====== Sync (aka Mark) ======

Special marker used to separate different areas of data.

The sync is (in theory) not produced by the [[glossary:encoding]] used on a data area. Therefore it can mark the beginning (sometimes not really the beginning) of a new physical/logical data area, known as a [[glossary:block]]. The PC and the Commodore Amiga's "AmigaDOS" [[glossary:custom disk format|format]] both use [[glossary:MFM]] "0x4489" as the sync pattern, however it is possible for custom Amiga formats to have many different sync values on the very same [[glossary:track]].

In the [[glossary:cta|analyser]] it is referred to as the "Mark" to be more in line with [[glossary:trace_machine|Trace]] conventions. It is treated as data, but the encoding can be modified, but it is used by the analyser to spot areas on a track in the first place.