Abstract: An apparatus, system, and method are disclosed for dynamic tape stick and tape break detection. A first counter increments a first count and resets a second count in response to a sensor pulse from a first sensor of a first tape servo. A second counter increments the second count and resets the first count in response to a sensor pulse from a second sensor of a second tape servo. A detection module detects either the first count or the second count exceeding an error threshold.

Abstract: A tape drive system which includes the ability to reliably reproduce LPOS information even if both of the servo channels of the tape drive system could not detect the LPOS information due to defects. The system recognizes that an LPOS sequence is sequentially incremented by one if a tape is moving in a forward direction and decremented by one if the tape is moving in a backward direction. This sequential property of the LPOS information lends itself to LPOS prediction, where the LPOS prediction is the previous LPOS value plus one if the tape is moving forward and the previous LPOS value minus one if the tape is moving backward. Even if the LPOS words from the two servo channels are both bad, but not all of the bits in the LPOS word are bad. The system uses the remaining good bits from the two servo channels to verify all of the bits of the LPOS prediction word.

Abstract: A tape drive and a method of using a tape drive is provided. The tape drive includes a head assembly including at least a first and a second servo read element configured to detect transition stripes of a servo pattern on tape media. The first servo read element is configured to detect at least two transition stripes of an even servo band on the tape media at a first time. The servo detection logic is configured to detect a timing of at least two transition stripes of the even servo band on the tape media. The servo controller is configured to position the head assembly laterally with respect to the tape media in response to the timing of the at least two transition stripes of the even servo band on the tape media. The second servo read element is configured to detect at least two transition stripes of an odd servo band on the tape media at a second time, wherein the second time is a time delay after the first time corresponding to a distance D.

Abstract: An apparatus, system, and method are disclosed for formatting a timing-based servo pattern on a magnetic tape. A first write head concurrently writes a base number of stripes to a plurality of first stripe patterns with a first and third element and writes the base number of stripes to a plurality of second stripe patterns with a second and fourth element of a first write head in response to at least one first write signal. A second write head concurrently writes an incremental number of stripes to a specified first stripe pattern to form a first incremental stripe pattern with a fifth write element and writes the incremental number of stripes to a specified second stripe pattern to form a second incremental stripe pattern with a sixth write element.

Abstract: Selection of servo signals for peak detection of timing based servo tracks of magnetic tape for lateral positioning of heads relative to the magnetic tape. Servo signals from magneto-resistive servo read head(s) reading a magnetic tape are digitized by analog to digital converter(s); digital peak measurement apparatus is configured to sense the digital converter(s), and provide positive peak values and negative peak values of the digitized servo signals; and control apparatus is configured to determine the greater of the provided positive peak values or negative peak values, and select servo signals having the greater values for a servo channel. Servo apparatus is configured to respond to the selected servo signals to control the lateral positioning of the servo read head(s).

Abstract: Provided is a read channel, storage drive, and method to process signals read from a storage medium. At least one data channel including an interpolator and equalizer and a servo channel includes an interpolator. A timing recovery function processes a timing error from the interpolator in the servo channel to calculate interpolation timing information used by the interpolator to interpolate a servo channel signal. A path is coupled to the timing recovery function and the interpolator in the at least one data channel to communicate the interpolation timing information to the interpolator in the at least one data channel. The interpolator in the at least one data channel is configured to use the interpolation timing information to interpolate an asynchronous data channel signal.

Abstract: An apparatus, system, and method are disclosed for checking tape reel motion. A control module directs a leading servo to apply torque to a leading reel and a trailing servo to apply torque to a trailing reel, wherein the control module directs the leading servo to apply an initial positive torque in a tape motion direction and directs the trailing servo to apply an initial negative torque counter to the tape motion direction. If there is no change in an angular position of the leading and trailing reels, the control module incrementally sums a first incremental positive torque to the leading torque to increase the leading torque and a second incremental positive torque to the trailing torque until there is a change in the angular position of the leading and trailing reels and/or until the torques exceed torque limits.

