Abstract: A method of connecting and operating three or more devices to an IDE bus under the conditions that: (1) no more than two IDE devices may be active at any given time on the same IDE bus, and (2) cable/trace lengths for the IDE bus may not exceed the limits set forth in the IDE bus standard. The IDE devices are configured for cable select connected to the IDE bus, wherein no more than two of the IDE devices are powered on at any given. Further, those IDE devices which are powered on at a give time, have the appropriate logic level asserted on CSEL line so that only one IDE device powered on at any time is a “Master” device, and only one IDE device powered on is a “Slave”.

Abstract: A method for storing data in a fault-tolerant storage subsystem having an array of failure independent data storage units, by dividing the storage area on the storage units into a logical mirror area and a logical stripe area, such that when storing data in the mirror area, duplicating the data by keeping a duplicate copy of the data on a pair of storage units, and when storing data in the stripe area, storing data as stripes of blocks, including data blocks and associated error-correction blocks.

Abstract: A recording target error rate is selected for one or more of data storage devices, and for each data storage device, a dither value is determined for each read/write head in the data storage device, wherein for each head, using a dither value for writing data, essentially provides the selected recording target error for all the heads.

Abstract: A digital data storage unit, such as tape library, has a multiplicity of storage media slots, each storage media slot for receiving a storage media unit, a plurality of storage media units loaded in particular ones of the storage media slots, a plurality of data transfer devices for writing data to and reading data from the storage media units, a plurality of data transfer device interfaces corresponding to the plurality of the data transfer devices, each data transfer device interface configured for transferring data between a corresponding data transfer device and a host computing environment, a loader mechanism for selectively moving a storage media unit between a storage media slot and one of the plurality of data storage drives, and a storage unit controller connected to the loader mechanism and to the data transfer device interfaces, wherein the storage unit controller is configured for connection to the host computing environment to receive and decode one or more host commands sent by the host computin

Abstract: A process/method for controlling a digital data storage unit including a multiplicity of storage media slots for receiving media storage units, a plurality of media storage units loaded in some of the storage media slots, a plurality of data storage drives each having a unique drive address, a loader mechanism for selectively moving a media storage unit between a storage media slot and one of the plurality of data storage drives, and a storage unit controller connected to at least one host computer. One or more of the data storage drives are reserved as spare data storage drives wherein the spare data storage drives are masked from the host computer such the spare data storage drives are not directly accessible by the host computer. The storage unit controller receives and decodes host commands including a source address corresponding to a storage media slot location, and a destination address corresponding to a data storage drive specified by the host computer.

Abstract: A digital data storage unit having: a multiplicity of media storage slots for receiving a plurality of storage media units, each storage media unit including a storage medium and a memory device (MD) for storing data, the memory device including an interface for transferring data to and from the memory device; one or more media data transfer devices physically distributed within the digital data storage unit in relation to the storage media slots for transferring data to and from the storage medium in each storage media unit; a loader mechanism for selectively moving a storage media unit between a storage media slot and said media data transfer devices for transferring data to or from the storage medium in the storage media unit; at least one memory data transfer device (MDTD) including a memory device interface for transferring data to and from the memory device of one or more storage media units; and a controller within the digital data storage unit, configured for controlling the loader mechanism to move s

Abstract: A network storage device having a network controller card and a data storage device is described herein the card and storage device are either enclosed in a small from factor unit or assembled together to fit within a standard hard disk drive bay in a computer. The combination of a controller card and storage device is designed to transfer files from and to a network using standard network file protocols. As the network storage device does not process the files, much of the computational overhead of a network server can be eliminated, resulting in a simpler device capable of faster file exchange.

Abstract: A method of memory management in a computer system comprising memory. The method includes the steps of: in response to requests for allocation of memory blocks that remain allocated for different durations, allocating each memory block from one of a plurality of regions in the memory based on the duration that the memory block is to remain allocated; and maintaining a plurality of memory segments of one or more sizes in the memory, and in response to a request for allocation of a memory block if the requested block size is less than a predetermined size, then allocating the requested block from among said segments, otherwise allocating the requested block from another portion of the memory. The number of data segments are changed in relation to memory requests. Further at least a portion of the memory is allocated to a cache having one or more buffers. The cache buffers can be allocated for non-cache use, including increase the number of said data segments, and are then deallocated back to the cache.

Abstract: A methodology for designing an implementing high rate RLL codes is optimized for application to 10-bit ECC symbols, and provides rate 20/21, rate 50/51, rate 90/91 and other modulation code rates for use in magnetic recording channels. A relatively small subcode encoding—one easy to implement—is applied to a portion of the input stream, and the resulting base codeword is partitioned into nibbles that, in turn, are interleaved among the unencoded ECC symbols. Code constraints on the subcode word nibbles depend upon the values of adjacent unencoded symbols. The resulting codes provide excellent density and error propagation performance.

Abstract: A data recording device including recording media having a set of at least two alternate regions thereon for each data segment, whereby each data segment has a corresponding set of at least two alternate regions on the recording media; a transducer positionable to write data on and read data from the recording media; and a controller for recording one or more data segments on the recording media in response to one or more write commands, the controller including a selector wherein for each of said one or more data segments the selector selects one region from the set of alternate regions corresponding to that data segment and positions the transducer to write that data segment on the selected region. To reduce the access time for each write operation, the selector selects the one region from the set of alternate regions based on shortest access time required to access each of the regions in the set of alternate regions for recording data.

Abstract: A circuit for monitoring and detecting data transfer protocol errors that occur during asynchronous transfer of data over a data bus. The circuit monitors bus request/acknowledge control lines in accordance with a predetermined handshaking protocol. In the event that an undefined or illegal logic state is detected on the data bus request or acknowledge control lines, the circuit provides an error value to the data sending entity. As a result of receiving this error value, the data sending entity can retry the data transmission over data bus.

Abstract: An apparatus for sustaining data throughput and methods of operating the same result in a drive apparatus that reduces overhead associated with recovery from write faults. The drive apparatus for sustaining data throughput having a file allocation unit including a plurality of sectors for storing data comprises a write controller coupled to the file allocation unit configured to write data to the plurality of sectors, a write fault detector coupled to the write controller and the file allocation unit configured to detect a write fault, and a write fault controller coupled to the write controller, the write fault detector, and the file allocation unit responsive to a detected write fault to skip a defective sector and restart the write controller to continue writing data to the plurality of sectors.

Abstract: A method reducing data format overhead in a storage device. A sequence detector includes a series of states and a path memory of predetermined length. This method includes steps of writing a predetermined shortened pad pattern at the end of a user data field pattern to a signal-degrading storage medium such as magnetic tape or disk; generating samples during read back of the user data field pattern and the shortened pattern; and, controlling the sequence detector during receipt of pad samples to converge at only one or several predetermined detector states during a convergence sequence. The convergence sequence, and the detector pad are shorter than a sequence needed to traverse the entire length of the path memory. The final state reached during the sequence can be used to provide an accurate estimate of a last user data bit of the user data field pattern.

Abstract: A segmentation method of a frame of image information including a plurality of spaced DNA spot images corresponding to a plurality of DNA spots. The image information includes image intensity level information corresponding to said DNA spots. The frame is stored in a memory device and a set of image information within said frame including a selected set of the DNA spot images is selected. A grid including a plurality of spaced grid points corresponding to said selected DNA spot images is generated, such that each grid point includes position information indicating the position of the grid point within said frame.