Abstract: A method and system for variable speed scrolling through a viewable object within a data processing system such as a computer, a television, a kiosk display or hand-held digital product. A portion of the viewable object is displayed within a display window within a data processing system in conjunction with a scroll bar having a slider and one or more scroll buttons associated therewith or some other suitable method of controlling video or audio displays. User selection of the slider or a scroll button initiates scrolling of the viewable object so that additional portions of the viewable object may be displayed. As the viewable object is scrolled, the scroll speed is dynamically varied in response to the content of the viewed portion of the viewable object.

Abstract: A data storage library subsystem and a method for storing, and maintaining and tracking synchronism between, multiple copies of identifiable data volumes between hosts and a plurality of data storage libraries, and transparent to the hosts. The library controller of each library provides an updatable synchronization token directly associated with each data volume. A plurality of directors are provided, each separate from and coupled to the hosts and each separate from and coupled to each data storage library. Each director responds to ones of separate, partitioned access addresses addressed by the hosts. The responding director supplies each data volume supplied from a host to all of the data storage libraries, and updates each synchronization token directly associated with the supplied data volume. Thus, the directors store duplicate copies of the data volume in the data storage libraries without involvement by the host.

Abstract: A data storage library system and a method for storing, and maintaining and tracking synchronism between, multiple copies of identifiable data volumes between hosts and a plurality of data storage libraries, and transparent to the hosts. The library controller of each library provides an updatable synchronization token directly associated with each data volume. A plurality of directors are provided, each separate from and coupled to the hosts and each separate from and coupled to each data storage library. Each director responds to ones of separate, partitioned access addresses addressed by the hosts. The responding director supplies each data volume supplied from a host to all of the data storage libraries, and updates each synchronization token directly associated with the supplied data volume. Thus, the directors store duplicate copies of the data volume in the data storage libraries without involvement by the host.

Abstract: In an automated retrieval library with virtual storage for identifying particular cartridges in the library to protect the data in the virtual volume from overwriting in import and export operations. A convenience input/output station is set to an import mode with export/import virtual tape servers. Possible import cartridges are categorized upon insertion to prevent their access by the host computer. Recovery from erroneous identification is provided.

Abstract: An analog SCSI switch comprising initiator device ports, target device ports and a controller utilizing at least one analog multiplexor circuit is connected between a SCSI interface and multiple SCSI devices. The controller monitors the SCSI bus and controls all interfaces and ports. By monitoring the SCSI bus, the controller is constantly informed of the arbitration, selection and re-selection acts of the initiator device or target devices. An analog multiplexor circuit selectively connects the initiator device and target device directly, allowing direct communication between the initiator device and a particular target device for duration of the connection. Logic for the controller, contained in the switch onboard memory, utilizes a secondary logical unit number of a target device to map a target device port. Utilizing the analog multiplexor circuit, the switch connects the initiator device port to a selected, mapped target device port.

Abstract: In an optical data storage device for storing data on a removable optical disk in a continuous sequence of sectors or blocks, the input data buffer may be subject to under-run. An under-run detector is disclosed which is responsive to the buffered data comprising less than a sector of data for indicating an under-run, and a padding provider is disclosed which is responsive to the under-run indication for providing padding characters for formatting into sectors. The sectors may be provided with headers indicating the sectors as padding. A reading device for reading the data sectors and providing the data to a host detects padding and prevents the padding data from transmission to the host.

Abstract: Servo errors can be avoided in a bi-directional reel-to-reel tape transport in which magnetic tape is moved in either of two opposite directions for data recording by providing a fine-line tachometer for each reel and a directly coupled tension sensor. Control of tape speed is implemented in a servo algorithm that uses tachometer inputs to determine parameter values for generating reel motor drive currents. If the linear velocity of both reels is the same then the tension output must be within a tolerable range. The directly coupled tension output provided an is indication of the actual current of the tension sensor. The difference between the linear velocities of the tape from each reel is calculated and monitored together with the tape tension. A trip level is set when an error occurs to stop tape motion and permit recovery without damaging the tape.

