System and method for processing digital visual interface communication data signals and display data channel communication signals over a transmission line

A method for transmitting and receiving Digital Visual Interface (DVI) transition minimized differential signal (TMDS) communication data signals and Display Data Channel (DDC) communication signals over a transmission line, comprising:

• providing feedback loops at the inputs to a differential pair, the feedback loops independent of output signals generated by the differential pair;
• providing as input to the feedback ioop loop the DVI TMDS communication data signals at the received end of the transmission line;
• generating first and second differential input signals from the DVI TMDS communication data signals and the feedback loop;
• monitoring the DDC communication signal at the receive end of the transmission line;
• and
• injecting a boost current at the receive end of the transmission line during a portion of the positive transition in the DDC communication signal;
• wherein the step of monitoring the DDC communication signal at a receive end of the transmission line comprises:
• generating an injection activation signal when the DDC communication signal exceeds a first reference value;
• and
• eliminating the injection activation signal when the DDC communication signal exceeds a second reference value;
• wherein the presence of the injection activation signal causes injection of the boost current at the receive end of the transmission line
• wherein the step of monitoring the DDC communication signal at a receive end of the transmission line further comprising:
• generating a first output by a first comparator having a first input and a second input, the second input coupled to the receive end of the transmission line, the first output being high when the second input exceeds the first input and the first output being low when the second input does not exceed the first input;
• generating a second output by a second comparator having a third input and a fourth input, the fourth input coupled to the receive end of the transmission line, the second output being high when the fourth input exceeds the third input, and the second output being low when the fourth input does not exceed the third input;
• receiving the first output by a latch as a reset input and receiving the second output by the latch as a set input;
• receiving the output of the latch by a nand gate and receiving the inverted second output by the nand gate;
• and
• injecting the boost current when the output of the nand gate is high.

A system for transmitting and receiving Digital Visual Interface (DVI) transition minimized differential signal (TMDS) communication data signals and Display Data Channel (DDC) communication signals over a transmission line, comprising:

• means for providing feedback loops at the inputs to a differential pair, the feedback loops independent of output signals generated by the differential pair;
• means for providing as input to the feedback loop the DVI TMDS communication data signals at the received end of the transmission line;
• means for generating first and second differential input signals from the DVI TMDS communication data signals and the feedback loop;
• means for monitoring the DDC communication signal at the receive end of the transmission line;
• and
• means for injecting a boost current at the receive end of the transmission line during a portion of the positive transition in the DDC communication signal
• wherein the means for monitoring the DDC communication signal at the receive end of the transmission line comprises:
• means for generating an injection activation signal when the DDC communication signal exceeds a first reference value;
• and
• means for eliminating the injection activation signal when the DDC communication signal exceeds a second reference value;
• wherein the presence of the injection activation signal causes injection of the boost current at the receive end of the transmission line,
• the open-loop equalizer circuit providing either proportional or disproportional equalization to the TMDS communication data signal, wherein proportional equalization provides a frequency dependent gain that is at or about the inverse of a frequency dependent attenuation caused by the transmission line, the DVI communication data signal being proportionally equalized, and if the open-loop equalizer wherein disproportionate equalization provides a frequency dependent gain that is greater than the inverse of a frequency dependent attenuation caused by the transmission line, then the DVI communication data signal being proportionately equalized .