System and method for transferring high-definition multimedia signals over four twisted-pairs

• US 8,098,690 B2
• Filed: 03/18/2008
• Issued: 01/17/2012
• Est. Priority Date: 03/18/2008
• Status: Expired due to Fees

• Current Assignee: Cadence Design Systems Incorporated (Cadence Group)
• Original Assignee: Transwitch Corporation
• Inventors: Roethig, Wolfgang, Bar-Niv, Amir
• Primary Examiner(s): Moe, Aung S
• Assistant Examiner(s): LOUIS, VINNCELAS
• Application Number:
  US12/050,632
• Publication Number:
  US 20090238212A1
• Time in Patent Office: 1,400 Days
• Field of Search: 370/294, 370/486, 370/342, 370/498, 375/140, 375/316, 725/37, 725/118
• US Class Current: 370/498
• CPC Class Codes: G09G 2370/047 using display data channel standard [DDC] communication
• CPC Class Codes: G09G 2370/12 Use of DVI or HDMI protocol in interfaces along the display data pipeline
• CPC Class Codes: G09G 5/006 Details of the interface to the display terminal specific for a display terminal using a CRT G09G1/167; using a flat panel G09G3/2096; circuits for interfacing with colour displays G09G5/04
• CPC Class Codes: H04L 7/0008 Synchronisation information channels, e.g. clock distribution lines
• CPC Class Codes: H04N 21/4122 additional display device, e.g. video projector digital output for controlling a plurality of local displays G06F3/1423
• CPC Class Codes: H04N 21/43632 involving a wired protocol, e.g. IEEE 1394 high-speed IEEE 1394 serial bus H04L12/40052
• CPC Class Codes: H04N 7/163 by receiver means only

Abstract

A system and method for transferring high-definition multimedia signals over four twisted-pairs. The system includes a multimedia source for transmitting multimedia data and source-to-sink management data to a multimedia sink over a first channel, a second channel and a third channel wherein the multimedia source is further being capable of transmitting a clock signal to the multimedia sink over a fourth channel; and a multimedia sink for transferring sink-to-source management data to the multimedia source over the fourth channel. The clock signal and the sink-to-source management data are simultaneously transmitted over the fourth channel. Each of the channels comprises a single twisted-pair, thereby the channels can bounded in a twisted pair type cable comprising at least one of: Category 5, Category 5e, Category 6, and Category 6e.

Claims

1. A system for transferring high definition multimedia signals over a cable having four channels, comprising:

a multimedia source for transmitting multimedia data and source-to-sink management data to a multimedia sink over a first channel, a second channel and a third channel, wherein a transfer rate of the multimedia data is higher than a transfer rate of the source-to-sink management data, the multimedia source includes at least one source multiplexer for, generating the source-to-sink management data by multiplexing a display data channel (DDC) signal and a consumer electronics control (CEC) signal to be transmitted together over a single channel, wherein the single channel is any one of the first channel, the second channel, and the third channel, and wherein the multimedia source is further capable of transmitting a clock signal to the multimedia sink over a fourth channel; and

the multimedia sink for transferring sink-to-source management data to the multimedia source over the fourth channel, wherein a transfer rate of the clock signal is higher than a transfer rate of the sink-to-source management data, the multimedia sink includes a sink multiplexer for generating the sink-to-source management data by multiplexing a DDC signal, a CEC signal, and a hot plug detect (HPD) signal to be transmitted together over the fourth channel, and wherein the sink-to-source management data and the clock signal are simultaneously transferred over the fourth channel, thereby transferring the high definition multimedia signals including the multimedia data, the source-to-sink management data, the sink-to-source management data, and the clock signal over the cable.

2. The system of claim 1, wherein each of the first channel, second channel, third channel and fourth channel comprises a single twisted pair, thereby the signals are transferred over four twisted pairs.

