A wireline communications system is described. The wireline communications system includes a printed circuit board (PCB). The wireline communications system also includes a system on chip (SoC) die on the PCB. The wireline communications system further includes an external memory device coupled to a memory interface of the SoC die. The external memory device is coupled to the memory interface of the SoC die through a PCB trace. A length of the PCB trace is configured according to an operating speed of the memory interface.

Devices and techniques are disclosed herein for determining, using a host device, a timing relationship between a data strobe signal, such as from an embedded MultiMediaCard (eMMC) device, and an internal clock signal. The host device can control a delay circuit using the determined timing relationship, such as to align received read data for sampling, or to determine or adjust a delay value of the delay circuit.

The system on a chip includes at least a first digital domain configured to be reinitialized by a first reinitialization signal, a second digital domain and an interface circuit. The interface circuit includes a starting register in the first digital domain, a destination register in the second digital domain and a synchronization circuit in the first digital domain. The interface circuit is configured to transfer data from the starting register to the destination register upon command of a control signal transmitted by the synchronization circuit. The starting register and the synchronization circuit are configured to not be reinitialized by the first reinitialization signal.

An integrated circuit device outputs a sequence of differently delayed calibration data timing signals to a DRAM component via a data-signal timing line as part of a timing calibration operation and then stores a delay value, based on at least one of the calibration data timing signals, that compensates for a difference in signal propagation times over the data-signal timing line and a command/address-signal timing line. After the timing calibration operation, the integrated circuit device outputs write data to the DRAM component and outputs a write data timing signal, delayed according to the delay value, to via the data-signal timing line to time reception of the first write data within the DRAM.

Techniques for command bus training to a memory device includes triggering a memory device to enter a first or a second command bus training mode, outputting a command/address (CA) pattern via a command bus and compressing a sampled CA pattern returned from the memory device based on whether the memory device was triggered to be in the first or the second command bus training mode.

An electronic system is provided. A memory device includes a plurality of bank groups. A controller is coupled to the memory device and includes a request queue. The request queue is configured to store a plurality of requests. When the requests correspond to the different bank groups, the controller is configured to access data of the memory device according to a plurality of long burst commands corresponding to the requests. When the requests correspond to the same bank group, the controller is configured to access the data of the memory device according to a plurality of short burst commands corresponding to the requests. The short burst commands correspond to a short burst length, and the long burst commands correspond to a long burst length. The long burst length is twice the short burst length. The memory device is a low-power double data rate synchronous dynamic random access memory.

A method of operating a memory controller is disclosed. The method includes transmitting data signals to a memory device over each one of at least two parallel data links. A timing signal is sent to the memory device on a first dedicated link. The timing signal has a fixed phase relationship with the data signals. A data strobe signal is driven to the memory device on a second dedicated link. Phase information is received from the memory device. The phase information being generated internal to the memory device and based on a comparison between the timing signal and a version of the data strobe signal internally distributed within the memory device. A phase of the data strobe signal is adjusted relative to the timing signal based on the received phase information.

A computer architecture provides both a parallel memory bus and serial memory bus between a processor system and memory. Latency-tolerant memory access requests are steered to the serial memory bus which operates to increase the available memory bus bandwidth on the parallel memory. The invention also provides integrated circuit computer memory suitable for this application.

A memory system of a high-speed operation can be realized by reducing an influence of reflection signals etc. caused by branching and impedance mismatching in various wirings between a memory controller and a memory module, and an influence due to transmission delays of data, command/address, and clocks in the memory module. To this end, a memory system comprises a memory controller and a memory module mounted with DRAMs. A buffer is mounted on the memory module. The buffer and the memory controller are connected to each other via data wiring, command/address wiring, and clock wiring. The DRAMs and the buffer on the memory module are connected to each other via internal data wiring, internal command/address wiring, and internal cock wiring. The data wiring, the command/address wiring, and the clock wiring may be connected to buffers of other memory modules in cascade. Between the DRAMs and the buffer on the memory module, high-speed data transmission is implemented using data phase signals synchronous with clocks.

A data bus subscriber connected to a local bus, particularly a ring bus. The data bus subscriber has a status signal input for receiving a first status signal value from a downstream data bus subscriber or a terminator, a status signal output for providing a second status signal value to an upstream data bus subscriber or to a local bus master, wherein the data bus subscriber is adapted to provide the second status signal value based on a logical link of a communication readiness of the data bus subscriber and the first status signal value. The invention further relates to a corresponding method and a local bus.