Abstract: An automated cartridge library (30) has plural cartridge receiving units which are precisely locatable so that a transport device (300) can accurately move a cartridge (90) between at least two of the cartridge-receiving units. The cartridge-receiving units and/or calibration cartridges inserted therein have an indicia (190) which is of contrasting reflectivity, the indicia having at least two sides (191, 192) which meet at a vertex (193). An illumination source (340) on the cartridge transport device makes two sweeps (Y1, Y2) of an illuminating beam over the indicia. Illumination transitions as detected by a sensor (350) during the two sweeps are used to determine a location of the indicia vertex (193). In the case of a cartridge-receiving unit being a multi-celled cartridge magazine, a rear wall (220) of the magazine has an aperture (222) for each cell.

Abstract: An automated cartridge library (2230) has a cartridge transport system (2240) which transports cartridges of information storage media between a cartridge storage section (2234) and a drive section (2238). The cartridge storage section includes a plurality of stacked magazine-bearing drums (2235) and a entry/exit magazine carrier (2236). The entry/exit magazine carrier linearly reciprocates from a docking position to an entry/exit port position, thereby carrying an entry/exit magazine (70) carried thereby between the docking position and the entry/exit position. The entry/exit magazine is accessible by the cartridge transport system when in the docking position, and manually accessible through a entry/exit door (2310) when at the entry/exit position. At the entry/exit position the entry/exit magazine carrier facilitates removal of the entry/exit magazine or cartridges therefrom through the entry/exit door but precludes manual penetration into the interior of the cabinet beyond the magazine carrier.

Abstract: A magnetic tape drive (20) has features for counteracting inverted insertion of a tape cartridge. A loading tray (30) of the drive has a displaceabie dustcover release element (72) which actuates a release lever of a dustcover of the cartridge when the cartridge is properly inserted into the tray but which displaces when an inverted cartridge is inserted into the tray. In one embodiment, the displaceable dustcover release element resiliently protrudes through an aperture (70) of a bottom wall (60) of the tray and into an interior of the tray. The tray has a bottom wall with a bottom wall edge (90) configured to extend over a dustcover lid of an inverted cartridge inserted into the tray and thereby preclude catching of the dustcovet on the bottom wall. Moreover, the tray has inverted cartridge stop members (82) provided at a position to abut an inverted cartridge upon full insertion of the inverted cartridge into the tray.

Abstract: Method and apparatus are provided for re-recording of a frame on magnetic tape (22) when a first recording of the frame is determined to be defective. A frame whose first recording is defective is re-recorded at a spare or reserved location on the tape. The reserved location is dedicated to re-recording of frames, and otherwise cannot have data stored therein. The tape contains a defect map frame (326) which is used to pair physical locations of defective frames with the reserved location whereat the frame is re-recorded. In one embodiment, the reserved location whereat a frame is re-recorded is a reserved physical frame on the same track in which the defective frame is recorded. In another embodiment, the reserved location is on a reserved portion of a track (TG39R) which is not the original track (TG39) upon which the frame is recorded. For embodiments having multi-channel or multi-track frames, the reserved location employs a corresponding plurality of tracks.

Abstract: A method of determining a vertical (e.g., axial) offset distance between a first and a second transducing element of a helical scan tape drive involves varying a ratio of a rotational velocity of the drum to a linear tape speed of the tape while transducing a magnetic pattern between at least one of the transducing elements and the tape. The pattern transduced is read and used to determine information pertaining to the vertical offset distance. In one mode of the invention, a vertical offset distance between a read transducing element and a write transducing element is determined by using a peak magnitude of a read signal. In a second mode of the invention, the linear tape speed is first set to a value at which tracks recorded by a second write transducing element are rendered unreadable, and a resultant noise signal acquired.

Abstract: Methods of calibrating a helical scan recorder include transporting a storage media past a drum at a controlled linear velocity and recording tracks on the media using a write head. During a read-after-write operation, servo signals recorded on the tracks are read. The servo signals from the tracks are used to determine an axial offset variance of the write head and a read head on the drum. In one mode, calibration is achieved for a first helical scan recorder which does not have a capstan, by installing a drum of the recorder in a second helical scan recorder, using the second recorder to record servo signals on two tracks, reading the servo signals from those two tracks in the second recorder, using the servo signals to determine axial offset variance, and storing a value indicative of axial offset variance in a memory of the first recorder. The axial offset variance is used in a write splice operation and, in one mode, to determine linear velocity of the media.