3. The system of claim 2, wherein the four twisted pairs are bounded in a twisted pair type cable comprising at least one of:

Category 5, Category 5e, Category 6, and Category 6e.

4. The system of claim 1, wherein the multimedia source comprises:

a data multiplexing circuit for interleaving the multimedia data and the source-to-sink management data; and

a source clock and data handler for transferring the clock signal over the fourth channel and filtering the sink-to-source management data received on the fourth channel from the multimedia sink.

5. The system of claim 1, wherein the multimedia sink comprises:

a data demultiplexing circuit for de-interleaving the multimedia data and the source-to-sink management data received on the first channel, the second channel, and the third channel; and

a sink clock and data handler for transferring the sink-to-source management data generated by the sink multiplexer over the fourth channel and filtering the clock signal received on the fourth channel from the multimedia source, the sink clock and data handler sink multiplexer.

6. The system of claim 1, wherein the multimedia data comprises at least:

pixel data, audio data, and auxiliary data.

7. The system of claim 1, wherein the source-to-sink management data is transferred as user-defined control codes.

8. The system of claim 1, wherein the signals are at least high-definition multimedia interface (HDMI) signals.

9. The system of claim 8, wherein the multimedia data comprises transition minimized differential signaling (TMDS) characters.

10. A multimedia source adapted to enable the transfer of high definition multimedia signals over a cable having four channels, comprises:

a data multiplexing circuit for transferring multimedia data and source-to-sink management data over a first channel, a second channel, and a third channel, wherein a transfer rate of the multimedia data is higher than a transfer rate of the source-to-sink management data, the multimedia source includes at least a first multiplexer for generating the source-to-sink management data by multiplexing a display data channel (DDC) signal and a consumer electronics control (CEC) signal to be transmitted together over a single channel, wherein the single channel is any one of the first channel, the second channel, and the third channel; and

a source clock and data handler for filtering a sink-to-source management data received on a fourth channel and for transferring a clock signal to a multimedia sink over the fourth channel, wherein the sink-to-source management and the clock signal are simultaneously transmitted over the fourth channel, the sink-to-source management data received on the fourth channel includes a display data channel (DDC) signal, a consumer electronics control (CEC) signal, and a hot plug detect (HDP) signal.

11. The multimedia source of claim 10, wherein each of the first channel, second channel, third channel and fourth channel comprises a single twisted pair, thereby the signals are transferred over four twisted pairs.

12. The multimedia source of claim 11, wherein the four twisted pairs are bounded in a twisted pair type cable comprising at least one of:

Category 5, Category 5e, Category 6, and Category 6e.

13. The multimedia source of claim 10, wherein the data multiplexing circuit comprises:

a second multiplexer for multiplexing the source-to-sink management data with a first stream of the multimedia data;

a third multiplexer for multiplexing the source-to-sink management data with a second stream of the multimedia data; and

a fourth multiplexer for multiplexing the source-to-sink management data with a third stream of the multimedia data.

14. The multimedia source of claim 13, wherein the multimedia data comprises at least one of:

pixel data, audio data, and auxiliary data.

15. The multimedia source of claim 10, wherein the source-to-sink management data is transferred as user-defined control codes.

16. The multimedia source of claim 15, wherein the source clock and data handler comprises:

a low pass filter for filtering the sink-to-source management data;

a demultiplexer for producing signals of the sink-to-source management data; and

a phase-locked loop (PLL) circuit for generating the clock signal.

17. The multimedia source of claim 10, wherein the signals are at least high-definition multimedia interface (HDMI) signals.

18. The multimedia source of claim 17, wherein the multimedia data comprises transition minimized differential signaling (TMDS) characters.

