NRZI

E96090

NRZI (Non-Return-to-Zero Inverted) is a digital line coding scheme that represents binary data by inverting the signal level on a '1' and leaving it unchanged on a '0', commonly used in various networking and storage technologies.


Statements (48)
Predicate Object
instanceOf digital encoding scheme
line code
advantage improves clock recovery when data has sufficient ones density
reduces DC component compared to NRZ-L for random data
robust against polarity inversion of the physical medium
alsoKnownAs NRZ-I
Non-Return-to-Zero Invert-on-ones
applicationDomain computer storage
data communications
telecommunications
belongsToClass non-return-to-zero codes
bitRepresentation logical 0 leaves current signal state unchanged
logical 1 causes inversion of current signal state
category physical layer coding
dependsOn signal transitions rather than absolute levels
disadvantage long runs of zeros produce no transitions
requires additional mechanisms to ensure sufficient transitions
encodingRule a binary 0 is represented by no transition of the signal level
a binary 1 is represented by a transition of the signal level
fullName Non-Return-to-Zero Inverted
goal efficient binary data transmission over physical media
improve timing recovery compared to simple NRZ level coding
hasProperty self-clocking only if data pattern has enough ones
transition occurs at bit boundaries only
two possible signal levels
isDifferential true
relatedTo Manchester code
NRZ-L
RLL (run-length limited) codes
biphase mark code
requires bit stuffing or run-length limiting for long sequences without transitions
signalProperty signal level does not return to a zero baseline between bits
standardizedIn USB 2.0 specification
various magnetic recording standards
usedIn HDLC-like protocols with bit stuffing
High-Speed USB with bit stuffing
SCSI parallel interfaces (legacy)
USB 1.x
USB 2.0 full-speed
USB 2.0 low-speed
fiber channel variants (as a component of higher-level coding)
magnetic tape recording
older floppy disk formats
optical communication systems
serial communication links
usedWith bipolar signaling
differential signaling
unipolar signaling

Referenced by (3)
Subject (surface form when different) Predicate
NRZI ("Non-Return-to-Zero Invert-on-ones")
alsoKnownAs
NRZI ("Non-Return-to-Zero Inverted")
fullName
100BASE-FX
usesLineCode

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