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US3573787A Expired / Lapsed US ⏱️ 0.0 years remaining

Generator for video signal for reproduction of characters by television receiver

Assignee: Motorola Solutions Inc
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Filing: 1968-01-31
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Granted: 1971-04-06
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Expires: 1988-01-31
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Abstract

Abstract Character generator for developing a video signal for application to a television receiver to reproduce characters on the tube screen by a dot matrix. The signal representing each character actuates a plurality of gates for horizontal lines which are operated in turn, and each selectively triggers a set of gates associated with the dot positions along the lines which are operated in turn to produce video components which are combined to form the video signal.

Inventors

  • 👤 George E Sandgren
  • 👤 William Milleker

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-22 20:11
CPC Classifications
G; G09; G09G; G09G5/00; G09G5/22; G09G5/24

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 324 words
A system for generating a video signal for application to a television receiver to display characters on the cathode ray tube thereof in the form of a matrix having a width of N dots and a height of M rows of dots, such systems including in combination, input means having a plurality of terminals providing in sequence signals representing particular characters, M first gates associated with each character and each having first and second inputs with said first input coupled to the one of said terminals for such character for receiving the signals therefrom, first counter means having N outputs individually connected to said second inputs of said first gates for all the characters and applying pulse signals thereto for rendering said first gates conducting in turn, N second gates having a plurality of inputs and providing an output in response to a signal at any one of said inputs, means connecting said outputs of said first gates for each character to said inputs of predetermined ones of said second gates to produce signals representing the dots of the individual rows forming such character, N third gates each having first and second inputs with said first input coupled respectively to the output of one of said second gates, fourth gate means having N inputs connected to the outputs of said third gates, and second counter means having N outputs connected individually to said second inputs of said third gates and applying pulse signals thereto for rendering said third gates conductive in turn to apply signals to said fourth gate means, said second counter means providing pulses at a repetition rate at least 40 times the repetition rate of said first counter means so that said fourth gate means applies a video signals forming dots in a line as said third gates are rendered conducting, and said first gates provide signals in turn to said second gates for controlling the video signal for successive lines.
Claim 2
Independent Claim 324 words
A system for generating a video signal for application to a television receiver to display characters on the cathode ray tube thereof in the form of a matrix having a width of N dots and a height of M rows of dots, such systems including in combination, input means having a plurality of terminals providing in sequence signals representing particular characters, M first gates associated with each character and each having first and second inputs with said first input coupled to the one of said terminals for such character for receiving the signals therefrom, first counter means having N outputs individually connected to said second inputs of said first gates for all the characters and applying pulse signals thereto for rendering said first gates conducting in turn, N second gates having a plurality of inputs and providing an output in response to a signal at any one of said inputs, means connecting said outputs of said first gates for each character to said inputs of predetermined ones of said second gates to produce signals representing the dots of the individual rows forming such character, N third gates each having first and second inputs with said first input coupled respectively to the output of one of said second gates, fourth gate means having N inputs connected to the outputs of said third gates, and second counter means having N outputs connected individually to said second inputs of said third gates and applying pulse signals thereto for rendering said third gates conductive in turn to apply signals to said fourth gate means, said second counter means providing pulses at a repetition rate at least 40 times the repetition rate of said first counter means so that said fourth gate means applies a video signals forming dots in a line as said third gates are rendered conducting, and said first gates provide signals in turn to said second gates for controlling the video signal for successive lines.
Claim 3
Dependent Claim 46 words
A system in accordance with claim 1 wherein said input means includes a detector for each character, and each of said detectors has an input for receiving a coded signal and an output connected to said terminal of said input means associated with the particular character.
Claim 4
Dependent Claim 23 words
A system in accordance with claim 2 including inverter means connected between each detector of said input means and the associated terminal thereof.
Claim 5
Dependent Claim 39 words
A system in accordance with claim 1 including memory means connected between the outputs of said second gates and the inputs of said third gates, and means connecting said second counter to said memory means for resetting the same.
Claim 6
Dependent Claim 45 words
A system in accordance with claim 4 wherein said memory means includes a flip-flop circuit connected between the output of each second gate and one input of the respective third gate, and means connecting said second counter to said flip-flop circuits for resetting the same.
Claim 7
Dependent Claim 35 words
A system in accordance with claim 1 wherein said first gates and NAND gates, said second gates are NOR gates, said third gates are NAND gates and said fourth gate means is a NOR gate.
Claim 8
Dependent Claim 25 words
A system in accordance with claim 6 including an inverter connecting the output of each second gate to one input of the respective third gate.
Claim 9
Dependent Claim 50 words
A system in accordance with claim 6 including an inverter connected to the output of each second gate, a flip-flop circuit connecting each of said inverters to one input of the respective third gate, and means connecting said second counter to each of said flip-flop circuits for resetting the same.
Claim 10
Independent Claim 250 words
A system for generating a video signal for application to a television receiver to display characters on the cathode ray tube thereof in the form of line segments having N dot pOsitions along the line and a height of M line segments, and with each line segment having dots in particular positions, such system including in combination, input means having a plurality of terminals providing signals representing particular characters, M first gates connected to each terminal with said gates being individually associated with the M line segments for the character represented by such terminal, counter means connected to said M first gates for each character and applying signals thereto for rendering said first gates operative in turn, N second gates representing the N dot positions in a line segment and having a plurality of inputs and providing an output in response to a signal at any one of said inputs, a plurality of circuit means each connected to said inputs of predetermined ones of said second gates which represent the dot positions for a particular line segment, means connecting the output of each of said first gates to one of said circuit means to actuate said second gates for the particular line segment, N third gates coupled respectively to the outputs of said second gates, and counter means connected to said third gates and applying signals thereto for rendering said third gates operative in turn to provide signals for producing dots in sequence in positions for a particular line segment.
Claim 11
Independent Claim 250 words
A system for generating a video signal for application to a television receiver to display characters on the cathode ray tube thereof in the form of line segments having N dot pOsitions along the line and a height of M line segments, and with each line segment having dots in particular positions, such system including in combination, input means having a plurality of terminals providing signals representing particular characters, M first gates connected to each terminal with said gates being individually associated with the M line segments for the character represented by such terminal, counter means connected to said M first gates for each character and applying signals thereto for rendering said first gates operative in turn, N second gates representing the N dot positions in a line segment and having a plurality of inputs and providing an output in response to a signal at any one of said inputs, a plurality of circuit means each connected to said inputs of predetermined ones of said second gates which represent the dot positions for a particular line segment, means connecting the output of each of said first gates to one of said circuit means to actuate said second gates for the particular line segment, N third gates coupled respectively to the outputs of said second gates, and counter means connected to said third gates and applying signals thereto for rendering said third gates operative in turn to provide signals for producing dots in sequence in positions for a particular line segment.
Claim 12
Dependent Claim 39 words
A system in accordance with claim 9 wherein said first gates are rendered operative at a relatively slow rate so that said third gates provide signals for a plurality of line segments between successive operations of said first gates.

References Cited (Backward Citations)

US3011153A Cited
US3345458A Cited
US3388391A Cited
US3444319A Cited
US3439219A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1974-04-05 1974-10-05 1975-04-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1978-04-05 1978-10-05 1979-04-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1982-04-05 1982-10-05 1983-04-06 $7700.00 Window Closed / Lapsed

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