address mark

Quick Reference

The special code on a magnetic disk track that occurs just prior to the address information of a sector. In the case of an MFM drive (see disk format), the encoding rules for MFM are broken so that the code is unique. The purpose of the address mark is to bring the drive control electronics into byte synchronization with the header data.

The data mark fulfills the same function with respect to data as the address mark to the address.

Subjects: Computing.

Reference entries