Communication system, transmitter, receiver, communication method, program, and communication cable

A receiver for receiving, using a first differential signal, pixel data of an uncompressed image of one screen unidirectionally transmitted from a transmitter during an effective video period representing a period from one vertical synchronization signal to the next vertical synchronization signal excluding horizontal blanking intervals and a vertical blanking interval, the receiver comprising:

• decoding means for receiving a second differential signal formed from a first constituent signal transmitted from the transmitter via a first signal line and a second constituent signal transmitted from the transmitter via a second signal line and decoding the second differential signal to original data;
• first selecting means for selecting one of the first constituent signal and a first reception signal related to a control operation and transmitted from the transmitter via the first signal line;
• first control means for performing control so that, when the first reception signal is received, the first reception signal is selected and received by the first selecting means and, when the second differential signal is received, the first constituent signal is selected by the first selecting means and is received by the decoding means;
• and
• converting means for converting transmission data different from the pixel data into a third differential signal formed from a third constituent signal and a fourth constituent signal and transmitting the third differential signal to the transmitter,
• wherein the transmitter prepares an eHDMI protocol tag and an Extended Display Identification Data information tag upon receipt of EDID data from the receiver and sends the eHDMI protocol tag and EDID information tag to the receiver, and
• wherein the receiver compares the content of the EDID information tag with the content of the EDID data of the receiver, and when the content of EDID information tag matches the content of the EDID data of the receiver the receiver determines that the transmitter is an enhanced High Definition Multimedia Interface device connected to the receiver using an eHDMI cable.

A communication method for use in a receiver, the receiver receiving, using a first differential signal, pixel data of an uncompressed image of one screen unidirectionally transmitted from a transmitter during an effective video period representing a period from one vertical synchronization signal to the next vertical synchronization signal excluding horizontal blanking intervals and a vertical blanking interval, the receiver including decoding means for receiving a second differential signal formed from a first constituent signal transmitted from the transmitter via a first signal line and a second constituent signal transmitted from the transmitter via a second signal line and decoding the second differential signal to original data, selecting means for selecting one of the first constituent signal and a reception signal related to a control operation and transmitted from the transmitter via the first signal line, and converting means for converting transmission data different from the pixel data into a third differential signal and transmitting the third differential signal to the transmitter, the method comprising the step of:

• performing control so that, when the reception signal is received, the reception signal is selected by the selecting means and is received and, when the second differential signal is received, the first constituent signal is selected by the selecting means and is received by the decoding means,
• wherein the transmitter prepares an eHDMI protocol tag and an Extended Display Identification Data information tag upon receipt of EDID data from the receiver and sends the eHDMI protocol tag and EDID information tag to the receiver, and
• wherein the receiver compares the content of the EDID information tag with the content of the EDID data of the receiver, and when the content of EDID information tag matches the content of the EDID data of the receiver the receiver determines that the transmitter is an enhanced High Definition Multimedia Interface device connected to the receiver using an eHDMI cable.

A communication cable for connecting between a transmitter and a receiver, the transmitter unidirectionally transmitting, using a first differential signal, pixel data of an uncompressed image of one screen to the receiver during an effective video period representing a period from one vertical synchronization signal to the next vertical synchronization signal excluding horizontal blanking intervals and a vertical blanking interval, the transmitter including first converting means for converting transmission data different from the pixel data into a second differential signal formed from a first constituent signal and a second constituent signal, transmitting the first constituent signal to the receiver via a first signal line, and outputting the second constituent signal, first selecting means for selecting one of a transmission signal related to a control operation and the second constituent signal output from the first converting means and transmitting the selected signal to the receiver via a second signal line, first control means for performing control so that, when the transmission signal is transmitted to the receiver, the transmission signal is selected by the first selecting means and, when the second differential signal is transmitted to the receiver, the second constituent signal is selected by the first selecting means, and first decoding means for receiving a third differential signal transmitted from the receiver and decoding the third differential signal into original data, the receiver receiving the first differential signal transmitted from the transmitter, the receiver including second converting means for converting transmission data different from the pixel data into the third differential signal and transmitting the third differential signal to the transmitter, second decoding means for receiving the second differential signal transmitted from the transmitter and decoding the second differential signal to original data, second selecting means for selecting one of the second constituent signal and the transmission signal, and second control means for performing control so that, when the transmission signal is received, the transmission signal is selected by the second selecting means and is received and, when the second differential signal is received, the second constituent signal is selected by the second selecting means and is received by

• the second decoding means, the communication cable comprising:
• the first signal line;
• and the second signal line;
• wherein the first signal line and the second signal line are twisted together so as to form a twisted wire differential pairL
• wherein the transmitter prepares an eHDMI protocol tag and an Extended Display Identification Data information tag upon receipt of EDID data from the receiver and sends the eHDMI protocol tag and EDID information tag to the receiver, and
• wherein the receiver compares the content of the EDID information tag with the content of the EDID data of the receiver, and when the content of EDID information tag matches the content of the EDID data of the receiver the receiver determines that the transmitter is an enhanced High Definition Multimedia Interface (eHDMI) device connected to the receiver using an eHDMI cable.