Patent US5521866A successfully refreshed from Google Patents.
Patent US5712688A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5712688A Expired / Lapsed US ⏱️ 0.0 years remaining

Video controller for displaying computer generated images on a television set

Assignee: Cirrus Logic Inc
•
Filing: 1996-12-03
•
Granted: 1998-01-27
•
Expires: 2016-12-03
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In a graphics card of a computer, a circuit is provided for displaying graphic presentations generated by the card on an external TV set. A TV adapter controls a horizontal state machine of a CRT controller so as to delay generation of CRT timing signals by a time period variable with horizontal lines. As a result, a composite video signal is provided with a time-base variable front porch to simulate VTR video signals. In response to the generated composite video signal, the TV set switches into a VTR mode to disable a comb filter used for separating luminance and chrominance components of a broadcast television signal.

Inventors

  • 👤 Alexander J. Eglit

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 09:07
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/44; G; G09; G09G; G09G1/00; G09G1/28; G09G1/285; H04N21/00; H04N21/40; H04N21/41; H04N21/4104; H04N21/4113; H04N9/00; H04N9/64; H04N9/641

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 125 words
A video controller for enabling computer generated images to be displayed on a video monitor having a circuit for processing broadcast television signals, comprising: a state machine responsive to control circuitry of a computer for generating timing signals to define components of a video signal supplied to said video monitor to display said computer generated images, a delay circuit responsive to an output signal of said state machine for generating a control signal delayed by a variable delay time with respect to said output signal, said delay time being variable with horizontal lines, and a feedback circuit responsive to said control signal for controlling said state machine to generate a control component in said video signal to disable said circuit for processing broadcast television signals.
Claim 2
Dependent Claim 125 words
A video controller for enabling computer generated images to be displayed on a video monitor having a circuit for processing broadcast television signals, comprising: a state machine responsive to control circuitry of a computer for generating timing signals to define components of a video signal supplied to said video monitor to display said computer generated images, a delay circuit responsive to an output signal of said state machine for generating a control signal delayed by a variable delay time with respect to said output signal, said delay time being variable with horizontal lines, and a feedback circuit responsive to said control signal for controlling said state machine to generate a control component in said video signal to disable said circuit for processing broadcast television signals.
Claim 3
Dependent Claim 37 words
The controller of claim 1, wherein said delay circuit comprises a plurality of flip-flop circuits connected in series between a horizontal display enabling output of said state machine and a multiplexer controlled by a horizontal line count.
Claim 4
Dependent Claim 21 words
The controller of claim 2, wherein said multiplexer has a plurality of inputs respectively coupled to outputs of said flip-flop circuits.
Claim 5
Dependent Claim 23 words
The controller of claim 3 further comprising means for supplying said state machine and each of said flip-flop circuits with horizontal clock signals.
Claim 6
Dependent Claim 30 words
The controller of claim 4 further comprising means for disabling a horizontal clock input to said state machine in response to said horizontal display enabling output of said state machine.
Claim 7
Dependent Claim 27 words
The controller of claim 5 further comprising means for enabling said horizontal clock input to said state machine in response to an output signal of said multiplexer.
Claim 8
Dependent Claim 24 words
The controller of claim 6 wherein said state machine comprises means for generating a horizontal sync signal in response to said horizontal clock input.

References Cited (Backward Citations)

US5202669A Cited
US4599647A Cited
US4670785A Cited
US4994912A Cited
US5192999A Cited
US5283819A Cited
US5526055A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2001-01-26 2001-07-28 2002-01-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2005-01-26 2005-07-28 2006-01-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2009-01-26 2009-07-28 2010-01-27 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag