Fujitsu Corporation

Fumiaki Uematsu

Masaru Sawada

Koji Horibe

Hideaki Tanishima

Tsunehiko Moriuchi

Kenichi Yamakura

Manabu Nakano

Tsuyoshi Tomita

Yoshitaka Nakata

A signal processor used to process an analog read signal representing data stored on a magnetic disk allows for a faster read operation without requiring an increase in its circuit area or buffer memory space. The signal processor includes a decision feedback equalizer which selectively provides a feedback signal added to a read signal in reproducing data read from a storage medium. The signal processor also performs error correction. In performing error correction, the load of the error correcting process is detected and the processing speed is altered depending upon the detected load.

Signal processor having feedback loop control for decision feedback equalizer

A digital video disk controller for reading data from an optical disk and stores the data in a memory. The data is then read from the memory and encrypted by an arithmetic processor. The encrypted data is then transmitted directly to an external device, via an interface circuit, without first storing the encrypted data back into the memory. The number of memory accesses performed by the controller is thus reduced, providing for lower power dissipation and faster access to the read data.

Method of reading, encrypting and transferring data

Growing community of inventors

Kasugai, Japan

Fumiaki Uematsu