Method and apparatus for controlling renewal of data in optical disc memory

An apparatus for controlling the reading and writing of data in an optical disc memory, comprising:

• an erasable optical disc memory having a recording region for recording data and a directory region recording direction data for controlling the content of the data written in said recording region, for which record and erase cannot be effected simultaneously;
• head means for recording, reproducing and erasing said data and directory data on said optical disc memory;
• external directory memory means for storing said directory data with the same format as that of the directory data in said directory region on said optical disc memory;
• and
• control means connected with said external directory memory means and said head means for controlling write, read and erase operations of said head means using the directory data stored in said external directory memory means.

A method for controlling renewal of data in an optical disc memory comprising:

• (1) writing new recording data in a region where the write operation has not yet been effected or where an erase operation has already been effected;
• (2) effecting an erase operation while the optical disc memory is not accessed;
• (3) transferring the directory data in a directory region on said optical disc memory to an external directory memory when the power is turned on or when a new disc medium is loaded;
• and
• (4) transferring said directory data on said external directory memory to said directory region on said optical disc memory.

An apparatus for controlling renewal of data in an optical disc memory comprising:

• (1) means for controlling a laser beam for write, read and erase operations;
• (2) an external directory memory by which the read, write and erase operations are controlled;
• (3) means for transferring the directory data from the directory region in an optical disc medium to said external directory memory;
• (4) means for transferring said directory data from said external directory memory to said optical disc medium;
• and
• (5) means for effecting an erase operation while said optical disc memory is not accessed.