Abstract: In serpentine recording on magnetic tape (32), a warning marker (CEW) is generated and recorded on tape in a write mode and is read in a read mode. The warning marker indicates that a head is approaching a boundary position on the tape at which the head must change tracks in order to continue recording or reading frames. The warning marker is preferably included in an auxiliary portion of at least some frames. In one embodiment, the warning marker has a value related to a number of frames that can yet be recorded on the track before the boundary position is encountered. Monitoring of the warning marker serves to apprise the drive of a potential need to cache data in anticipation of a change of track. Caching of data can occur either by sending a caching signal to the host, or can occur internally in the drive without taxing the drive's buffer. In the drive-internal caching, the relative speed between the tape and the head is adjusted in anticipation of the head being repositioned for a change of track.

Abstract: A computer program product embodied in a memory (FD1, FD2) implements procedures for replicating the contents of a first hard disk on a second hard disk. In a backup operation mode, the program enables a suspect computer (20S) to copy or backup sectors of its hard disk (22S) onto a temporary storage media (84) without recording on hard disk (22S). A user-designated signature, dimensioning parameters of hard disk (22S) and first checking information is also recorded on the temporary storage media (84, FD3). In a restore operation mode, the program enables a lab computer (20L) to read sectors of the hard disk (22S) from the temporary storage media (84) and to record sectors of first hard disk (22S) on the hard disk (22L) in accordance with the dimensioning parameters of hard disk (22S).

Abstract: Write splicing for a helical scan tape drive (30) involves, upon occurrence of a predetermined condition such as a buffer low condition, recording an indication of a tape transport transition (ITTT) on tape (31) and then recording dummy helical stripes (DSd1-DSdn) having deviant form as the magnetic tape is decelerated to a stop. After the predetermined condition is overcome, further deviant, dummy stripes (DSa1-DSan) are recorded as the tape is accelerated back to nominal tape transport speed. At the nominal tape transport speed, non-deviant stripes (S2) containing user data are again recorded on tape. A distance separating a first set of stripes ?S1! (recorded prior to the occurrence of the predetermined condition) and a second set of stripes ?S2! (recorded upon again attaining the nominal tape transport speed) is an integer multiple of the track pitch (P) of a non-deviant stripe. The write splice is thus performed without reversing the direction of tape transport.

Abstract: Method, apparatus and program are provided for replicating an image of a source hard disk (22) onto a larger destination hard disk (22') in a manner that renders available the non-image-utilized sectors of the destination hard disk. Destination disk address dimensions are obtained from a drive (24') which handles the destination hard disk. Both source disk address dimensions and an image of sectors stored on the source disk are obtained from a temporary storage media (84). The image of the source disk is recorded on the destination disk (22'), but address values stored in the sectors of the image are adjusted to be based on the destination disk address dimensions rather than the source disk address dimensions.

Abstract: An interface apparatus or Nest (30) fits into a peripheral slot (24) connected to an IDE bus (60) of a host computer. IDE devices, such as magnetic tape drives and hard drives, are hot swapable in and out of Nest (30) while the IDE bus is active. The Nest isolates the IDE device from the active IDE bus until such time (e.g., initialization of the IDE device) as connection of the IDE device to the IDE bus will not corrupt the IDE bus, after which time the Nest connects the IDE device to the IDE bus while the IDE bus is active. A nest driver (230) is executed for computer systems (200) which tend to establish a permanent inventory of IDE devices upon system boot-up. The nest driver determines whether a Nest is connected to the host; determines whether an IDE device has been inserted in the Nest; and determines when the IDE device in the Nest has been initialized.

Abstract: A bezel (100) mitigates cartridge over ejection from a tape drive, the tape drive receiving and ejecting a cartridge of magnetic tape for performing recording and reading operations with respect to the magnetic tape. The bezel (100) comprises both a bezel plate (102) and a pair of cartridge braking projections (120) attached thereto. The cartridge braking projections partially extend into a cartridge slot (104) and retard motion of a cartridge travelling through the slot. The cartridge braking projections (120) are resilient and bidirectionally flexible, preferably being formed of cellular urethane. The cartridge braking projections (120) extend into the slot by a predetermined distance above a lower cartridge plane (115). In one embodiment, the bezel (100) is attached to a rack which accommodates the tape drive.

