An example of Differential Manchester encoding, representing logical 0 and 1 by the presence and absence of a transition, respectively. At alternating clock tics, indicated by vertical lines, there are either unconditional transitions (for easy clock recovery, full lines) or transitions conditional on the data (dotted lines). The two signals are amplitude-inverted versions of each other both representing the given data; which one is occurring on the line depends on previous data (including the toggling line when idle).
Differential manchester encoding.svg
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