Apparatus for storing data broadcast in digital form for generating a character display or for recording such data for later playback

• US 4,016,361 A
• Filed: 09/02/1975
• Issued: 04/05/1977
• Est. Priority Date: 09/26/1974
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Pandey, Kailash Narain
• Primary Examiner(s): Martin, John C.
• Application Number:
  US05/609,654
• Time in Patent Office: 581 Days
• Field of Search: 178/5.6, 178/5.8, 178/DIG. 22, 178/DIG. 23, 178/DIG. 13, 178/6.6 DD, 178/6.6 R, 360/33, 360/9, 360/10
• US Class Current: 348/476
• CPC Class Codes: G06F 3/153 using cathode-ray tubes
• CPC Class Codes: G09G 5/222 Control of the character-code memory
• CPC Class Codes: H04N 5/9207 for teletext
• CPC Class Codes: H04N 7/0882 for the transmission of character code signals, e.g. for teletext circuits for the digital non-picture data signal H04N7/035

Abstract

Apparatus for use in conjunction with a television broadcast receiver for storing, in a main memory, digital data transmitted during portions of the transmitted video signals not used for picture signal content. The digital data is extracted at the receiver at a high data rate and stored in the main memory. The stored data may be used, under viewer control, to generate a character display on the display tube of the receiver. Alternatively, the data content of the main store may be written into a first buffer store from which data is read out at a slow rate and stored by a low frequency signal recorder. Data signals may subsequently be read out from that recorder (or from a separate recorder on which suitable data signals have independently been recorded) into a second buffer store from which they are inputted at a high data rate into the main memory for generation of a display. By use of such apparatus, information represented by the received digital data may be accumulated in the main memory for viewer-controlled display or recorded by a low frequency recorder for retention and subsequent replay. Additionally, information from other sources suitably recorded on a low frequency recorder may be entered into the main memory for display by the receiver.

Claims

1. Data handling apparatus for use in conjunction with a television receiver;

said apparatus including means for selecting parts of a television signal received by said receiver, deriving data from said selected parts and applying said data at a high data rate to a main high speed storage means for the data;

means for selectively reading data from said main storage means and for producing therefrom video signals for generating a legible display of the selected data;

first buffer storage means for receiving data from the main storage means, a group of digits at a time;

means for reading data at low speed from said buffer storage means and producing therefrom signals suitable for recording by a relatively low frequency signal recorder;

means for deriving data signals from signals from a relatively low frequency signal recorder; and

second buffer storage means for receiving the derived data signals and for producing therefrom data signals at a high data rate, a group of digits at a time, and for applying said digit groups to said main storage means.

2. Apparatus according to claim 1, wherein said data derived from the selected parts of said television signal is in serial binary coded from in which a group of binary digits represents a character;

and said means for producing video signals in response to the binary coded data is adapted to receive a group of digits at a time to generate video signals representing parts of characters represented by said groups of digits.

3. Apparatus according to claim 2, wherein said main storage means is arranged to store said groups of digits in parallel, with the data derived from a single field of said television signal stored sequentially;

said main storage means being arranged to recirculate the data stored in it with a cycle time equal to the line scan period of the television signal.

4. Apparatus according to claim 3, wherein each said character is represented by six digits and each said group of digits includes a further digit in the form of a parity check digit.

5. Apparatus according to claim 1, wherein both of said buffer storage means are provided by a single buffer store.

6. Apparatus according to claim 3, wherein the first buffer storage means is arranged to receive a group of digits in parallel and arranged to output the digits in serial form at a rate suitable for recording by a low frequency signal recorder;

and the second buffer storage means is arranged to receive signals derived from a low frequency signal recorder in serial form and produce therefrom groups of digits in parallel.

7. In combination with television broadcast receiving apparatus for receiving broadcast television signals each comprising first and second signal portions, said first signal portions including video signal information for controlling generation of a picture to be displayed by display means of said receiver by a series of line scans over each of a succession of fields of said television signal, and said second signal portions including digital data signals;

a. means for selectively extracting said digital data signals from said second signal portions, said extracted digital data signals being in serial binary coded form in which a group of binary digits represents a character;

b. means for applying said extracted signals at a high data rate to a main high speed storage means for storage of said groups of digits in parallel with data signals extracted from a single field of a said television signal stored sequentially, said main storage means adapted to recirculate data signals stored therein with a cycle time equal to the line scan period of said television signal;

c. means for selectively reading respective groups of data signals from said main storage means to produce video signals representing parts of characters represented by said groups of digits, for generation of a legible display of said selected data by said display means;

d. first buffer storage means selectively connectible to said main storage means for receiving groups of digit signals, a group at a time, in parallel and for outputting said digit signals in serial form;

e. means for reading said serial digital signals from said first buffer storage means at a low data rate for recording by low frequency signal recorder means;

f. means for deriving digital data signals from low frequency signal recorder means and for inputting said data signals in serial form to second buffer storage means; and

g. means for outputting from said second buffer storage means, groups of stored digits in parallel, a group at a time, at a high data rate and for inputting said digit groups to said main storage means.

8. The combination set forth in claim 7, further including manually operable means for establishing a signal path for generation of a picture by said display means in response to said first portions of said television signals and alternatively establishing a signal path for generation of a picture by said display means comprising sets of characters in response to said video signals representing parts of characters.

9. The combination as set forth in claim 7. wherein said low frequency signal recorder means recited in Clause e. and said low frequency signal recorder means recited in Clause f are provided by a single signal recorder.

10. The combination as set forth in Claim 7, wherein said first and second buffer storage means are provided by a single buffer store.