Abstract: Embodiments of the present disclosure provide methods for using a compliance model to determine compatibility of a channel with a bus's chip I/O circuitry at its ends. The method includes identifying at least one design criteria and obtaining boundary sets of frequency domain parameters for compliant signal channels known to achieve the design criteria. In certain embodiments, the boundary sets may be derived using a genetic algorithm. The method further includes verifying whether a particular signal channel is compliant by comparing values of frequency domain parameters for the particular channel to one or more of the boundary sets of frequency domain parameters for the known compliant channels.

Abstract: A digital data communications mechanism includes multiple parallel lines, in which components of one or more lines are temporarily powered down to save power. Preferably, both the transmitter and receiver contain respective generators generating identical pre-determined pseudo-random bit streams, which are initially synchronized and which remain powered up when the line is temporarily powered down. Upon re-powering the line, the transmitter transmits the locally generated bit stream, and the receiver compares the received bit stream with its internally generated bit stream to determine an amount of shift required for re-synchronization.

Abstract: Mechanisms, in a data processing system comprising an input/output subsystem implementing an industry standard optical bus, for handling a failure of an optical channel in an optical bus are provided. The mechanisms detect, by failure detection logic of the input/output (I/O) subsystem, failure of an optical channel of the optical bus. The mechanisms send, by a controller of the I/O subsystem, a control signal to channel routing logic of the I/O subsystem to control a routing of data signals between active bus lanes of the data processing system and optical channels of the optical bus in response to detecting the failure of the optical channel. The mechanisms control, by the channel routing logic, routing of data signals between the active bus lanes and the optical channels so as to remove the failed optical channel from further use and use a spare optical channel instead of the failed optical channel.

Abstract: Embodiments of the present disclosure provide methods for testing channel compliance. The method generally includes identifying at least one design criteria and determining boundary sets of frequency domain parameters for compliant signal channels known to achieve the design criteria. The boundary sets may be used for verifying whether a particular signal channel is compliant by comparing values of frequency domain parameters for the particular channel to one or more of the boundary sets of frequency domain parameters for the known compliant channels.

Abstract: A calibratable communications link includes multiple parallel lines. Calibration is performed at dynamically variable and/or interruptible intervals determined by an automated mechanism. Calibration is preferably initiated responsive to a command generated by an executable software process, which initiates calibration responsive to detection of a probable impending need as indicated by, e.g., temperature change, calibrated parameter drift, error rate, etc. Calibration is also preferably initiated according to probable minimal disruption of device function, as indicated by low activity level. Furthermore, in one aspect calibration may be temporarily suspended to transmit data and then resumed.

Abstract: Embodiments of the present disclosure provide apparatus for testing channel compliance. The apparatus generally performs operations that includes identifying at least one design criteria and determining boundary sets of frequency domain parameters for compliant signal channels known to achieve the design criteria. The boundary sets may be used for verifying whether a particular signal channel is compliant by comparing values of frequency domain parameters for the particular channel to one or more of the boundary sets of frequency domain parameters for the known compliant channels.

Abstract: A digital data communications mechanism includes multiple parallel lines, in which components of one or more lines are temporarily powered down to save power. Preferably, both the transmitter and receiver contain respective generators generating identical pre-determined pseudo-random bit streams, which are initially synchronized and which remain powered up when the line is temporarily powered down. Upon re-powering the line, the transmitter transmits the locally generated bit stream, and the receiver compares the received bit stream with its internally generated bit stream to determine an amount of shift required for re-synchronization.

Abstract: Embodiments of the present disclosure provide apparatus for using a compliance model to determine compatibility of a channel with a bus's chip I/O circuitry at its ends. The apparatus includes at least one processor and a memory coupled to the at least one processor. The processor is configured to: identify at least one design criteria; obtain boundary sets of frequency domain parameters for compliant signal channels known to achieve the design criteria; and verify whether a particular signal channel is compliant by comparing values of frequency domain parameters for the particular channel to one or more of the boundary sets of frequency domain parameters for the known compliant channels.

Abstract: Embodiments disclosed herein generally relate to techniques for routing data through one or more cascaded memory modules. Each memory module can include a plurality of data buffers. Each data buffer includes a plurality of ports for routing data to and/or from other memory modules. In one embodiment, the data buffer is configured to route write data to DRAM devices on a first memory module or route write data to a data buffer of at least one downstream memory module. The data buffer is also configured to receive read data from a DRAM device of the first memory module or receive read data from a downstream memory module.

Abstract: Embodiments of the present disclosure provide an apparatus for synchronizing a common reference clock over optics. For example, a reference clock from a host device may be frequency adjusted based on a pass-band of an optical link, decoded, and converted into an optical signal, and transferred to a controller of a target device via one or more optical cables. The controller may be used to recover the reference clock using the optical signal, which may be used as a common-reference clock for communications between the host and target devices.

