Patexia seeks prior art for US Patent 7,295,578 (US ‘578), with a focus on claim 8, which allegedly describes a method for transmitting video data and auxiliary data (e.g. audio data, or any other type of data other than video data or timing information) along with their respective clock signals over a transition minimized differential signal (TMDS) serial link.

The method is accomplished by:

• having a transmitter and a receiver coupled by a TMDS serial link
• having the transmitter include an input for receiving video data and an input for receiving auxiliary data
• having the transmitter include outputs to the serial link channels, with the first output specifically linked to the serial link’s clock channel
• having the transmitter circuitry assert an output signal representing the video and auxiliary data to the outputs linked to the serial link channels
• and having the transmitter circuitry assert a clock signal representing both the video and at least one auxiliary clock signal to the first output linked to the serial link’s clock channel

Figure 6. Overview of the Serial Communications Link

Questions

1. Was the reference filed or published before September 12th, 2001? (True/False)
2. Does the reference describe a transmitter and a receiver transmitting digital video data over a serial link with at least one characteristic of a transition minimized differential signaling (TMDS) link?
3. Does the transmitter include an input for receiving video data and an input for receiving auxiliary data?
4. Does the transmitter contain outputs coupled to the channels of the serial link, with the first output coupled to a clock channel of the serial link?
5. Does the transmitter contain circuitry coupled to the inputs and outputs that is configured to assert an output signal representing the video and auxiliary data to the channels of the serial link?
6. Does the transmitter circuitry also assert a clock signal for both the video and at least one auxiliary clock signal to the first output connected to the clock channel of the serial link?

Glossary

• Transition minimized differential signaling (TMDS) is a method of transmitting high-speed serial data in a way as to reduce the electromagnetic interference over the link by minimizing the number of transitions in an output signal and using two signal lines (instead of signal to ground) to allow noise to be subtracted from the final output.