Hewlett-packard Development Company, L.p.

Compaq Information Technologies Group, L.p.

Hewlett-packard Company

John MacLaren

John Edward Larson

Robert A Lester

Gary J Piccirillo

Jerome J Johnson

Christian H Post

Jeffery L Galloway

Eric Rose

Tim W Majni

Benjamin H Clark

Siamak Tavallaei

Anisha Anand

Paul A Santeler

Patrick Lee Ferguson

Ho M Lai

George D Megason

Brett D Roscoe

Jeffrey S Autor

Dan Fink

Bret D Roscoe

Sompong Paul Olarig

Thomas J Bonola

Kenneth A Jansen

William J Walker

Jerry Johnson

A memory subsystem may be usable in an electronic system. The memory subsystem may comprise a memory controller and a plurality of memory modules coupled to the memory controller. The memory module may be isolated wherein transactions that target the isolated memory module can complete without loss of data and without accessing the isolated memory module, and while isolated, the memory module can be tested.

Memory testing

A computer system includes a plurality of memory modules that contain semiconductor memory, such as DIMMs. The system includes a host/data controller that utilizes an XOR engine to store data and parity information in a striped fashion on the plurality of memory modules to create a redundant array of industry standard DIMMs (RAID). The host/data controller also interleaves data on a plurality of channels associated with each of the plurality of memory modules. The system implements error interrupt control, ECC error reporting, cartridge error power down procedures in response to command errors, storage of error information in unused segments of each DIMM, hot-pug procedure indicator and remote tagging capabilities of memory cartridges and DIMMs.

Error indication in a raid memory system

A computer system includes a plurality of memory modules that contain semiconductor memory, such as DIMMs. The system includes a host/data controller that utilizes an XOR engine to store data and parity information in a striped fashion on the plurality of memory modules to create a redundant array of industry standard DIMMs (RAID). The host/data controller also interleaves data on a plurality of channels associated with each of the plurality of memory modules. To optimize memory bandwidth and reduce memory latency, various techniques are implemented in the present RAID system. Present techniques include providing dual memory arbiters, sorting read cycles by chip select or bank address, providing programmable upper and lower boundary registers to facilitate programmable memory mapping, and striping and interleaving memory data to provide a burst length of one.

Memory latency and bandwidth optimizations

A processor-based device having a plurality of memory cartridges secured within a chassis by a lever system. The processor-based device comprises an indication system to indicate memory system operating conditions. Each memory cartridge has a protective assembly to protect memory elements within the memory cartridge when the memory cartridge is removed from the processor-based device. The processor-based device is operable such that at least one memory cartridge may be removed from the processor-based device without affecting operation of the processor-based device.

Removable memory cartridge system for use with a server or other processor-based device

A technique for identifying the location of electrical components, such as memory cartridges which have been disposed on a substrate. More specifically, a connector configured to be coupled to a first substrate and configured to receive a second substrate, wherein the connector includes an identification device uniquely configured to provide location information and to electrically couple a plurality of location identification signals to the second substrate, the electrical signals being received from traces on the first substrate.

Technique for identifying multiple circuit components

A computer system includes a plurality of memory modules that contain semiconductor memory, such as DIMMs. The system includes a host/data controller that utilizes an XOR engine to store data and parity information in a striped fashion on the plurality of memory modules to create a redundant array of industry standard DIMMs (RAID). The host/data controller also interleaves data on a plurality of channels associated with each of the plurality of memory modules.

Method for supporting multi-level striping of non-homogeneous memory to maximize concurrency

The control logic for a hot-pluggable memory cartridge for use in a redundant memory system. To implement a hot-pluggable memory cartridge in a redundant memory system, control logic to control the sequence of events for powering-up and powering-down a memory cartridge is provided.

Hot replace power control sequence logic

A method of adding memory capacity to a computer system. The computer system comprises a redundant memory system including a plurality of memory cartridges. By powering-down a memory cartridge, adding an additional memory module to the memory cartridge, and powering-up the memory cartridge for each memory cartridge in the system, the system can transition from a redundant mode of operation to a non-redundant mode of operation for each power-down, thus allowing the computer system to remain functional during the addition of the memory module. Alternatively, memory cartridges with higher memory capacity than those currently present in the computer system can be used to replace existing memory cartridges in the computer system, using the same techniques.

Hot-upgrade/hot-add memory

A system and technique for detecting data errors in a memory device. More specifically, data errors in a memory device are detected by initiating an internal READ command or cleansing operation from a set of logic which is internal to the memory system in which the memory devices reside. Rather than relying on a READ command to be issued from an external device, via a host controller, the cleansing logic initiates a cleansing routine in response to an event such as an operator instruction or a periodic schedule. By implementing the cleansing operation, the system does not rely on external READ commands to verify data integrity. Further, a monitoring device is coupled between the cleansing logic and a memory scheduler. The monitoring device provides a feed back mechanism from which to vary the frequency of certain memory requests such as the cleansing and scrubbing operations. The cleansing routine may rely on typical ECC error logging mechanisms and may be used in a RAID memory architecture. Further, the cleansing routine may be used in conjunction with other error logging and correction logic, as well as scrubbing logic.

Memory sub-system error cleansing

A computer system includes a plurality of memory modules that contain semiconductor memory, such as DIMMs. The system includes a host/data controller that utilizes an XOR engine to store data and parity information in a striped fashion on the plurality of memory modules to create a redundant array of industry standard DIMMs (RAID). To optimally run back to back cycles to the memory modules, a technique for providing de-rating parameters such that unnecessary latencies designed into the memory devices can be removed while the system is executing requests. By removing any unnecessary latency, cycle time and overall system performance can be improved.

Memory auto-precharge

A system and technique for correcting data errors in a memory device. More specifically, data errors in a memory device are corrected by scrubbing the corrupted memory device. Generally, a host controller delivers a READ command to a memory controller. The memory controller receives the request and retrieves the data from a memory sub-system. The data is delivered to the host controller. If an error is detected, a scrub command is induced through the memory controller to rewrite the corrected data through the memory sub-system. Once a scrub command is induced, an arbiter schedules the scrub in the queue. Because a significant amount of time can occur before initial read in the scrub write back to the memory, an additional controller may be used to compare all subsequent READ and WRITE commands to those scrubs scheduled in the queue. If a memory location is rewritten with new data prior to scheduled scrub corresponding to the same address location, the controller will cancel the scrub to that particular memory location.

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Cypress, TX, United States of America

John MacLaren