摘要:
A synchronous input to output protocol translator supporting multiple reference oscillator frequencies and fixed latency data computation and chip crossing circuits enables implementation of a method for delaying osc2 relative to osc1 in a configurable way to provide a constant, minimal Tptcc over a range of refosc frequencies between circuits for data transferred. It requires that the data transferred from a register R1 be sent over multiple wires via configurable delay circuitry for osc2, capture circuitry at the input to R2, and a circuit to transfer a synchronizing signal from a non-delayed clock domain to a delayed clock domain. Relative to osc1, osc2 is a delayed, synchronous clock.
摘要:
A memory system including a plurality of delay lines and a processor in communication with the delay lines. The delay lines are in communication with a bus attached to a memory device. The bus includes a plurality of wires and each of the delay lines corresponds to on of the plurality of wires. The processor receives a plurality of data bits and a data strobe via the wires on the bus. Each of the data bits includes data eye. The process also automatically calibrates the target data eye of each of the data bits and corresponds to the target data eye. In addition, the processor centers the data strobe over the target data eye.
摘要:
A memory built-in self test (MBIST) apparatus and method for testing dynamic random access memory (DRAM) arrays, the DRAM arrays in communication with a memory interface device that includes interface logic and mainline chip logic. The MBIST apparatus includes a finite state machine including a command generator and logic for incrementing data and addresses under test and a command scheduler in communication with the finite state machine. The command scheduler includes resource allocation logic for spacing commands to memory dynamically utilizing DRAM timing parameters. The MBIST apparatus also includes a test memory storing subtests of an MBIST test. Each of the subtests provides a full pass through a configured address range. The MBIST apparatus further includes a subtest pointer in communication with the test memory and the finite state machine. The finite state machine implements subtest sequencing of each of the subtests via the subtest pointer.
摘要:
A memory system including a first memory subsystem having a buffer device with a first port and a second port, one or more memory devices coupled to the buffer device via the second port, and a first two-on-one link for coupling to a memory controller for providing communication between the buffer device and the memory controller. The first two-on-one link is coupled to the first port of the buffer device. The first memory subsystem is configured to transfer data between at least one memory device of the one or more memory devices and the memory controller via the buffer device. The first two-on-one link includes up to two transceivers connected to a single link, with at least one of the up to two transceivers consisting of any one of two or more transmitters for transmitting signals or two or more receivers for receiving signals.
摘要:
A method and system for providing identification tags in a memory system having indeterminate data response times. An exemplary embodiment includes a memory controller in a memory system. The memory controller includes a mechanism for receiving data packets via an upstream channel, the data packets including upstream identification tags. The memory controller also includes a mechanism having instructions for facilitating determining if a received data packet is in response to a request from the memory controller. Input to the determining includes an upstream identification tag included in the received data packet. If the received data packet is determined to be in response to a request from the memory controller, then the received data packet is matched to the request, thereby allowing the memory controller to operate with indeterminate data response times.
摘要:
A method and system for providing indeterminate read data latency in a memory system. The method includes determining if a local data packet has been received. If a local data packet has been received, then the local data packet is stored into a buffer device. The method also includes determining if the buffer device contains a data packet and determining if an upstream driver for transmitting data packets to a memory controller via an upstream channel is idle. If the buffer contains a data packet and the upstream driver is idle, then the data packet is transmitted to the upstream driver. The method further includes determining if an upstream data packet has been received. The upstream data packet is in a frame format that includes a frame start indicator and an identification tag for use by the memory controller in associating the upstream data packet with its corresponding read instruction. If an upstream data packet has been received and the upstream driver is not idle, then the upstream data packet is stored into the buffer device. If an upstream data packet has been received and the buffer device does not contain a data packet and the upstream driver is idle, then the upstream data packet is transmitted to the upstream driver. If the upstream driver is not idle, then any data packets in progress are continued being transmitted to the upstream driver.
摘要:
A high reliability dual inline memory module with a fault tolerant address and command bus for use in a server. The memory module is a card approximately 151.35 mm or 5.97 inches long provided with about a plurality of contacts of which some are redundant, a plurality of DRAMs, a phase lock loop, a 2 or 32K bit serial EE PROM and a 28 bit and a 1 to 2 register having error correction code (ECC), parity checking, a multi-byte fault reporting circuitry for reading via an independent bus, and real time error lines for determining and reporting both correctable errors and uncorrectable error conditions coupled to the server's memory interface chip and memory controller or processor such that the memory controller sends address and command information to the register via address/command lines together with check bits for error correction purposes to the ECC/Parity register. By providing the module with a fault tolerant address and command bus fault-tolerance and self-healing aspects necessary for autonomic computing systems compatible with industry-standards is realized. The memory module corrects single bit errors on the command or address bus and permits continuous memory operation independent of the existence of these errors and can determine any double bit error condition. The redundant contacts on the module prevents what would otherwise be single points of failure.
摘要:
Circuitry for delaying a signal includes a phase-locked loop comprising one or more output nodes for outputting one or more output signals in response to a reference signal. A buffer is coupled to the output nodes of the phase-locked loop for receiving phase-locked loop output signals and outputs one or more buffered output signals. A multiplexing element receives the buffered output signals and a control signal and generates an operative buffered output signal in response to the control signal. A delay line receives a delay control input signal and the operative buffered output signal from the multiplexing element. The delay line outputs a delayed output signal in response to the delay control input signal.
摘要:
A memory subsystem for providing a bus speed multiplier. The memory subsystem includes one or more memory modules operating at a memory module data rate. The memory subsystem also includes a memory controller and one or more memory busses. The memory busses operate at four times the memory module data rate. The memory controller and the memory modules are interconnected by a packetized multi-transfer interface via the memory busses.
摘要:
A memory subsystem with a memory bus and a memory assembly. The memory bus includes multiple bitlanes. The memory assembly is in communication with the memory bus and includes instructions for receiving an error code correction (ECC) word in multiple packets via the memory bus. The ECC word includes data bits and ECC bits arranged into multiple multi-bit ECC symbols. Each of the ECC symbols is associated with one of the bitlanes on the memory bus. The memory assembly also includes instructions for utilizing one of the ECC symbols to perform error detection and correction for the bits in the ECC word received via the bitlane associated with the ECC symbol.