Abstract: An apparatus, system, and method are disclosed for an “M” servo pattern. A servo pattern write module is included to simultaneously create a first servo mark, a second servo mark, a third servo mark, and a fourth servo mark in an “M” servo pattern on a magnetic tape. The magnetic tape is configured to store data. The first, second, third, and fourth servo marks are substantially linear and are substantially the same length. The first and third servo marks are positioned with a forward slope comprising first and third legs of the “M” pattern. The second and fourth servo marks are positioned with a backward slope comprising second and fourth legs of the “M” pattern. Distances between center points of the first and second servo marks, second and third servo marks, and third and fourth servo marks are substantially the same.

Abstract: A storage drive implements a method for a BEMF voltage reduction during a deceleration period of an electric motor of the storage drive. In operation, the electric motor is disconnected from a power supply during an entirety of the deceleration period of the electric motor to prevent any flow of a BEMF current into the power supply, and the electric motor is connected to a power return during a segment or an entirety of the deceleration period of the electric motor to dissipate any BEMF voltage within the electric motor.

Abstract: An apparatus, system, and method are disclosed for formatting a timing-based servo pattern on a magnetic tape. A first write head concurrently writes a base number of stripes to a plurality of first stripe patterns with a first and third element and writes the base number of stripes to a plurality of second stripe patterns with a second and fourth element of a first write head in response to at least one first write signal. A second write head concurrently writes an incremental number of stripes to a specified first stripe pattern to form a first incremental stripe pattern with a fifth write element and writes the incremental number of stripes to a specified second stripe pattern to form a second incremental stripe pattern with a sixth write element.

Abstract: Multiple servo sensors are laterally displaced over a distance less than the transverse width of timing based servo track laterally extending transitions. The servo sensors are configured to sense the transitions, and servo detection logic detects the relative timings of the laterally extending transitions sensed by the laterally displaced servo sensors as the magnetic tape is moved in the longitudinal direction. Logic is configured to determine from the relative timings of the sensed transitions for at least one known set of laterally extending transitions having differing slants, the lateral position of a servo sensor by employing the relative timing detected from one servo sensor and the relative timing detected from another servo sensor, or determine the longitudinal velocity of the magnetic tape by determining the difference between the relative timing detected from one servo sensor and the relative timing detected from another servo sensor.

Abstract: Selection of servo signals for peak detection of timing based servo tracks of magnetic tape for lateral positioning of heads relative to the magnetic tape. Servo signals from magneto-resistive servo read head(s) reading a magnetic tape are digitized by analog to digital converter(s); digital peak measurement apparatus is configured to sense the digital converter(s), and provide positive peak values and negative peak values of the digitized servo signals; and control apparatus is configured to determine the greater of the provided positive peak values or negative peak values, and select servo signals having the greater values for a servo channel. Servo apparatus is configured to respond to the selected servo signals to control the lateral positioning of the servo read head(s).

Abstract: Selection of servo signals for peak detection of timing based servo tracks of magnetic tape for lateral positioning of heads relative to the magnetic tape. Servo signals from magneto-resistive servo read head(s) reading a magnetic tape are digitized by analog to digital converter(s); digital peak measurement apparatus is configured to sense the digital converter(s), and provide positive peak values and negative peak values of the digitized servo signals; and control apparatus is configured to determine the greater of the provided positive peak values or negative peak values, and select servo signals having the greater values for a servo channel. Servo apparatus is configured to respond to the selected servo signals to control the lateral positioning of the servo read head(s).

