Recording and/or reproducing apparatus and method of controlling same

• US 5,532,991 A
• Filed: 08/11/1995
• Issued: 07/02/1996
• Est. Priority Date: 04/12/1993
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Sasaki, Yoshio
• Primary Examiner(s): YOUNG, WAYNE R
• Application Number:
  US08/513,721
• Time in Patent Office: 326 Days
• Field of Search: 369/44.26, 369/44.29, 369/44.31, 369/44.32, 369/44.33, 369/44.35, 369/44.36, 369/48, 369/50, 369/54, 369/58, 369/60, 369/32
• US Class Current: 369/44.35
• CPC Class Codes: G11B 7/0941 Methods and circuits for servo gain or phase compensation during operation for initialising servos G11B7/0945
• CPC Class Codes: G11B 7/0946 specially adapted for operation during external perturbations not related to the carrier or servo beam, e.g. vibration
• CPC Class Codes: G11B 7/0948 specially adapted for detection and avoidance or compensation of imperfections on the carrier, e.g. dust, scratches, dropouts G11B7/095 takes precedence

Abstract

A recording and/or reproducing apparatus for recording data on and/or reproducing data from a recording medium includes a recording and/or reproducing unit, a memory, a memory controller, and a servo control circuit, and a system controller. The recording and/or reproducing unit records data on the recording medium and/or reproduces recorded data from the recording medium. The memory temporarily stores data outputted from the recording and/or reproducing unit or input data to be recorded on the recording medium by the recording and/or reproducing unit. The memory controller controls the memory to write and read data such that data are read from the memory in a unit of time at a transfer rate lower than the transfer rate at which data are written in the memory in a unit of time. The servo control circuit supplies a servo control signal to the recording and/or reproducing means, and has an adjustable servo control gain. The system controller temporarily interrupts the recording of data on the recording medium or the reproducing of data from the recording medium with the recording and/or reproducing unit based on the amount of data stored in the memory, and controls the servo control circuit and the recording and/or reproducing unit to automatically adjust the servo control gain while the recording or reproducing of data is temporarily interrupted.

Claims

1. A recording and/or reproducing apparatus comprising:

recording and/or reproducing means for recording data on a recording medium and/or reproducing recorded data from the recording medium;

memory means for temporarily storing data outputted from said recording and/or reproducing means or input data to be recorded on the recording medium by said recording and/or reproducing means;

memory control means for controlling said memory to write and read data such that data are read from said memory means in a unit of time at a transfer rate lower than the transfer rate at which data are written in said memory means in a unit of time;

servo control means for supplying a servo control signal to said recording and/or reproducing means, said servo control means having an adjustable servo control gain; and

system control means for controlling operation of said recording and/or reproducing means, said memory control means, and said servo control means;

wherein the input data are recorded on the recording medium through said memory means and the data reproduced from the recording medium are outputted through said memory means;

said system control means comprising means for temporarily interrupting the recording of data on the recording medium or the reproducing of data .from the recording medium with said recording and/or reproducing means based on the amount of data stored in said memory means, and controlling said servo control means and said recording and/or reproducing means to automatically adjust the servo control gain while the recording or reproducing of data is temporarily interrupted.

2. A recording and/or reproducing apparatus according to claim 1, wherein said servo control means comprises an A/D converter for converting said error signal into a digital signal, a waveform data generator for outputting gain adjusting waveform data, an adder for adding the digital signal outputted from said A/D converter and the gain adjusting waveform data generated by said waveform data generator, a multiplier for multiplying an output signal from said adder by a predetermined coefficient to generate a servo control signal, a filter for extracting the gain adjusting waveform data from the digital signal outputted from said A/D converter, and a comparator for varying said coefficient based on the result of comparison between the gain adjusting waveform data generated by said waveform data generator and an output signal from said filter.

3. A recording and/or reproducing apparatus according to claim 1, the apparatus further comprises temperature detecting means for detecting an ambient temperature, said system control means comprising means for controlling said servo control means and said recording and/or reproducing means to automatically adjust the servo control gain of said servo-control means based on temperature information from said temperature detecting means.

4. A recording and/or reproducing apparatus according to claim 1, wherein said system control means includes timer means for measuring time, said system control means comprising means for controlling said servo control means and said recording and/or reproducing means to automatically adjust the servo control gain of said servo control means based on time information from said timer means.

5. A recording and/or reproducing apparatus according to claim 1, wherein said system control means comprises means for controlling said servo control means and said recording and/or reproducing means to automatically adjust the servo control gain of said servo control means based on address information extracted from the recording medium by said recording and/or reproducing means.