Patent ID: 6078452
Filing Date: 2000-06-20
Classification: G11B

Abstract:
A method of operating a disk drive having a sampled signal head positioning servo system and a rotating disk with a plurality of data tracks on a surface of the disk, wherein each data track has multiple spaced-apart sequentially-active servo sectors and data regions disposed between the servo sectors, the method comprising the steps of:executing a command to perform a write operation to write a data block to a target data region;encountering a defective servo sector S.sub.n preceding the target data region during the write operation, the defective servo sector S.sub.n preceding a servo sector S.sub.n+1 and following a servo sector S.sub.n-1 ;setting a timer interval to enable a first detection window Dw.sub.n+1 for detecting a field in the servo sector S.sub.n+1 ;if the field is detected within the first detection window Dw.sub.n+1, detecting a field within a detection window Dw.sub.n-1 for the servo sector S.sub.n-1 ;setting a timer interval to enable a detection window Dw.sub.n for detecting a field within the defective servo sector S.sub.n ;after the timing interval has expired without detection of the field within the detection window Dw.sub.n, writing the data block in the target data region following the defective servo sector S.sub.n conditioned on detecting the field within the detection window Dw.sub.n-1 for the servo sector S.sub.n-1 ;setting a timer interval to enable a second detection window Dw.sub.n+1 for detecting a field in the servo sector S.sub.n+1 ; andif the field in the servo sector S.sub.n+1 is detected within the second detection window Dw.sub.n+1, marking the data block as being successfully written.