Magnetic media certification

A system for certifying that a track on a magnetic tape is defective comprising:

• a tape head for accessing the tape, the tape head comprising a read module following a write module in a direction of tape travel past the tape head, the write module operative to simultaneously write at least one data track on the tape, the read module operative to simultaneously read at least one data track on the tape;
• a write formatter in communication with the write module, the write formatter operative to write a sequence of defect matrices onto at least one data track, the number of defect matrices in the sequence based on a determined defect length;
• a read formatter in communication with the read module, the read formatter operative to
• a) read each defect matrix,
• b) detect an error in data read from the defect matrix,
• c) determine if the defect matrix contains a defect based on error detection, and
• d) determine the defect length based on defect matrices in the sequence of defect matrices determined to have a defect.

A system for certifying that a track of magnetic media is defective, the track accessed by a head having a read module following a write module in a direction of media travel past the head, the write module operative to simultaneously write at least one data track on the media, the read module operative to simultaneously read at least one data track on the media, the system comprising:

• means for detecting the start of a defect;
• means for writing a sequence of defect matrices over the defect with a write element in the write module;
• means for reading each defect matrix in the sequence of defect matrices with a read element in the read module;
• means for determining if an error exists in data read from each defect matrix;
• and
• means for determining that the defect extends through each defect matrix if an error exists in the read data.