Abstract: Computer program product and apparatus for repairing a communication link failure. In certain embodiments, the apparatus generally includes a controller configured to initialize the communication link for communication with another apparatus using an initial number of channels of a plurality of channels. The apparatus may also include a plurality of multiplexers configured to selectively couple a plurality of communication lanes with the plurality of channels of the communication link. In certain embodiments, during an initial state, a first lane of the plurality of lanes may be coupled with a first channel of the plurality of channels, and the plurality of channels may include a spare channel. The controller may determine whether at least one channel of the plurality of channels is experiencing a failure and control at least one of the multiplexers such that the failed channel is replaced by another channel of the plurality of channels by using the spare channel.

Abstract: Embodiments described herein include a quadrature phase corrector (QPC) which includes multiple differential amplifies for correcting the phase of one or more clock signals. In one embodiment, the differential amplifiers are arranged in an input stage, cross-coupled stage, and ring stage. The input stage receives and buffers the input clock signal (or signals). The cross-coupled stage includes one or more latches that force one clock signal high and another low which causes the QPC to oscillate. The ring stage outputs four clock signals with adjusted phases relative to the input clock signals. In one example, the ring stage outputs a quadrature clock signal that includes four clock signals phase shifted by 90 degrees.

Abstract: Method for repairing a communication link failure. In certain embodiments, the method generally includes communicating with another apparatus using an initial number of channels of a plurality of channels of a communication link; selectively coupling a plurality of communication lanes with the plurality of channels of the communication link, wherein, during an initial state, a first lane of the plurality of lanes is coupled with a first channel of the plurality of channels, and wherein the plurality of channels comprises a spare channel; determining whether at least one channel of the plurality of channels is experiencing a failure; and controlling at least one of the multiplexers such that the failed channel is replaced by another channel of the plurality of channels by using the spare channel.

Abstract: Embodiments of the present disclosure provide an apparatus for synchronizing a common reference clock over optics. For example, a reference clock from a host device may be frequency adjusted based on a pass-band of an optical link, decoded, and converted into an optical signal, and transferred to a controller of a target device via one or more optical cables. The controller may be used to recover the reference clock using the optical signal, which may be used as a common-reference clock for communications between the host and target devices.

Abstract: Mechanisms, in a data processing system comprising an input/output subsystem implementing an industry standard optical bus, for handling a failure of an optical channel in an optical bus are provided. The mechanisms detect, by failure detection logic of the input/output (I/O) subsystem, failure of an optical channel of the optical bus. The mechanisms send, by a controller of the I/O subsystem, a control signal to channel routing logic of the I/O subsystem to control a routing of data signals between active bus lanes of the data processing system and optical channels of the optical bus in response to detecting the failure of the optical channel. The mechanisms control, by the channel routing logic, routing of data signals between the active bus lanes and the optical channels so as to remove the failed optical channel from further use and use a spare optical channel instead of the failed optical channel.

Abstract: A memory system is deigned for impedance matching using a network of resistors that are tuned to reduce reflections on a shared bus. Any deviation from the matched state causes a mismatch and results in reflections on the bus. Overall signal reflections are reduced by balancing the back reflections occurring at a connector junction coupled to a pair of resistors and the back reflections occurring at the input of the DIMMs. This balance or tradeoff is achieved by changing the resistance value of the resistor pair to reduce the overall back reflections in the memory system.

Abstract: Embodiments of the present disclosure provide apparatus for using a compliance model to determine compatibility of a channel with a bus's chip I/O circuitry at its ends. The apparatus includes at least one processor and a memory coupled to the at least one processor. The processor is configured to: identify at least one design criteria; obtain boundary sets of frequency domain parameters for compliant signal channels known to achieve the design criteria; and verify whether a particular signal channel is compliant by comparing values of frequency domain parameters for the particular channel to one or more of the boundary sets of frequency domain parameters for the known compliant channels.

Abstract: Embodiments of the present disclosure provide apparatus for testing channel compliance. The apparatus generally performs operations that includes identifying at least one design criteria and determining boundary sets of frequency domain parameters for compliant signal channels known to achieve the design criteria. The boundary sets may be used for verifying whether a particular signal channel is compliant by comparing values of frequency domain parameters for the particular channel to one or more of the boundary sets of frequency domain parameters for the known compliant channels.

Abstract: Embodiments of the present disclosure provide methods for using a compliance model to determine compatibility of a channel with a bus's chip I/O circuitry at its ends. The method includes identifying at least one design criteria and obtaining boundary sets of frequency domain parameters for compliant signal channels known to achieve the design criteria. In certain embodiments, the boundary sets may be derived using a genetic algorithm. The method further includes verifying whether a particular signal channel is compliant by comparing values of frequency domain parameters for the particular channel to one or more of the boundary sets of frequency domain parameters for the known compliant channels.

Abstract: Embodiments of the present disclosure provide methods for testing channel compliance. The method generally includes identifying at least one design criteria and determining boundary sets of frequency domain parameters for compliant signal channels known to achieve the design criteria. The boundary sets may be used for verifying whether a particular signal channel is compliant by comparing values of frequency domain parameters for the particular channel to one or more of the boundary sets of frequency domain parameters for the known compliant channels.