Abstract: Disclosed are a shared direct access data storage system and sharing method for use with both an MVS data processing system and a data processing system employing FBA data, for storing data set records received from the MVS data processing system. A CKD controller receives the data set from the MVS data processing system. An FBA controller and disk data storage provides direct access to FBA records by the FBA data processing system. A mapping element maps the data set records from the MVS data processing system into FBA data records with fixed blocks. The received data set records are uniformly sized, and the mapping element converts the uniformly sized records into smaller sized fixed blocks, with the size of the uniformly sized records being an even multiple of the smaller sized fixed blocks. A map translates the data of the first record of the data set into the block id of the first block and continues to map the data set into a continuing sequence of fixed blocks.

Abstract: A method for balancing workloads in media library access systems that provide multiple accessors disposed within a library. Each of the accessors is assigned a given zone of primary access wherein each of the zones of primary access has at least one boundary. Accessor usage is calculated by adding a score for each access to total accesses for each accessor. The totals are evaluated to determine that one or more of the boundaries requires adjustment and the boundaries are adjusted in accordance with the evaluation. By changing the average span of each accessor dynamically, the method can equalize the use of each accessor, minimizing library latency.

Abstract: A laptop computer has a base and a cover with a display monitor that are connected together by a hinge. The base and cover have congruent trapezoidal shapes that give the laptop a unique appearance. A pair of segregated right and left keyboards are mounted to the base. Each keyboard is rotated by a small angle from the center of the base to align with the natural position of the arms of the user. The keyboards are further articulated such that their front ends are elevated relative to their rearward ends. Alternate embodiments of the invention utilize various mechanisms for articulating the keyboards. In addition, the keys on each keyboard may be arranged in a curvilinear formation. The laptop has a wedge that is slidably mounted to the rearward end of the base for varying the angle of inclination of the keyboards. The wedge can raise or lower the angle of the keyboards to suit the preference of the user.

Abstract: An array of independent disk drive assemblies are interconnected to a fiber optic cable in a backplane. Each drive assembly has an optics interface for engaging one of a series of connectors on the backplane. Data is accessed and stored on the disk drives by a host computer via operational signals sent through the cable. The drives are hot-pluggable into the cable connectors through their interfaces. The connectors have pivot members that are movable between open and closed positions. The cable is joined to each pivot member such that a single optical joint is formed at each connector. The interfaces on the drives plug into the pivot members to access the data on the cable. When a drive is removed from a connector, the pivot members close and allow the optical transmission to continue downstream on the cable with minimal signal losses.

Abstract: Storage shelves of a mass data storage library are organized into a plurality of subsets for the purpose of conducting an inventory of media stored in the shelves. In response to an inventory command, the inventory is conducted in a predetermined order by subset. Upon completion of the inventory of each subset, the completion is posted in a list. A command input detects newly issued commands (subsequent to the inventory command), and places them in a queue. After completion of the inventory of a subset, and upon detecting a command for a non-inventory process (such as a media move), the inventory is interrupted and stopped. The move is conducted, and, upon completion of the move, the inventory is resumed. If a newly issued command is an inventory command, the inventory command is incorporated into the inventory process.

Abstract: In an optical data storage device for storing data on a removable optical disk in a continuous sequence of sectors or blocks, the input data buffer includes an ECC process. A padding provider is disclosed which is responsive to an under-run indication for providing padding characters for formatting the storage into sectors. The sectors may be provided with headers indicating the “padding sectors”. A reading device for reading the data sectors and providing the data to a host detects padding and prevents the padding data from being transmitted to the host.

