Electrical computers and digital data processing systems: input/ – Input/output data processing – Peripheral adapting
Reexamination Certificate
1998-04-21
2001-07-03
Shin, Christopher B. (Department: 2782)
Electrical computers and digital data processing systems: input/
Input/output data processing
Peripheral adapting
C710S072000
Reexamination Certificate
active
06256686
ABSTRACT:
CROSS-REFERENCE TO RELATED APPLICATIONS
Not applicable.
STATEMENT REGARDING FEDERALLY FUNDED RESEARCH OR DEVELOPMENT
Not applicable.
BACKGROUND OF THE INVENTION
The present invention relates to the transmission of serial video signals, and more particularly to a bi-directional serial video port for coupling a serial digital video signal to/from a cable, such as a coaxial cable.
Typically digital video hardware, such as the Profile Professional Digital Recorder (PDR) manufactured by Tektronix, Inc. of Beaverton, Oreg., has dedicated ports for the input and output of serial digital video signals to/from the hardware. In the Profile PDR, for example, an input/output board may have four ports—two for input and two for output. In order to have a specified number of outputs, such as six, three such boards are required even though only two inputs may be required—a total of twelve ports where only eight are required. Alternatively several different boards may have to be designed, such as boards with all output ports or combinations thereof, rather than one standard one to provide the required configuration for the hardware. Also if one of the ports becomes unusable due to some sort of failure, it is not possible to add another port of the same type without replacing the board upon which the failed port resides, which could result in unacceptable down time for the hardware.
What is desired is a bi-directional serial video port for coupling a serial digital video signal to/from a cable that may be configured as either an input port or an output port depending upon hardware requirements.
BRIEF SUMMARY OF THE INVENTION
Accordingly the present invention provides a bi-directional serial video port for coupling a serial digital video signal to/from a cable, such as a coaxial cable, that is configurable as either an input port or an output port. A digital video signal from a digital video source is serialized, if in parallel form, and input to a cable driver as a complementary serial digital video signal pair. At the output of the cable driver is a D.C. blocking capacitor, to remove any D.C. component from the serial digital video signal, and an impedance matching resistor in series with a port connector, such as a coaxial BNC connector. The port connector is also coupled via a decoupling capacitor to an equalization receiver. The equalization receiver is always active for receiving serial digital video signals, but the resulting output may be disabled when the port is configured as an output port. Alternatively when the port is configured as an input port, the output from the cable driver is disabled “low”, the impedance matching resistor serves as a cable termination, and the output from the receiver is enabled.
The objects, advantages and other novel features of the present invention are apparent from the following detailed description when read in conjunction with the appended claims and attached drawing.
REFERENCES:
patent: 4349870 (1982-09-01), Shaw et al.
patent: 4402067 (1983-08-01), Moss et al.
patent: 4582170 (1986-04-01), Horiuchi
patent: 4677467 (1987-06-01), Hayes
patent: 4703198 (1987-10-01), Porter et al.
patent: 5043606 (1991-08-01), Lewis
patent: 5428800 (1995-06-01), Hsieh et al.
patent: 5602494 (1997-02-01), Sundstrom
patent: 5604450 (1997-02-01), Borkar et al.
patent: 5666491 (1997-09-01), Harris, Jr. et al.
patent: 5687387 (1997-11-01), Endejan et al.
patent: 5781927 (1998-07-01), Wu et al.
patent: 5910909 (1999-06-01), Purcell et al.
patent: 5929928 (1999-07-01), Matsugami et al.
patent: 5949473 (1999-09-01), Goodman
patent: 5959678 (1999-09-01), Callahan et al.
patent: 0952515A2 (0000-01-01), None
patent: 2173077A (0000-01-01), None
“Sandar AD-2000 Digital Audio Routing Switchers”, Sandar Electronics a/s P. Box 2004, N-3202 Sandefjord, Norway.
Grass Valley (US) Inc.
Kenyon & Kenyon
Shin Christopher B.
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