Dphi Acquisitions, Inc.

Dphi Acquistions, Inc.

Christopher J Turner

Ron Kadlec

Charles R Watt

Hans Brandon Wach

Michael B Propps

Mike Propps

A multi-zone calibration system is disclosed. The multi-zone calibration system calibrates the operating parameters of an optical disk drive over a plurality of zones over an optical media. The optical media, in addition, can have writeable and premastered portions. The operating parameters can be calibrated for each of the media types in each of the zones. Additionally, the operating parameters can be calibrated for each type of operation (e.g., read or write) in each zone.

Digital focus and tracking servo system with multi-zone calibration

A servo system with in an optical disk drive with an inverse non-linearity compensation is disclosed. An error signal calculated from signals received from an optical pick-up unit can be offset by an offset value and amplified by a gain in the early stages of a calculation of a control signal for controlling a position of the optical pick-up unit. The non-linearity compensation adjusts the gain based on the offset value so that the response of the servo system to changes in the error signal is substantially linear. The error signal can be the tracking error signal in a tracking servo system and can be the focus error signal in a focus servo system.

Digital servo system with inverse non-linearity compensation

A focus servo system with a focus close algorithm is disclosed. The focus close algorithm provides a bias control effort to the focus servo system when focus is closed. A method of closing focus includes positioning an optical pick-up unit at a first position away from an optical medium, moving the optical pick-up unit towards a second position by altering a focus control effort, monitoring a sum signal obtained from signals received from the optical pick-up unit, and setting the bias control effort to the focus control effort when a closure criteria is satisfied. In some embodiments, the closure criteria includes that a sum signal exceeds a threshold value. In some embodiments, the closure criteria includes that a focus error signal is below a FES threshold.

Close focus algorithm in a digital focus servo system

An off-format condition in a digital tracking servo is presented. An off-format condition can be detected by low pass filtering a tracking control signal, detecting a DC level over a threshold level, and indicating the off-format condition if the DC level is above the threshold level for a maximum number of cycles.

Digital tracking servo system with off-format detection

A calibration of a focus error signal gain in a focus servo system of an optical disk drive is presented. The focus error signal gain can be calibrated by oscillating an optical pick-up unit in a focus direction through a focus point and determining a focus sum threshold. The optical pick-up unit can then be oscillated around a focus control effort that results in a sum signal equal to the focus sum threshold and the peak-to-peak value of a focus error signal can be measured. The focus error signal gain can be determined from the peak-to-peak value of the focus error signal.

Calibration of a focus error signal gain in a focus servo system

A method of storing calibrated optical parameters is presented. In some embodiments, calibrated optical parameters are stored in place of stored parameters. In some embodiments, averages between the calibrated operating parameters and stored optical parameters are stored. In other embodiments, the stored optical parameters are allowed to vary only by a maximum amount. In some embodiments, if the calibrated parameters vary by more than threshold values, then the calibrated parameters are not stored.

Calibration storage methods for a digital focus and tracking servo system with calibration

An optical disc drive waits to receive a command to perform a function on optical media in the disc drive. The optical media includes a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten. Once a command is received, one portion of the disc drive processes the command while another portion of the disc drive monitors the processing of the command and waits until the command is processed. If an error condition is detected while processing the command, the disc drive generates an event request such as a notify event request, a focus event request, a spin event request, and a tracking event request. When an event issues, the disc drive interrupts processing of the command and attempts to recover from the error condition. The state of the disc drive when the requested event was received is saved before attempting to recover from the error condition. If the recovery attempt is successful, the saved state of the disc drive is restored, and the interrupted command continues to be processed at the point where the interruption occurred. A command finished event is issued when the command is complete. If the recovery attempt was not successful, the interrupted command is replaced with a servo abort command to terminate the interrupted command.

System and method for handling commands in an optical disc drive

A disc drive includes a tracking actuator, and determines when the tracking actuator is positioned off a formatted portion of optical media in the disc drive. The optical media includes a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten. Tracking control effort is monitored to determine when the tracking actuator is in the off-format condition and whether tracking good or tracking bad is detected within a predetermined time period. An absolute value of the tracking control effort is generated and the absolute value of the tracking control effort is filtered. An off-format condition is indicated if the filtered value of the tracking control effort is not within a predetermined threshold value.

