Abstract: A physical memory interface (Phy) and method of operating is disclosed. The Phy interface includes command and status registers (CSRs) configured to receive a first power context and second power context. Selection circuitry is configured to switch between the first and second power contexts. A plurality of adjustable delay elements are provided, each having a delay time responsive to the selected power context. A first set of CSRs configured may store the first power context and a second set of CSRs configured may store the second power context. The Phy interface may also include a plurality of drivers each having a selectable drive strength responsive to the selected power context. The Phy interface may also include a plurality of receivers each having a selectable termination impedance responsive to the selected power context. Switching between power contexts may result in adjusting of the delay elements, drive strength and/or termination impedance of one or more drivers/receivers.

Abstract: Various method and apparatus embodiments for training a delay for enabling a data strobe signal in a memory subsystem are disclosed. In one embodiment, a system includes a memory controller configured to receive a data strobe signal. The memory controller includes a training circuit. The training circuit includes a first storage circuit coupled to receive the data strobe signal on a data input and an enable signal on a clock input, and a training unit configured to, based on an output signal received from the first flip-flop, adjust a phase of the enable signal until an assertion of the enable signal coincides with a preamble indication in the data strobe signal.

Abstract: Various method and apparatus embodiments for training a delay for enabling a data strobe signal in a memory subsystem are disclosed. In one embodiment, a system includes a memory controller configured to receive a data strobe signal. The memory controller includes a training circuit. The training circuit includes a first storage circuit coupled to receive the data strobe signal on a data input and an enable signal on a clock input, and a training unit configured to, based on an output signal received from the first flip-flop, adjust a phase of the enable signal until an assertion of the enable signal coincides with a preamble indication in the data strobe signal.

Abstract: A first plurality of clock signals including a first clock signal and a second clock signal is received, the first and second clock signal out of phase with each other. A second plurality of clock signals comprising a third clock signal and a fourth clock signal is received, the third and fourth clock signals out of phase with each other. A plurality of enable signals are received. A fifth clock signal is determined based on the first plurality of clock signals and the plurality of enable signals. A sixth clock signal is determined based on the second plurality of clock signals and the plurality of enable signals. A seventh clock signal is determined based on the fifth clock signal and the sixth clock signal.

Abstract: A physical memory interface (Phy) and method of operating is disclosed. The Phy interface includes command and status registers (CSRs) configured to receive a first power context and second power context. Selection circuitry is configured to switch between the first and second power contexts. A plurality of adjustable delay elements are provided, each having a delay time responsive to the selected power context. A first set of CSRs configured may store the first power context and a second set of CSRs configured may store the second power context. The Phy interface may also include a plurality of drivers each having a selectable drive strength responsive to the selected power context. The Phy interface may also include a plurality of receivers each having a selectable termination impedance responsive to the selected power context. Switching between power contexts may result in adjusting of the delay elements, drive strength and/or termination impedance of one or more drivers/receivers.

Abstract: A physical memory interface (Phy) and method of operating is disclosed. The Phy interface includes command and status registers (CSRs) configured to receive a first power context and second power context. Selection circuitry is configured to switch between the first and second power contexts. A plurality of adjustable delay elements are provided, each having a delay time responsive to the selected power context. A first set of CSRs configured may store the first power context and a second set of CSRs configured may store the second power context. The Phy interface may also include a plurality of drivers each having a selectable drive strength responsive to the selected power context. The Phy interface may also include a plurality of receivers each having a selectable termination impedance responsive to the selected power context. Switching between power contexts may result in adjusting of the delay elements, drive strength and/or termination impedance of one or more drivers/receivers.

Abstract: A first plurality of clock signals including a first clock signal and a second clock signal is received, the first and second clock signal out of phase with each other. A second plurality of clock signals comprising a third clock signal and a fourth clock signal is received, the third and fourth clock signals out of phase with each other. A plurality of enable signals are received. A fifth clock signal is determined based on the first plurality of clock signals and the plurality of enable signals. A sixth clock signal is determined based on the second plurality of clock signals and the plurality of enable signals. A seventh clock signal is determined based on the fifth clock signal and the sixth clock signal.

Abstract: A system including a host coupled to a serially connected chain of memory modules. In one embodiment, each of the memory modules includes a memory control hub for controlling access to a plurality of memory chips on the memory module. The memory modules are coupled serially in a chain to the host via a plurality of memory links. Each memory link may include an uplink for conveying transactions toward the host and a downlink for conveying transactions originating at the host to a next memory module in the chain. The uplink and the downlink may convey transactions using packets that include control and configuration packets and memory access packets. The memory control hub may convey a transaction received on a first downlink of a first memory link on a second downlink of a second memory link independent of decoding the transaction.

Abstract: An integrated device (e.g., an integrated PCI bridge device) buffers received PCI bus strobe signals and distributes strobe signals for PCI receive data relative to the PCI data lines, enabling all PCI receive data to be latched using locally-generated PCI strobe signals generated based on the same PCI bus strobe signals. In addition, data line latch modules having primary and secondary flip-flops enable the PCI receive data to be held for an entire clock cycle, optimizing conversion between a PCI clock domain and a local clock domain of the PCI bridge device. A transmission circuit also can be configured to transmit data according to either double data rate (DDR) mode or quad data rate (QDR) mode in an efficient manner.

