Pickup position control method enabling restart of reproduction after interruption

Claim 2

A pickup position control method for a disk reproducing device, comprising the steps of when the power supply is interrupted during reproduction: holding a pickup for reading data recorded on a disk-shaped recording medium at the last reading position of said recording medium; reading by said pickup data recorded on said disk-shaped recording medium on said last reading position when said power supply is resupplied to said disk reproducing device; generating target address data according to read address data in said read recorded data, said target address data having a predetermined, non-identical relationship to said read address data; moving said pickup according to an address difference between said target address data and said read address data to a position indicated by said target address data; and beginning reproduction from said position indicated by said target address data.

Claim 3

A method as recited in claim 1, wherein said data recorded on said disk-shaped recording medium is divided into divisions of unequal time duration and said position indicated by said target address data is at a starting position of the division containing the position indicated by said read address data.

Claim 4

A method as recited in claim 2, wherein said division are tracks.

Claim 5

A pickup position controller, comprising: a pickup for detecting signals recorded on a disk-shaped recording medium; means for moving said pickup radially of said disk-shaped recording medium; means for extracting from said detected signal address data indicating a location of said pickup relative to said recording medium; means for controlling said moving means according to said extracted address data, wherein said controlling means causes said moving means to hold stationary said pickup at an interruption position during an interruption of power to said controller; wherein said controlling means after a supply of power to said controller following said interruption causes said extracting means to extract first address data indicating said interruption position and further includes means for calculating second address data having a predetermined, non-identical relationship to said first address data and means for causing said moving means to move said pickup to a position indicated by said second address data.

Claim 6

A pickup position controller, comprising: a pickup for detecting signals recorded on a disk-shaped recording medium; means for moving said pickup radially of said disk-shaped recording medium; means for extracting from said detected signal address data indicating a location of said pickup relative to said recording medium; means for controlling said moving means according to said extracted address data, wherein said controlling means causes said moving means to hold stationary said pickup at an interruption position during an interruption of power to said controller; wherein said controlling means after a supply of power to said controller following said interruption causes said extracting means to extract first address data indicating said interruption position and further includes means for calculating second address data having a predetermined, non-identical relationship to said first address data and means for causing said moving means to move said pickup to a position indicated by said second address data.

Claim 7

A controller as recited in claim 4, wherein said data recorded on said disk-shaped recording medium is divided into divisions of unequal time duration and said position indicated by said second address data is a starting position of the division containing the position indicated by said first address data.