System and method for detecting and recovering from an off-format state in an optical disc drive

A write abort algorithm of a tracking and focus servo system that can abort a write operation on an optical disk drive is presented. The write abort algorithm monitors at least one of a tracking error signal or a focus error signal and indicates a write abort status when the tracking error signal or the focus error signal indicates a threshold value. In some embodiments, the write abort algorithms suspends indication of the write abort status in the presence of a defect, suspension of the write abort status occurs more than a predetermined number of times.

Tracking and focus digital servo system with write abort

A focus error signal offset calibration is presented. The focus error signal offset can be calibrated by varying the focus error signal offset to optimize an operating characteristic of the optical disk drive. In some embodiments, the operating characteristic can be a servo function. In some embodiments, the operating characteristics can be a read function.

Calibration of focus error signal offset in a focus servo system

A system and method for controlling operation of a motor system that addresses the design challenges for the small form factor optical disk system. The present invention includes starting the operation of a motor including windings and a rotor; placing the motor in a first operational state; driving the motor from the first operational state to a second operational state; and sensing a variation in an electrical waveform induced by driving of the motor to determine a cycle period from which the speed of the motor can be determined.

System and method for performing a spin motor startup operation

A system and method for controlling operation of a motor system that addresses the design challenges for the small form factor optical disk system. The control system can be operable to read a physical sector address (PSA) from an optical medium, calculate a table index based on the PSA, enter a lookup table module to acquire reference data, and maintain a constant data rate transfer from the optical medium for a range of PSAs.

CLV system and method using PSA lookup

A control system for controlling tracking and seeking in an optical disc drive for optical media with a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten. The control system determines whether an optical pickup unit is over the premastered or the writeable areas of the optical media by measuring peak to peak amplitude of a tracking error signal. Gains and calibration values are selected based on whether an optical pickup unit is over the premastered or the writeable areas of the optical media. Reading from and writing to the optical media is disabled while jumping tracks. Control of jumping tracks on the optical media includes controlling: jumping a single track on the optical media; jumping a specified number of tracks every specified number of revolutions of the optical media; auto jumpbacks, and jumping in forward or reverse directions. Parameters for controlling jumps include at least one of: jump type, number of tracks to jump, time delay between track jumps, number of revolutions of the optical media between jumps, and whether it is not safe to read from or write to the optical media. The control system performs long seeks by predicting whether the tracking actuator arm will be positioned over the premastered area or the writeable area at the end of the long seek, and to load calibration parameters corresponding to the type of media over which the tracking actuator arm will be positioned at the end of the long seek.

System and method for controlling tracking and seeking in an optical disc drive

A system for controlling focus in an optical disc drive for optical media with a premastered area that cannot be overwritten and a user-writeable area that can be overwritten includes instructions for turning focus on and off; and for acquiring focus on the optical media in response to a command to acquire focus. The actuator arm is moved according to a sinusoidal ramp function to prevent exciting resonances in the actuator arm. The amount of push-away force used while moving the actuator arm can be adjusted to avoid overshoot. The integrity of a focus error signal is determined and an attempt to re-acquire focus is made if the focus error signal indicates a bad focus status. The system turns focus off when at least one of the following conditions are met: (1) current state is a ramp focus acquire state and the maximum ramp position was reached; (2) current state is a focus push retry state and best push away value is greater than or equal to a predetermined fraction of a nominal push away value; or (3) a focus problem develops while in a focus active state.

System and method for controlling focus in an optical disc drive

A system, method, and apparatus for coordinating tasks in a control system for an optical disc drive for optical media with a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten. The optical disc drive includes a first processor operable to communicate with a second processor, wherein the first processor includes instructions for performing non-time-critical tasks, and the second processor includes instructions for performing time-critical tasks, such as reading from and writing to optical media in the disc drive. The first processor monitors the status of the time critical tasks in the second processor and transmits commands to perform operations in the second processor. The first processor also controls power mode, manages recovery from errors, controls focus, tracking/seeking, spin, physical sector address (PSA), a laser, adjusts gains, and monitor cartridge load/eject. The first processor can be used to perform other tasks while it is waiting to receive a notice of a new command, a notify event, or a performance event.

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Niwot, CO, United States of America

Christopher J Turner