Browse Prior Art Database

Fault-Tolerant Sync Byte for Run-Length-Limited Codes

IP.com Disclosure Number: IPCOM000060975D
Original Publication Date: 1986-Jun-01
Included in the Prior Art Database: 2005-Mar-09

Publishing Venue

IBM

Related People

Authors:
Bliss, WG Cunningham, EA [+details]

Abstract

Data fields in magnetic recording are preceded by a "sync field" used to synchronize a phase-locked oscillator during readback. A special sync byte at the end of the sync field marks the start of data. Since the sync field, and especially the sync byte, are susceptible to errors which are not corrected by the data error correction code (ECC), there is a significant probability of loss of data due to errors in the sync area. This results in a failure to identify the sync byte or a failure by false detection at a time earlier than the proper time. This is especially true where higher density magnetic recordings, allowed by the use and dependence on ECC, puts even more stress on regions not covered by ECC. A system is therefore required to protect the sync area similar to the ECC protection of data.