Carrier Sense Multiple Access / Collision Resolution

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Carrier Sense Multiple Access / Collision Resolution (CSMA / CR) is a process that is used to detect and resolve collisions on shared media. It is used in field buses such as the Controller Area Network (CAN).

With CSMA / CR, collisions are recognized by bit arbitration . This ensures that at the end of each arbitration phase, only the participant who has the highest message priority occupies the medium. Collisions are recognized by participants with a lower priority and cause these participants to withdraw from the channel. The collisions have no influence on the message of the participant with the highest priority, so that this message can be sent without delay.


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