19. A multimedia sink adapted to enable the transfer of high definition multimedia signals over a cable having four channels, comprises:

a data demultiplexing circuit for extracting multimedia data and source-to-sink management data transferred over a first channel, a second channel, and a third channel, wherein the transfer rate of the multimedia data is higher than a transfer rate of the source-to-sink management data, wherein the source-to-sink management data is received on any of the first channel, the second channel, and the third channel and includes a display data channel (DDC) signal and a consumer electronics control (CEC) signal; and

a sink clock and data handler for filtering a clock signal received on a fourth channel and for transferring sink-to-source management data to a multimedia source over the fourth channel, the multimedia sink includes a multiplexer for generating the sink-to-source management data by multiplexing a DDC signal, a CEC signal, and a hot plug detect (HPD) signal to be transmitted together over the fourth channel, wherein the sink-to-source management data and the clock signal are simultaneously transmitted over the fourth channel.

20. The multimedia sink of claim 19, wherein each of the first channel, second channel, third channel and fourth channel comprises a single twisted pair, thereby the signals are transferred over four twisted pairs.

21. The multimedia sink of claim 20, wherein the four twisted pairs are bounded in a twisted pair type cable comprising at least one of:

Category 5, Category 5e, Category 6, and Category 6e.

22. The multimedia sink of claim 19, wherein the data demultiplexing circuit comprises:

a first demultiplexer for demultiplexing the source-to-sink management data and a first stream of the multimedia data;

a second demultiplexer for demultiplexing the source-to-sink management data and a second stream of the multimedia data; and

a third demultiplexer for demultiplexing the source-to-sink management data and a third stream of the multimedia data; and

a fourth demultiplexer for outputting the signals of the source-to-sink management data.

23. The multimedia sink of claim 22, wherein the multimedia data comprises at least one of:

pixel data, audio data, and auxiliary data.

24. The multimedia sink of claim 19, wherein the source-to-sink management data is transferred as user-defined control codes.

25. The multimedia sink of claim 19, wherein the sink clock and data handler comprises:

a high pass filter for filtering the clock signal; and

a phase-locked loop (PLL) circuit for recovering the clock signal.

26. The multimedia sink of claim 19, wherein the signals are at least high-definition multimedia interface (HDMI) signals.

27. The multimedia sink of claim 26, wherein the multimedia data comprises transition minimized differential signaling (TMDS) characters.

28. A method for transferring high definition multimedia signals over a cable having four channels, comprising:

generating source-to-sink management data by multiplexing a display data channel (DDC) signal and a consumer electronics control (CEC) signals to be transmitted together over a single channel;

transferring multimedia data and the source-to-sink management data from a multimedia source to a multimedia sink over a first channel, a second channel, and a third channel of the cable by interleaving the source-to-sink management data and the multimedia data, wherein the transfer rate of the multimedia data is higher than a transfer rate of the source-to-sink management data;

generating sink-to-source management data by multiplexing a DDC signal, a CEC signal, and a hot plug detect (HPD) signal to be transmitted together over a fourth channel of the cable; and

simultaneously transferring the sink-to-source management data and a clock signal over the fourth channel, wherein the sink-to-source management data is transferred from the multimedia sink to the multimedia source and the clock signal is transferred from the multimedia source to the multimedia sink, and wherein a transfer rate of the clock signal is higher than a transfer rate of the sink-to-source management data.

29. The method of claim 28, wherein each of the first channel, second channel, third channel and fourth channel comprises a single twisted-pair, thereby the signals are transferred over four twisted pairs.

30. The method of claim 29, wherein the four twisted pairs are bounded in a twisted pair type cable comprising at least one of:

Category 5, Category 5e, Category 6, and Category 6e.

31. The method of claim 28, further comprising:

demultiplexing the multimedia data and the source-to-sink management data received on the first channel, the second channel, and the third channel;

filtering the clock signal sent on the fourth channel from the multimedia source; and

filtering the sink-to-source management data sent on the fourth channel from the multimedia sink.

32. The method of claim 28, wherein the signals are at least high-definition multimedia interface (HDMI) signals.

33. The method of claim 32, wherein the multimedia data comprises transition minimized differential signaling (TMDS) characters.