Abstract: Disclosed are a system, a method, and an article of manufacture to provide for the detection and compensation of tape breakage in a tape drive. The invention operates by simultaneously monitoring the tape reel rotation direction and the ratio of rotation between the tape reels. If the rotation direction is not the same for both reels, then tape breakage is indicated and reel rotation ceases. Tape breakage is also detected if the tape reel angular rotation ratio between the supply and take up reels is not within a specified tape reel ratio range. The tape reel angular rotation ratio is detected by simultaneously measuring the angular rotation of each tape reel in a specified time period and then calculating the ratio. The present invention detects the tape reel angular rotation ratio and if tape reel angular rotation ratio is outside of the specified tape reel ratio range, tape breakage is indicated and reel rotation ceases.

Abstract: Multiple servo sensors are laterally displaced over a distance less than the transverse width of timing based servo track laterally extending transitions. The servo sensors are configured to sense the transitions, and servo detection logic detects the relative timings of the laterally extending transitions sensed by the laterally displaced servo sensors as the magnetic tape is moved in the longitudinal direction. Logic is configured to determine from the relative timings of the sensed transitions for at least one known set of laterally extending transitions having differing slants, the lateral position of a servo sensor by employing the relative timing detected from one servo sensor and the relative timing detected from another servo sensor, or determine the longitudinal velocity of the magnetic tape by determining the difference between the relative timing detected from one servo sensor and the relative timing detected from another servo sensor.

Abstract: An apparatus, system, and method are disclosed for detecting a periodic sequence. A value detector module detects a plurality of values of a periodic sequence. In one embodiment, a transformation module transforms the plurality of values into transformed values. A confinement module confines the values to a limited set of confined values. A correlation module correlates the confined values with a plurality of instances of the periodic sequence. In addition, a selection module selects an instance of the periodic sequence with the highest correlation to the confined values as an observed periodic sequence.

Abstract: An apparatus, system, and method are disclosed for the velocity proportional clocking of time base servo tape storage devices. The apparatus, system, and method allow the velocity of time base servo tape storage devices to be adjusted and maintained by adjusting the frequency of a clock. In one embodiment, a velocity command is received and the clock signal frequency is varied in response to the command. A feedback control signal may then be produced to control the velocity of a time base servo device in response to the clock signal frequency, the feedback control signal being used to vary the velocity of a servo motor. In one embodiment, the velocity of the servo motor varies directly proportionate to the clock signal frequency.

Abstract: Disclosed are a system, a method, and an article of manufacture to provide for the detection and compensation of tape breakage in a tape drive. The invention operates by simultaneously monitoring the tape reel rotation direction and the ratio of rotation between the tape reels. If the rotation direction is not the same for both reels, then tape breakage is indicated and reel rotation ceases. Tape breakage is also detected if the tape reel angular rotation ratio between the supply and take up reels is not within a specified tape reel ratio range. The tape reel angular rotation ratio is detected by simultaneously measuring the angular rotation of each tape reel in a specified time period and then calculating the ratio. The present invention detects the tape reel angular rotation ratio and if tape reel angular rotation ratio is outside of the specified tape reel ratio range, tape breakage is indicated and reel rotation ceases.

Abstract: In a tape having separate servo bands of patterns positioned laterally across the tape, the patterns of a separate servo band have at least one differentiating characteristic with respect to patterns of another of the separate servo bands. The differentiating characteristic allows identification of the separate servo bands. For example, the patterns of a separate servo band have differing azimuthal orientations of detectable transitions with respect to another servo band, such as being laterally inverted. In another, variations in the width of gaps of patterns are made with respect to another servo band. In another, variations are made in the number of the detectable transitions of patterns with respect to the patterns of another servo band.

Abstract: In a tape having separate servo bands of patterns positioned laterally across the tape, the patterns of a separate servo band have at least one differentiating characteristic with respect to patterns of another of the separate servo bands. The differentiating characteristic allows identification of the separate servo bands. For example, the patterns of a separate servo band have differing azimuthal orientations of detectable transitions with respect to another servo band, such as being laterally inverted. In another, variations in the width of gaps of patterns are made with respect to another servo band. In another, variations are made in the number of the detectable transitions of patterns with respect to the patterns of another servo band.