Abstract: Disclosed are a method and a detector for adaptively detecting servo gaps in a timing based servo pattern prerecorded on a variable velocity media. The timing based servo pattern has groups of repeated pairs of non-parallel transition stripes arranged in bursts, the bursts separated by servo gaps whose length is variable. A servo system sensor senses the transition stripes in the longitudinal direction of the media. A group interval detector coupled to the sensor detects the timing interval between the same slope transition stripes of two sequential groups of bursts. A divider divides the detected group timing interval by a predetermined divisor to provide a divided timing interval gap detection threshold. A sequential stripe interval detector coupled to the sensor measures the timing interval between stripes, and a comparator compares the divided timing interval and the timing interval, identifying a servo gap upon the measured timing interval at least equaling the gap threshold.

Abstract: A method and apparatus for detecting data written on a recording medium are disclosed. The recording medium, such as an optical or magnetic medium, is initially sensed by a transducer to produce an analog data signal waveform. The analog data signal waveform is then digitized by an analog-to-digital convertor to produce a set of digitized data samples. The set of digitized data samples may be equalized to reduce noise. Subsequently, a mid-point sample is inserted between each two samples within the set of equalized data samples utilizing a mid-point interpolation algorithm. With the additional points provided by mid-point interpolation, the absence or presence of a detection event, such as a peak or a transition, between every two samples within the set of equalized data samples are determined.

Abstract: Disclosed are a method, a storage management system, an article of manufacture comprising a computer readable medium, and a computer program product for saving a recovery plan file for a storage management server. The storage management system has a plurality of storage management servers at sites remote from one another coupled by a server-to-server infrastructure. A recovery plan file is saved for one of the storage management servers at one of the sites by establishing the server as a source for its recovery plan file. Another storage management server at a site remote from the source server site is established as a target for the recovery plan file. The source server transmits the source recovery plan file from the source server to the target server at the remote site over the server-to-server infrastructure. The source recovery plan file is managed at the target server according to defined criteria, for placement, backup, migration and expiration under the control of the source server.

Abstract: Disclosed is a method (and apparatus) for optimizing disk access operations which span multiple logical disk partitions and multiple disk drives. The disclosed method makes optimum use of concurrency in the software without causing poor performance due to contention for seeks in a disk drive.

Abstract: A method, system, and computer program product for protecting data of a shared access data storage system from being overwritten, where the data storage system includes a device which is shared by separate hosts over at least two logically or physically distinct communication paths. An overwrite protection facility operates the data storage system controller processor independently of the hosts to automatically protect the device upon the occurrence of a write command for the device. The protection allows only the communication path issuing the write command, and communication paths in the same group as the issuing communication path, to issue commands resulting in movement of the media on the device. Commands not resulting in movement of the media are allowed from any communication path. The protection continues until specifically released by a “MEDIA REMOVAL” command. The protection, in one embodiment, is by means of a prime protected attribute for the device-communication path pair.

Abstract: Identifying most recent redundant copies of identifiable data volumes stored in a plurality of data storage libraries which are coupled to a plurality of directors. To update a data volume, an initiating director attempts to set a current token “inconsistent” flag to potentially down level copies of the data volume on each lagging library. Upon failing to receive notification of any successful setting of the current token “inconsistent” flag from any of the lagging libraries, the director forwards the request to the other directors, which attempt to set the current token “inconsistent” flag for the volume at any lagging library from which no notification has been received. Upon all of the other directors responding to the initiating director, and upon the other directors indicating failure to set the “inconsistent” flag at the lagging library, all the directors list the volume and a new token as an entry in a “hot token” list.

Abstract: A synchronous interface is provided for an asynchronous channel, for example, a read channel for a variable velocity magnetic tape, the channel providing asynchronous samples of an input signal from a fixed clock. The input signal, for example, comprises PRML data, written based upon synchronous write clock boundaries. The synchronous interface of the invention presents estimated synchronous samples at estimated write clock boundaries to allow decoding of the input signal. A phase estimator is coupled to the asynchronous channel for estimating the timing offset of the input signal synchronous write clock boundaries from the asynchronous samples. A sample estimator is coupled to the asynchronous channel and to the phase estimator for estimating, from two sequential asynchronous samples bounding an input signal synchronous write clock boundary, the input signal amplitudes at the estimated timing offset from the asynchronous samples.