Cray Incorporated

Roger A Bethard

Kelly J Marquardt

David R Resnick

Gerald A Schwoerer

Van L Snyder

Michael L Steinberger

Alan M Grossmeier

Steven Lee Scott

Dennis Charles Abts

Michael Higgins

Gregory J Hubbard

R Paul Dixon

A memory daughter card (MDC) is described, having a very high-speed serial interface and an on-card MDC test engine that allows one MDC to be directly connected to another MDC for testing purposes. In some embodiments, a control interface allows the test engine to be programmed and controlled by a test controller on a test fixture that allows simultaneous testing of a single MDC or one or more pairs of MDCs, one MDC in a pair (e.g., the 'golden' MDC) testing the other MDC of that pair. Other methods are also described, wherein one MDC executes a series of reads and writes and other commands to another MDC to test at least some of the other card's functions, or wherein one port executes a series of test commands to another port on the same MDC to test at least some of the card's functions.

Memory-daughter-card-testing method and apparatus

An apparatus includes a SerDes circuit and a link control block (LCB). The SerDes circuit is a first end of a SerDes circuit pair of a SerDes lane. A SerDes lane includes the SerDes circuit pair coupled by a communications medium. The LCB includes an error tracking circuit and a controller. The controller includes an error recovery module configured to retry a data communication when an error is detected and deactivate the SerDes lane when a rate of errors on the SerDes lane exceeds a threshold error rate value. Other devices, systems, and methods are disclosed.

Inter-asic data transport using link control block manager

A system and method for addressing memory and transferring data, which in some embodiments include one or more processor translation look-aside buffers (TLBs) and optionally one or more I/O TLBs, and/or a block transfer engine (BTE) that optionally includes a serial cabinet-to-cabinet communications path (MLINK). In some embodiments, the processor TLBs are located within one or more common memory sections, each memory section being connected to a plurality of processors, wherein each processor TLB is associated with one of the processors. The BTE performs efficient memory-to-memory data transfers without further processor intervention. The MLINK extends the BTE functionality beyond a single cabinet.

System and method for accessing non processor-addressable memory

A system and method for speculative forwarding of packets received by a router, wherein each packet includes phits and wherein one or more phits include a cyclic redundancy code (CRC). A packet is received and phits of the packet are forwarded to router logic. A cyclic redundancy code for the packet is calculated and compared to the packet's cyclic redundancy code. An error is generated if the cyclic redundancy codes don't match. If the cyclic redundancy codes don't match, a phit of the packet is modified to reflect the error, the CRC is corrected and the corrected CRC is forwarded to the router logic along with the phit reflecting the CRC error. At the router logic, a check is made to see if the packet is still within the router logic. If the packet is still within the router logic and there was a CRC error, the packet is discarded. If, however, the packet is no longer within the router logic and there was a CRC error, the packet is modified so that the next router discards the packet.

Speculative forwarding in a high-radix router

Memory-daughter-card-testing apparatus and method

A memory controller and method that provide a read-refresh (also called 'distributed-refresh') mode of operation, in which every row of memory is read within the refresh-rate requirements of the memory parts, with data from different columns within the rows being read on subsequent read-refresh cycles until all rows for each and every column address have been read, scrubbing errors if found, thus providing a scrubbing function that is integrated into the read-refresh operation, rather than being an independent operation. For scrubbing, an atomic read-correct-write operation is scheduled. A variable-priority, variable-timing refresh interval is described. An integrated card self-tester and/or card reciprocal-tester is described. A memory bit-swapping-within-address-range circuit, and a method and apparatus for bit swapping on the fly and testing are described.

Apparatus and method for memory with bit swapping on the fly and testing

Apparatus and method for testing memory cards

Translation lookaside buffer-based memory system and method for use in a computer having a plurality of processor element

An adaptive computing system having trainable components for eliminating harmful effects of skew caused by the length of the transmission line or introduced by data-dependent sources. A transmitter provides a data value to the transmission line according to an output clock signal and precompensates the transmission line when a change in the data value is detected. A receiver is communicatively coupled to the transmitter by the transmission line and has a plurality of data latches. Each data latch stores a data value received from the transmission line according to a unique clock signal. All configuration and training of the adaptive transmitter and receiver is accomplished through a standard boundary scan register that complies with IEEE/ANSI standard 1149.1-1990.

Growing community of inventors

Chippewa Falls, WI, United States of America

Roger A Bethard