Patents Examined by Christopher Onuaru
  • Patent number: 6246829
    Abstract: A recording medium includes a user data area (UDA) for writing real data and a program memory area (PMA) for writing management data. In the PMA, a repetitive writing operation number NA of the UDA, write end address AE, operation life number NL and final address AL, etc. are written. On the occasion of recording real data to the UDA, writing is started from the address next to the write end address AE at the time of the preceding recording operation and after the recording is executed up to the final address AL, data writing is started again from the start address to give an increment of one (1) to NA. The real data is written in average up to the final address from the start address of UDA. When NA exceeds NL, a warning is displayed and the recording medium (e.g. a disc) ejected. Therefore, the recording medium's operational life is extended and the safety of data written to the UDA is assured.
    Type: Grant
    Filed: April 9, 1998
    Date of Patent: June 12, 2001
    Assignee: Sony Corporation
    Inventor: Kenzo Nakagawa