 Modified Frequency Modulation - Coding: Encyclopedia II - Modified Frequency Modulation - CodingNotice that two "ones" can't appear together, and the maximum number of zeros in a row is three. This bit stream is then NRZI encoded to be written to disk, a 1 bit representing a magnetic transition, and a 0 bit no transition.
Example:
1 0 1 0 0 0 0 1 ($A1)
0100010010101001 ($44A9)
0100010010001001 ($4489 - sync mark)
^ missing clock
Hexadecimal 4489 is typically used as a unique synchronization mark.
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