Micron Technology Incorporated

Micron Electronics, Inc.

Round Rock Research, LLC

Douglas Alan Larson

Jeffrey J Cronin

Joseph M Jeddeloh

Paul A LaBerge

Jeffrey Jay Rooney

Jeffrey R Brown

Memory system controllers can include a switch and non-volatile memory control circuitry coupled to the switch. The non-volatile memory control circuitry can include a channel control circuit coupled to logical units. The channel control circuitry can be configured to relay an erase command to a first one of the logical units and relay a particular command from the switch to a second one of the logical units while the erase command is being executed on the first one of the plurality of logical units.

Apparatus including memory channel control circuit and related methods for relaying commands to logical units

A memory hub includes first and second link interfaces for coupling to respective data busses, a data path coupled to the first and second link interfaces and through which data is transferred between the first and second link interfaces, and further includes a write bypass circuit coupled to the data path to couple write data on the data path and temporarily store the write data to allow read data to be transferred through the data path while the write data is temporarily stored. A method for writing data to a memory location in a memory system is provided which includes accessing read data in the memory system, providing write data to the memory system, and coupling the write data to a register for temporary storage. The write data is recoupled to the memory bus and written to the memory location following provision of the read data.

Apparatus and method for data bypass for a bi-directional data bus in a hub-based memory sub-system

Memory system controllers can include hardware masters, first buffers, and a switch coupled to the hardware masters and to the first buffers. The switch can include second buffers and a buffer allocation management (BAM) circuit. The BAM circuit can include a buffer tag pool. The buffer tag pool can include tags, each identifying a respective first buffer or a respective second buffer. The BAM circuit can be configured to allocate a tag to a hardware master in response to an allocation request from the hardware masters. The BAM circuit can be configured to prioritize allocation of a tag identifying a second buffer over a tag identifying a first buffer.

Apparatus including buffer allocation management and related methods

A system with a processor in communication with a memory controller in communication with a plurality of memory devices wherein one of the plurality of memory devices is interposed between the memory controller and the remaining plurality of memory devices. By programming command delay in the memory controller, the command delay coordinates the execution of the command signal across all memory devices. The processor provides control signals to the memory controller that, in response, decodes the control signals and determines the mode of operation of one or more of the memory devices. The processor is also in communication with storage media and stores data in or retrieves data from the storage media.

System and method for controlling memory command delay

A daisy-chained memory topology wherein, in addition to the prediction of the timing of receipt of a response from a memory module (DIMM), the memory controller can effectively predict when a command sent by it will be executed by the addressee DIMM. By programming DIMM-specific command delay in the DIMM's command delay unit, the command delay balancing methodology according to the present disclosure 'normalizes' or 'synchronizes' the execution of the command signal across all DIMMs in the memory channel. By predicting command execution timing, the memory controller can efficiently control power profile of all the DRAM devices (or memory modules) on a daisy-chained memory channel. A separate DIMM-specific response delay unit in the DIMM is programmable to provide DIMM-specific delay compensation in the response path, further allowing the memory controller to accurately ascertain the timing of receipt of a response.

Memory command delay balancing in a daisy-chained memory topology

A methodology for a daisy-chained memory topology wherein, in addition to the prediction of the timing of receipt of a response from a memory module (DIMM), the memory controller can effectively predict when a command sent by it will be executed by the addressee DIMM. By programming DIMM-specific command delay in the DIMM's command delay unit, the command delay balancing methodology according to the present disclosure 'normalizes' or 'synchronizes' the execution of the command signal across all DIMMs in the memory channel. With such ability to predict command execution timing, the memory controller can efficiently control power profile of all the DRAM devices (or memory modules) on a daisy-chained memory channel. A separate DIMM-specific response delay unit in the DIMM may also be programmed to provide DIMM-specific delay compensation in the response path, further allowing the memory controller to accurately ascertain the timing of receipt of a response thereat, and, hence, to better manage further processing of the response.

One embodiment of the present invention provides an apparatus that selectively multiplexes a plurality of signal lines through an I/O pin on a semiconductor chip. This apparatus includes an I/O pin, for coupling a signal line within the semiconductor chip to a signal line outside of the semiconductor chip. A transmitting circuit is configured to selectively multiplex the plurality of signal lines onto the I/O pin. A receiving circuit is configured to receive multiplexed data from the I/O pin, and to reverse the multiplexing so that values originally from the multiplexed signal lines are separated into distinct signals in the receiving circuit. Note that the transmitting circuit and the receiving circuit are driven by a common clock signal. The apparatus additionally includes an initialization circuit that selectively configures the transmitting circuit and the receiving circuit to multiplex at least one of the plurality of signal lines through the I/O pin.

Apparatus for multiplexing signals through I/O pins

A memory hub receives downstream memory commands and processes each received downstream memory command to determine whether the memory command includes a write command directed to the memory hub. The memory hub operates in a first mode when the write command is directed to the hub to develop memory access signals adapted to be applied to memory devices. The memory hub operates in a second mode when the write command is not directed to the hub to provide the command's write data on a downstream output port adapted to be coupled to a downstream memory hub.

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Lakeville, MN, United States of America

Douglas Alan Larson