摘要:
A drive array controller is provided that serves as an interface between both stand-alone SCSI devices as well as SCSI devices that form a composite drive. Since an AHA emulation interface is incorporated on the drive array controller, the drive array controller is compatible with conventional AHA device drivers that drive stand-alone peripheral devices such as SCSI CD-ROM units and SCSI tape drives. The drive array controller includes a SCSI pass-through driver that extracts a SCSI command descriptor block from a command control block created by the AHA device driver. The drive array controller further provides a separate peripheral access channel to support high speed composite drive operations through a composite device driver. Since the AHA emulation interface and a composite drive interface are provided on a common peripheral board, only one EISA expansion slot is occupied.
摘要:
A drag-reduction system incorporated within an inwardly stepped underside of a boat hull for reducing a degree of water pressure forces exerted upon the boat hull during travel of the boat upon a body of water. A plurality of spaced apart rollers are secured at a generally aft location of the boat hull associated with the inwardly stepped underside and extend in parallel spaced apart fashion and perpendicularly to a longitudinal water flow across the boat hull experienced during propulsion of the hull. An elongate and planar shaped belt of a water impervious material having an established width and defining a continuous extending and closed loop is mounted over the plurality of spaced apart rollers. A first linearly extending location of the continuous belt is recessed within the stepped underside of the hull and a second linearly extending location is in contact with the longitudinal water flow. The second linearly extending location of the belt is capable of being translated in a direction consistent with the longitudinal water flow across the boat hull. A single drive roller or pair of drive rollers associated with the plurality of spaced apart rollers is capable of driving the belt at a velocity equal to or greater than a velocity of the longitudinal water flow traveling along the boat hull.
摘要:
A relatively permanent and indestructible covering (10) utilizes a plurality of single ply tiles (12) which are bonded to a base floor surface (14) and provided with a protective coating in a single step by applying at least one protective bonding coating, such as an epoxy coating, over the top of plurality of tiles. To facilitate bonding to base floor surface, each of the plurality of tiles (12) are formed with a plurality of holes passing through the surface thereof. A color finish coating can also be provided over the top of the array of tiles by utilizing a protective bonding coating having a paint or paint-like quality. In a preferred embodiment, the tiles (12) are formed from a metal such as aluminum.
摘要:
A system for reducing the amount of power consumed by a battery operated computer device is disclosed. A microcontroller continuously monitors the activity of at least one I/O device and sets an activity state variable (ASV) associated with the I/O device accordingly. Upon each the expiration of a preselected time period, the microcontroller examines the state of the ASV to determine whether the I/O device was active during the expired time period. If so, the I/O device is caused to operate in a full power mode; otherwise, the I/O device is caused to operate in a reduced power consumption mode. In one embodiment, the I/O device is capable of operating in more than one reduced power consumption mode, in which case, responsive to a determination that the I/O device was not active during the expired time period, the I/O device is caused to operate in the next lowest power consumption mode. In an alternative embodiment, the frequency with which timer interrupts are generated is automatically adjusted after the expiration of each time period.
摘要:
A CD ROM server comprises a CD ROM drive and an array of hard disk drives. Means are provided for copying data from the CD ROM drive to the array of hard disk drives, and for deleting data from the array of hard disk drives, upon receipt of copy and delete requests, respectively, from a host computer system. Means are provided for the host computer to read data from the array of hard disk drives in the CD ROM format that the data had been stored in on the CD ROM. Means are also available to implement RAID technology with the array of hard disk drives for data reconstruction, striping, and redundancy. Means may be provided for the host computer to communicate directly with any SCSI devices connected to the server.