Abstract: A cartridge rack (60) houses a plurality of data storage cartridges (62) in an automated cartridge library (30). The rack comprises four sidewalls connected to define a rectangular perimeter of the cartridge rack, a backwall, and a plurality of ribs bridging opposite ones of the sidewalls, thereby forming a plurality of cartridge-receiving slots. Ramps (164, 120) are formed on an exterior surface of at least one of the side walls. An orientation fin (172) orthogonally extends from an underside of the backwall. At least one of the ramps (164) is a scalene triangularly-shaped crown ramp which is centrally located between opposing ones of two other of the sidewalls. Others of the ramps are feet ramps (120) formed on an opposite one of the sidewalls from the sidewall upon which the crown ramp (164) is formed. Apparatus is also provided mounting a data cartridge (60) in the cartridge library (30), including a rack mount (110) having a base plate (112).

Abstract: A magnetic tape drive dynamically adjusts a transport rate of tape (32) in accordance with a host data rate. The host data rate is assessed in relation to a data fill level of a buffer (116). A controller (130) of the drive compares the data fill level of the buffer with a buffer normalization value and generates an adjustment value for adjusting a signal indicative of the desired linear velocity of the tape. In one embodiment, the controller also dynamically changes the buffer normalization value to reflect e.g., historical performance of the host. In another embodiment the controller adjusts the transport rate when a head (100) is within a predetermined distance of a boundary point whereat the head must change tracks.

Abstract: A power amplifier (18) for driving a brushless DC motor (22) includes a processor (40) which receives a signal indicative of motor situational usage and generates a mode state signal indicative of which one of a plurality of amplification modes is to be implemented in response to the received signal. The amplification modes include a linear mode and a switching mode, with the switching mode including a two quadrant switching mode and a four quadrant switching mode. The amplifier (18) further includes a controller (50) which, in response to the mode state signal, generates control signals for each of coil drive circuits (26) associated with the motor. Further, in response to a signal indicative of motor situational usage, processor (40) generates a power state signal which causes controller (50) to connect coil drive circuits (26) to a suitable one of a plurality of differing voltage sources (21, 23).

Abstract: A processor (50) is connected to use information supplied by a SCSI controller (32) and a buffer manager (36) to dynamically determines a motion threshold and a reconnect threshold for a buffer memory (56) of a SCSI target device, such as a magnetic tape drive (30). The motion threshold is utilized in comparison with a buffer fill level pointer to determine when transport of the storage media (31) is to be restarted. The reconnect threshold is utilized in comparison with the buffer fill level pointer to determine when the target device can reconnect to the SCSI bus (20).

Abstract: An automated cartridge handling system or library (20, 20') for storing cartridges (22) of information storage media comprises a cartridge holder (26); a tape drive (30) movably mounted with respect to the cartridge holder; and, a transport system (40) for transporting the tape drive (30) in a drive transport path (42) between a unloaded position and a cartridge loaded position. The cartridges (22) remain stationary in the library while the tape drive is transported between the unloaded position and the cartridge loaded position. The cartridge holder library has a plurality of apertures (70) which receive cartridge holders or spines (80). To retain the cartridge (22) within the spine, each spine has resilient cartridge retaining fingers (100) formed in its interior cavity (90) for engaging a notch (104) on the cartridge. Each spine is provided with stabilization flanges (112) for stabilizing the cartridge.

Abstract: Method and apparatus are provided for counteracting tape interlayer slip in a magnetic tape drive (20) which has a swingarm (84) in a tape path between a tape supply reel and a tape take-up reel. So long as an interlayer slip is not detected, a reel motor (30) for the tape supply reel is driven in accordance with a primary strategy related to a position of the swingarm (84). Upon detection of the interlayer slip, the reel motor (30) is driven in accordance with a secondary strategy. In a first embodiment, the secondary strategy depends on the velocity of the reel motor; in a second embodiment, the secondary strategy depends on the velocity of the reel motor and the swingarm average position.

Abstract: An automated cartridge library (30) includes a rotatable spit (100) which has only two mounting surfaces for engaging two respective cartridge magazines (110A, 110B). The library includes a cartridge transport mechanism (80) for selectively engaging cartridges and transporting cartridges between a presented one of the magazines and input/output (I/O) drives (40A, 40B) within the confines of a library housing. The spit (100) has a spit width (SW) which is essentially 0.6 of a smallest dimension (X) of the housing. The spit comprises two tray compartments (130A, 130B), each tray compartment being provided with ribs (144, 154) extending in two dimensions for securing and properly locating its respective magazine. The spit is provided with a magazine latch mechanism (170) which includes biased magazine-capturing protrusions (220A) retained in a pulley member (143).