CAN bus: Difference between revisions
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** This dominant signal is considered the "start bit" of frame | ** This dominant signal is considered the "start bit" of frame | ||
* Resynchronization occurs on each subsequent recessive to dominant transition | * Resynchronization occurs on each subsequent recessive to dominant transition | ||
==Signaling== | |||
A CAN bit, signaled using [https://en.wikipedia.org/wiki/Non-return-to-zero NRZ coding] is made up of at least four quanta | |||
* Synchronization segment (it is here that the bit edge takes place) | |||
* Propagation segment compensating for delay in bus lines | |||
* Phase Segment I | |||
* Phase Segment II | |||
The Synchronization segment's transition is a "hard synchronization" -- it defines the bit starttime. Resynchronization takes place during the Phase Segments, which are lenghtened or shortened based on a phase error relative to the synchronization segment (up to the configured Synchronization Jump Width). Sampling typically takes place between the two Phase Segments, with "triple-sampling" interfaces taking the majority-decode of three samples across the bit. | |||
The total length is referred to as the Nominal Bit Time. | |||
==Frames== | ==Frames== | ||