Abstract: A method is provided for utilizing four error correcting code (ECC) pin connections of a PCI/PCI-X bus for one of Grant (GNT) and Request (REQ) pin connections. The method determines a mode of the PCI bus to be PCI-X Mode 1, PCI-X Mode 2, or PCI. If the determined mode is PCI-X Mode 2, the four ECC pin connections are used as ECC pin connections, and if the determined mode is PCI or PCI-X Mode 1, each of the four ECC pin connections is used as a GNT pin connection or a REQ pin connection.

Abstract: A phase alignment circuit having a phase selection circuit, a synchronizer, and a counter form a feedback loop for aligning a local clock signal with a received reference clock of a synchronous communications system. The phase selection circuit is configured for outputting the local clock signal as a phase-adjusted local clock having a selected phase based on a phase selection value specified by the counter. The synchronizer is configured for digitally sampling the received reference clock relative to the phase-adjusted local clock, and outputting a digital phase bit identifying whether the phase-adjusted local clock has a later phase relative to the received reference clock. The counter selectively increments or decrements a counted value based on the digital phase bit, and outputs to the phase selection circuit a prescribed number of most significant bits from the counted value as the phase selection value.

Abstract: An integrated device (e.g., an integrated PCI bridge device), having configuration registers for storing configuration values, device logic for generating internal state values based on the configuration values, and a JTAG interface configured for receiving a serial input stream and outputting a serial output stream, further includes write logic and debug read logic. The write logic is configured for writing selected portions of the serial input stream into respective selected ones of the configuration registers, based on a detected input indicating a JTAG-based override. The debug read logic is configured, in response to a detected debug mode, for outputting selected internal state values for the serial output stream, based on selection values from the serial input stream and having been stored in a prescribed at least one of the selected configuration registers.

Abstract: A method is provided for selectively using a PCIXCAP pin input to detect PCI/PCI-X bus mode or as DC pin input. The method provides a PCI/PCI-X device having PCIXCAP pin input, and a circuit having a plurality of voltage level detection structures and an output corresponding to each voltage level detection structure. Each output is received by a first logic to detect the PCI bus mode of a device defining a first, PCIXCAP mode for the pin input. The method ensures that one of the plurality of voltage level detection structures may be used as a DC signal logic to provide a DC output signal to a second logic. A mode of the PCIXCAP pin input is selected so as to provide the DC output signal under conditions where the PCI/PCI-X bus mode is not being detected. In an embodiment, the DC output signal is used in as a PCI Hot-Plug interface signal.

Abstract: Duplicate PCI bridge devices are configured for synchronous initializations based on shared initialization signals. A first of the PCI bridge devices is configured to rely on bus arbitration performed by the second PCI bridge device. The first PCI bridge device also is configured for modifying an address of a data transaction received via a PCI bus, and forwarding the data transaction with the modified address to the second PCI bridge device via a link distinct from the PCI bus.

Abstract: A host is coupled to a serially connected chain of memory modules. In one embodiment, a method for initializing the host and each of memory modules includes the host transmitting a first synchronization pattern and a second synchronization pattern downstream in response to a reset condition. The method also includes each memory module in the serially connected chain of memory modules receiving and forwarding the first and the second synchronization pattern. Each memory module receives and forwards the first and the second synchronization pattern. Further, the method includes the host transmitting a plurality of NOP packets downstream in response to transmitting the second synchronization pattern. Lastly, the method includes a portion of the memory modules injecting and transmitting NOP packets upstream in response to receiving the second synchronization pattern from downstream.

Abstract: A system including a host coupled to a serially connected chain of memory modules. In one embodiment, each of the memory modules includes a memory control hub for controlling access to a plurality of memory chips on the memory module. The memory modules are coupled serially in a chain to the host via a plurality of memory links. Each memory link may include an uplink for conveying transactions toward the host and a downlink for conveying transactions originating at the host to a next memory module in the chain. The uplink and the downlink may convey transactions using packets that include control and configuration packets and memory access packets. The memory control hub may convey a transaction received on a first downlink of a first memory link on a second downlink of a second memory link independent of decoding the transaction.

Abstract: A method and system for handling a branch instruction which requires branching from a current instruction of a first instruction sequence to the first instruction of a second instruction sequence. The branch instruction is fetched and the next instruction of the first sequence is fetched while the branch instruction is displacement formatted. The first instruction of the second sequence is fetched while such next instruction is displacement formatted and the branch instruction is executed. The second instruction of the second sequence is fetched while the first instruction is displacement formatted, but the next instruction of the first sequence is not executed so that an execution wait occurs. The third instruction of the second sequence is then fetched while the second instruction is displacement formatted and the first instruction is executed.

Abstract: An improved liquid handling device used for transferring a selected quantity of liquid from one receptacle to another. The device includes a meniscus tracking feature which minimizes mixing in a liquid sample and contact between the sample and a sample-handling pipette during a liquid-transfer operation. Further included is a volume-correcting feature for improving the accuracy of volume withdrawn into or dispensed from the pipette during a liquid handling operation.