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Is CAN (Controller Area Network) half duplex or full duplex communication? And what is the rationale why?

Is there an ISO CAN document which would clear up my confusion?

Lundin
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Prince
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  • It is half duplex. The rationale is CAN's bus arbitration which determines message priority, without collisions. For this to work, there can only be one active transmitter at a time and others who attempt to send but have lower priority will gracefully back off. ISO documents won't be helpful here, find some reliable beginner tutorial about CAN instead, like this one: https://www.can-cia.org/can-knowledge/ – Lundin Oct 22 '19 at 14:06

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CAN has a single sender with priority arbitration. If two or more nodes attempt to send simultaneously, any nodes transmitting a lower priority ID will stop transmitting during the arbitration phase.

If your definition of "full duplex" is two transmitters able to send a message concurrently, then CAN does not meet that definition.

janm
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