Concepts
USB Signaling
•USB uses Non-Return to Zero, Inverted signaling
–Separate clock signal not required to be delivered with data
–‘1’ on the data line indicates no change in level of NRZI signal
–‘0’ on the data line indicates transition in level of NRZI signal
–Long string of 1s will eventually cause receiver to lose
General
synchronization
TM
Software –
Idle | 0 | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 0 |
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Data
NRZI
