Disc recording/reproduction apparatus and method for resetting an address control circuit to maximize an address margin of the memory

A recording/reproduction method for recording and reproducing data onto and from a disc on which control information is written in advance, comprising the steps of:

• controlling, based on the control information taken from the disc, a spindle servo circuit of a spindle motor that
• drives the disc;
• generating a write address of a memory to and from which reproduction digital data is written and read by counting clocks synchronized with the reproduction digital data by a first counter, and a read address of the memory by counting reference clocks by a second counter;
• correcting jitters by producing jitter-removed reproduction digital data from the memory;
• and
• resetting the address control so as to maximize an address margin of the memory when the spindle servo circuit changes from an unlocked state to a locked state.

A disc recording/reproducing apparatus for recording or reproducing data onto or from a disc on which address information is recorded in advance, comprising:

• reproducing means for reproducing signals recorded on the disc as a reproduced signal;
• address information extraction means for extracting the address information from the reproduced signal;
• clock extraction means for extracting a clock component from the reproduced signal;
• memory means for temporarily storing the reproduced signal;
• spindle servo means for controlling a rotation speed of the disc in accordance with the extracted address information;
• reference clock generating means for generating a reference clock;
• memory control means for controlling a write address to the memory means and a read address from the memory means, and including
• counter means for counting the extracted clock component from the clock extraction means;
• address generating means for generating a write address to the memory means in accordance with the extracted clock components counted by the counter means and a read address of the memory means in accordance with the reference clock;
• and
• reset means for resetting the counter means so as to maximize an address margin of the memory means when the spindle servo means changes from an unlocked state to a locked state.

A disc recording/reproduction apparatus for recording and reproducing data onto and from a disc on which control information is written in advance, comprising:

• a spindle servo circuit for controlling, based on the control information taken from the disc, rotation of a spindle motor that drives the disc;
• a memory to and from which reproduction digital data is written and read;
• an address control circuit for generating a write address of the memory by counting clocks synchronized with the reproduction digital data by a first counter, and for generating a read address of the memory by counting reference clocks by a second counter;
• a jitter correction circuit for producing jitter-removed reproduction digital data from the memory;
• and
• reset means for resetting the address control circuit so that the write address of the memory and the read address of the memory are reset to a same value so as to maximize an address margin of the memory when the spindle servo circuit changes from an unlocked state to a locked state.