US4599649A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Synchronous circuit
Assignee: Funai Electric Co Ltd
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Filing: 1984-03-06
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Granted: 1986-07-08
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Expires: 2004-03-06
Abstract
Abstract A synchronous circuit useful for video games and the like is employed to coincide an external video signal in synchronization with an internally-generated video signal. The external signal may be produced by a laser disc playing device, or by other devices. The synchronous circuit reduces the time period for synchronization and eliminates jitter on the external synchronizing signal. A flip-flop circuit element is employed, together with a horizontal synchronizing signal counter having a cycle period somewhat smaller than that of an external horizontal synchronizing signal. The flip-flop circuit element is connected at one input terminal to an output stage of a counter output through a reset line.
Inventors
- 👤 Tetsuro Funai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:04
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/04; H04N5/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
155 words
A synchronous circuit used to coincide an external video signal from a laser disc, for example, with a video signal generated by an internal computer characterized in that an input terminal 1 for an external horizontal synchronizing signal is connected to the S terminal of a R-S flip-flop circuit 4, an output stage of said R-S flip-flop circuit 4 is connected to one input terminal at an AND circuit 7, an oscillator 8 is connected to the other input terminal at said AND circuit 7, a horizontal synchronizing signal counter 9 is connected to the output stage of said AND circuit 7, and output stage of said counter 9 is connected to the R terminal at said R-S flip-flop circuit 4 through a reset line 10 and to an internal horizontal synchronizing signal line 11, and a cycle period of said counter 9 is set somewhat smaller than that of said external horizontal synchronizing signal.
Claim 2
Dependent Claim
155 words
A synchronous circuit used to coincide an external video signal from a laser disc, for example, with a video signal generated by an internal computer characterized in that an input terminal 1 for an external horizontal synchronizing signal is connected to the S terminal of a R-S flip-flop circuit 4, an output stage of said R-S flip-flop circuit 4 is connected to one input terminal at an AND circuit 7, an oscillator 8 is connected to the other input terminal at said AND circuit 7, a horizontal synchronizing signal counter 9 is connected to the output stage of said AND circuit 7, and output stage of said counter 9 is connected to the R terminal at said R-S flip-flop circuit 4 through a reset line 10 and to an internal horizontal synchronizing signal line 11, and a cycle period of said counter 9 is set somewhat smaller than that of said external horizontal synchronizing signal.
References Cited (Backward Citations)
US4517587A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-07 | 1990-01-06 | 1990-07-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-07 | 1994-01-06 | 1994-07-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-07 | 1998-01-06 | 1998-07-08 | $7700.00 | Window Closed / Lapsed |