 5. The method according to claim 1, wherein an identifier indicating a type of the program is added to data for transmitting the program, so that the type of the program received and executed in the plurality of receiving apparatuses can be limited. The teletext system according to claim 1. 6. The receiving device includes means for creating a program to be distributed to another receiving device, and transfers the program created by the receiving device to the teletext signal generating device and distributes the program to another receiving device. 2. The teletext system according to claim 1, wherein 7. The teletext system according to claim 1, wherein a physical number is assigned to the receiving device in advance, and the program can be distributed to a specific receiving device. 8. The program according to claim 1, wherein the program is divided into a plurality of data and distributed, and the receiving device receives and links the plurality of divided data to form an original program. Teletext system. 9. A telegram for transmitting the program may be of variable length, a maximum length of a predetermined telegram other than the final telegram among the divided telegrams, and a final telegram having a length within the maximum length. 2. The teletext system according to claim 1, wherein: 10. The teletext system according to claim 1, wherein a data transmission speed of a teletext signal transmission path for distributing the program is approximately 1 Kbyte / sec. 11. The program according to claim 1, wherein five programs can be distributed at the same time, and two or more programs are not distributed to the same receiving device at the same time. The teletext system described.