Patent ID: 6751174
Filing Date: 2004-06-15
Classification: G11B

Abstract:
A disc playback system comprising:a pickup for reading first information data recorded on an information disc on which data are recorded at a constant linear velocity, from the information disc; a disc motor for rotating the information disc; a digital signal processing circuit for digitizing the first information data according to a playback format of the information disc; an interface control circuit for transmitting second information data which are the data digitized by the digital signal processing circuit, to an external device; a buffer memory for temporarily containing the second information data which are requested by the external device via the interface control circuit; a linear velocity detection means for detecting a linear velocity of the information disc; and a track pitch detection means for detecting a track pitch of the information disc, said disc playback system deciding a reference value for controlling a velocity of the disc motor, on the basis of the linear velocity detected by the linear velocity detection means, the track pitch detected by the track pitch detection means, and a value of a maximum radius of a record area of data which are recorded on the information disc.