摘要:
A scheme for reducing jitter in high-speed digital communication by adaptively controlling the loop bandwidth of a receiver PLL to reduce the relative jitter between the recovered data and clock. The scheme uses phase pointer activity to represent the relative jitter. The phase pointer activity is measured and used to control the receiver PLL loop bandwidth. The receiver PLL loop bandwidth is repeatedly incremented or decremented by a step size based on the comparison between a newly measured activity value and the old activity value, until the phase pointer activity reaches a minimum. Because the PLL performance requirement of the transmitter can be relaxed, compatibility with legacy transmitters and multi-vendor transmitters is enhanced. Because tight control of fabrication process parameters of PLLs may be relaxed, the fabrication yield may also be improved.
摘要:
A method of transmitting data in a system including at least one data channel and a separate clock channel is disclosed. The method involves combining a clock signal to be transmitted on the clock channel with a data signal to generate a combined clock and data signal. In one embodiment, the data signal has been generated from data words using an encoding scheme that shifts an energy spectrum of the data signal away from an energy spectrum of the clock signal. In another embodiment, the clock signal has a plurality of pulses each having a front edge and a back edge, and the data signal is modulated onto the clock signal by moving at least one edge (i.e. front or back or both) of the plurality of pulses, thereby to create a combined clock and data signal.
摘要:
In preferred embodiments, an adaptive equalization circuit including at least two equalization filters (each for equalizing a signal transmitted over a multi-channel serial link) and control circuitry for generating an equalization control signal for use by all the filters. The control circuitry generates the control signal in response to an equalized signal produced by one of the filters, and asserts the control signal to all the filters. Preferably, one filter generates an equalized fixed pattern signal in response to a fixed pattern signal (e.g., a clock signal), each other filter equalizes a data signal, and the control circuitry generates the control signal in response to the equalized fixed pattern signal. In other embodiments, the invention is an adaptive equalization circuit including an equalization filter and circuitry for generating a control signal for the filter in response to a signal indicative of a predetermined fixed pattern, a receiver including an adaptive equalization circuit, a system including such a receiver, and a method for adaptive equalization of signals received over a multi-channel serial link.
摘要:
A cable including circuitry for asserting information to a user or external device and a system including such a cable. The cable can include conductors, a memory storing cable data, and circuitry configured to respond to a request received on at least one of the conductors by accessing at least some of the cable data and asserting the accessed data serially to at least one of the conductors (e.g., for transmission to an external device). Other aspects of the invention are methods for accessing cable data stored in a cable and optionally using the data (e.g., to implement equalization). The cable data can be indicative of all or some of cable type, grade, speed, length, and impedance, a date code, a frequency-dependent attenuation table, far-end crosstalk and EMI-related coefficients, common mode radiation, intra pair skew, and other information. The cable can include a radiation-emitting element and circuitry for generating driving signals for causing the radiation-emitting element to produce an appropriate color, brightness, and/or blinking pattern.
摘要:
A cable including circuitry for asserting information to a user or external device and a system including such a cable. The cable can include conductors, a memory storing cable data, and circuitry configured to respond to a request received on at least one of the conductors by accessing at least some of the cable data and asserting the accessed data serially to at least one of the conductors (e.g., for transmission to an external device). Other aspects of the invention are methods for accessing cable data stored in a cable and optionally using the data (e.g., to implement equalization). The cable data can be indicative of all or some of cable type, grade, speed, length, and impedance, a date code, a frequency-dependent attenuation table, far-end crosstalk and EMI-related coefficients, common mode radiation, intra pair skew, and other information. The cable can include a radiation-emitting element and circuitry for generating driving signals for causing the radiation-emitting element to produce an appropriate color, brightness, and/or blinking pattern.
摘要:
A cable including circuitry for asserting information to a user or external device and a system including such a cable. The cable can include conductors, a memory storing cable data, and circuitry configured to respond to a request received on at least one of the conductors by accessing at least some of the cable data and asserting the accessed data serially to at least one of the conductors (e.g., for transmission to an external device). Other aspects of the invention are methods for accessing cable data stored in a cable and optionally using the data (e.g., to implement equalization). The cable data can be indicative of all or some of cable type, grade, speed, length, and impedance, a date code, a frequency-dependent attenuation table, far-end crosstalk and EMI-related coefficients, common mode radiation, intra pair skew, and other information. The cable can include a radiation-emitting element and circuitry for generating driving signals for causing the radiation-emitting element to produce an appropriate color, brightness, and/or blinking pattern.
摘要:
A method, apparatus and system for pre-authenticating ports is disclosed. In one embodiment, an active port facilitating communication of media content between a transmitting device and a receiving device is identified, while the active port are associated with a first High-Definition Content Protection (HDCP) engine. Then, inactive ports that are in idle mode serving as backup ports to the active port are identified, while the inactive ports are associated with a second HDCP engine. Pre-authentication of each of the inactive ports is performed so the pre-authenticated inactive ports can subsequently replace the active port if a port switch is performed.
摘要:
Transmission of alternative content over standard device connectors. An embodiment of a method includes connecting a first device to a second device utilizing a standard connector, the connector including multiple pins, and detecting whether the second device is operating in a standard mode or an alternative mode. If the second device is operating in the alternative mode, then switching one or more pins of the standard connector for the alternative mode and transmitting or receiving signals for the alternative mode via the plurality of pins of the standard connector.
摘要:
Methods and apparatuses for using single-ended common mode signaling, additional data can be transferred in backward, forward, and/or both directions over an existing differential pair connection without adding extra wire.
摘要:
A method, apparatus and system for pre-authenticating ports is disclosed. In one embodiment, an active port facilitating communication of media content between a transmitting device and a receiving device is identified, while the active port are associated with a first High-Definition Content Protection (HDCP) engine. Then, inactive ports that are in idle mode serving as backup ports to the active port are identified, while the inactive ports are associated with a second HDCP engine. Pre-authentication of each of the inactive ports is performed so the pre-authenticated inactive ports can subsequently replace the active port if a port switch is performed.