Data access system wherein subscriber terminals gain access to a data bank by telephone lines

• US 4,253,157 A
• Filed: 09/29/1978
• Issued: 02/24/1981
• Est. Priority Date: 09/29/1978
• Status: Expired due to Term

• Current Assignee: Alpex Computer Corp.
• Original Assignee: Alpex Computer Corp.
• Inventors: Kirschner, Wallace, Haskel, Lawrence M.
• Primary Examiner(s): Springborn, Harvey E.
• Application Number:
  US05/947,699
• Time in Patent Office: 879 Days
• Field of Search: 364/200 MS, 364/900 MS, 179/2 CA, 179/2 DP, 179/18 BH, 179/18 DA, 340/152 R, 340/152 T, 340/153, 340/154
• US Class Current: 1/1
• CPC Class Codes: H04M 11/085 using a television receiver, e.g. viewdata system

Abstract

A data access system comprises a plurality of intelligent terminals capable of selectively receiving data from a data bank by means of barge-in telephone lines. Each terminal includes a basic terminal into which application modules and device control modules may be plugged. The application modules contain programs enabling the computer to perform specified functions in conjunction with certain stored subroutines within the basic terminal. A device control module enables communication by telephone with the data bank. A terminal subscribes to the data bank by transferring selectively subscription data to memory within the terminal. In one embodiment, subscription data identifying by serial numbers the terminals which are to become subscribers is circulated on subscription barge-in telephone lines. If a terminal calls a subscription line on which there appears the serial number for that terminal, the subscription data for that terminal is permanently stored within the application module of the terminal. The text data to which the terminal has subscribed is retrieved from the data bank by calling a barge-in telephone line (on which such data is circulated) if the stored subscription data shows that the subscription is in effect.

Claims

1. A data retrieval system for enabling subscribers to retrieve and display selected text data, comprising in combination

a data bank,

a plurality of text barge-in telephone lines on which text data from said data bank is circulated, said text data including text identifying signals,

a subscription barge-in telephone line on which subscription data for a multiplicity of subscribers is circulated, said subscription data identifying subscriber terminals which have subscribed to the text data and the text data to which they have subscribed, and

a multiplicity of subscriber terminals, each of which includes data processor means, memory means and display means, said data processor means under control of instructions stored in said memory means determining the information to be displayed by said display means, each one of said subscriber terminals further including

means for transferring subscription data for said one subscriber terminal only from said subscription barge-in telephone line to a first portion of said memory means,

means for comparing selected text identifying signals on at least one of said text barge-in telephone lines and said subscription data;

and

means for selectively causing the text data on said one text barge-in telephone line to be displayed when said means for comparing indicates that said one subscriber terminal has subscribed thereto.

2. A data retrieval system according to claim 1, wherein each subscriber terminal comprises

a basic terminal including said data processor and a second portion of said memory means in which are stored program instructions for controlling the display,

at least one application module physically and electrically detachable from said basic terminal and including a third portion of said memory means having stored therein program instructions defining the function of the terminal, and

a communications module for connecting said terminal to any of said text and subscription barge-in telephone lines.

3. A data retrieval system according to claim 2, wherein said first portion of said memory means which stores the subscription data appearing on said subscription barge-in line comprises an EAROM.

4. A data retrieval system according to claim 3, wherein each of said basic terminals has a unique identifier code permanently stored in a fourth portion of said memory means, said subscription data identifying the terminals which have subscribed to the text data by said identifier codes.

5. A data retrieval system according to claim 1 or 2, wherein

in a special text barge-in telephone line data identifying the services available for subscription is circulated, and

wherein each of said subscriber terminals further includes means for causing the data appearing on said special text barge-in telephone line to be displayed by said display means.

6. For use in a data retrieval system which includes a plurality of text barge-in telephone lines on which text data from a data bank is circulated, a subscriber terminal capable of serving a plurality of preselected separate basic operating functions, comprising

display means,

data processor means,

memory means having stored therein program instructions for operating such data processor means, said program instructions including display instructions for controlling said display means and operating instructions for controlling the basic operating function of the terminal,

said display means displaying text data under control of said display instructions and said data processor means,

means for transferring preselected subscription data to a first portion of said memory means,

means for comparing the stored subscription data in said memory means with identifier signals accompanying said text data to provide an indication whether the terminal has subscribed to said text data, and

means for selectively causing the text data on at least one of said text barge-in telephone lines to be displayed when said comparing means indicates that the terminal has subscribed to said text data.

7. A subscriber terminal according to claim 6, wherein said subscriber terminal comprises

a basic terminal including said data processor means and a second portion of said memory means in which are stored said display instructions,

at least one application module physically and electrically detachable from said basic terminal and including a third portion of said memory means having stored therein said operating instructions, and

a communications module for connecting said terminal to any of said barge-in telephone lines.

8. A subscriber terminal according to claim 7 wherein the first portion of said memory means comprises an EAROM.

9. A subscriber terminal according to claim 8, wherein said basic terminal has a unique identifier code permanently stored in said memory means, said subscription data including the identifier codes of selected subscriber terminals and text identifying signals.

10. A method of retrieving data from a data bank wherein the retrieved data is transmitted via telephone lines and displayed at a terminal, comprising

calling from a terminal a subscription barge-in telephone line on which subscription data from said data bank for a multiplicity of subscribers is circulated,

storing at said terminal the subscription data corresponding to that terminal that is circulated on said subscription barge-in telephone line,

thereafter calling from said terminal a text barge-in telephone line on which text data from said data bank is circulated,

comparing an identifying code accompanying the text data appearing on said text barge-in telephone line with the subscription data stored in the terminal, and

displaying said text data when the aforesaid comparison indicates that there is a predetermined correlation between said identifying code and said stored subscription data signifying that said terminal has subscribed to said text data.