Standards/ISO11898-CAN
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Revision as of 18:35, 20 November 2014 by Oliver.gubler (Talk | contribs)
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CAN is a multi-master serial bus. All nodes on the network have to be synchronized to sample or transmit the same bit of a message at the same time. The logical levels are achieved by a pull-up structure. Therefore the idle state of the bus is a logical '1'. Any node transmitting a logical '0' will pull the bus to another level.
Arbitration is achieved by using this bus condition. All nodes start by transmitting their UID and sample the bus at the same time. As soon as they discover that there is another bit on the bus as they are transmitting, they stop the transimission. Finally only the node with the lowest ID will be left an can transmitt it's message undisturbed. ll