摘要:
A computer system including a host CPU, a primary PCI bus coupled to the CPU, and a bus adapter coupled to the primary PCI bus, wherein the host CPU can access peripherals comprised in the bus adapter even when the bus adapter is inoperable. The bus adapter includes a PCI to PCI interface controller which includes a primary PCI interface for coupling to the primary PCI bus and a secondary PCI interface bridge for coupling to a secondary PCI bus. Peripheral bus interface logic is coupled between the primary PCI interface and the secondary PCI interface, and this interface logic couples to various peripheral devices, including ROM/Flash memory and non-volatile static random access memory (NVSRAM). According to the present invention, a host utility executing on the CPU can access the peripheral devices without having to access the secondary PCI bus. Thus, if the secondary PCI bus becomes inoperable or the local processor is unable to boot, the host can still access the memory in the peripheral devices because the peripheral interface is effectively decoupled from the secondary PCI bus and the local processor. The present invention includes a host utility which can update the Flash memory, thereby providing a cost-effective and efficient mechanism for restoring code in a corrupted Flash device on a failed board. This also enables the Flash memory to be programmed for the first time during manufacturing. The system and method of the present invention allows the host CPU to access the NVRAM to obtain event failure information even if the secondary PCI bus has failed.
摘要:
A peripheral resource controller such as a caching disk array controller is provided for controlling the transfer of data between a host bus and a peripheral resource, such as an array of hard disk drives. The peripheral resource controller includes a bus interface controller for providing an interface between the host bus and a local bus of the peripheral controller. The bus interface controller further includes a peripheral bus interface which accommodates accesses to a peripheral bus and a DMA controller for controlling direct memory access operations between a local memory of the peripheral controller and a system memory of the host computer. A DMA transfer list memory is coupled to the peripheral bus for storing DMA transfer information. The DMA controller fetches host and local address as well as block size information from the DMA transfer list memory to thereby effectuate DMA operations. In one specific implementation, a local processor of the peripheral controller loads the DMA transfer information into the DMA transfer list memory by causing the execution of one or more memory write cycles on the local bus. A local bus interface of the bus interface controller responds as a target and routes the data to a peripheral bus interface. The peripheral bus interface, which functions as a master of the peripheral bus, responsively effectuates corresponding cycles on the peripheral bus to write the DMA transfer information into the DMA transfer list memory.
摘要:
A disk drive array with a controller which provides: dynamic remapping for grown defects in the disk drives, multi-thread request processing with a variable number of forkings, defect tracking with both logical and physical lists, guarded writes of less than a full stripe optimized by selectably using the redundancy to limit the number of sectors involved, association of multiple operations with a single disk request in order to facilitate error handling, use of an access hiatus as indication of further opportunity to rebuild data in background, and scatter/scatter (bidirectional scatter/gather) operations.
摘要:
A fault tolerant disk array subsystem is provided that includes a plurality of data drives for storing real data and a parity drive for storing redundant data. Each data drive is associated with a dedicated write-through cache unit and the parity drive is associated with a dedicated write-back cache unit. An array scheduler schedules read and write operations to access the data drives and includes a parity control unit for updating parity information when new data is written to one of the data drives. Since a write-back caching technique is used to store updated parity information, the write latency of the parity drive does not limit the write-throughput of the disk array subsystem. Furthermore, since a non-volatile memory unit is provided to store the addresses of any dirty parity information within the write-back cache unit, parity information can be reconstructed in the event of a power failure. The disk array subsystem provides a low cost, mass storage resource having improved write performance characteristics. The disk array subsystem also accommodates data redundancy to allow data restoration in the event of disk failure.
摘要:
A disk controller for a disk drive array which maintains two representations of all drive defects. The controller maintains a logical defect list that is used to maintain the sector remapping structure when reconstructing redundancy information. The controller also maintains a physical defect list that is used to preserve known defect information on a physical disk basis. The physical defect list stores the defects even if the logical configuration of the disks changes. When the controller of the present invention determines that a block of data is bad, the controller allocates space for the respective stripe in an alternate block, recovers the data in the stripe and writes the recovered data to the newly allocated stripe. The controller then updates the remap tables in memory with the remap information. On each disk access, the controller searches the logical defect list to determine if the access involves one or more bad blocks. When a failed disk is replaced, the controller rebuilds the data from the failed drive using the remaining data and parity. The controller also uses both the logical and physical defect lists to unmap remapped sectors which were originally remapped due to defective sectors on the replaced disk drive.