Non Return to Zero
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Revision as of 11:08, 10 May 2020 by Jnc (talk | contribs) (Jnc moved page NRZ to Non Return to Zero: Full name)
Non Return to Zero (usually given as the acronym, NRZ) is an encoding technique which is commonly used on magnetic storage.
In NRZ, whether a particular bit is '0' or '1' is indicated by the signal level during each clock time; in other words, there is no 'rest' state between bits.
The disadvantage of NRZ is that a long strings of either value do not cause any level transitions (hence the name), so a separate clock is always needed, because it cannot be self-clocking (unless used with either bit stuffing or run-length limited coding, to limit the maximum number of transition-less bit times).
