Patent ID: 6714719
Filing Date: 2004-03-30
Classification: G11B,H04N

Abstract:
In a magnetic disk drive which drives a magnetic head to record or reproduce video information at a predetermined position on a magnetic disk in response to a command being given from a host machine, said magnetic disk drive comprising:reassignment process decision means for if a defect sector appears on the magnetic disk, making a decision as to whether a reassignment process, in which data to be recorded on the defect sector is assigned to and recorded on an alternate sector, is performed immediately or not; and calibration decision means for making a decision, based on time information being read from the host machine, as to whether a calibration is performed or not, wherein a time margin is calculated with reference to capacity of a buffer memory, a maximum transfer speed and a data transfer speed by which recording signals are transferred onto the magnetic disk, so that the reassignment process decision means makes the decision whether to perform the reassignment process immediately by comparing the time margin with a time required for execution of the reassignment process.