CAN/CAN-FD, Oscillator

Can Beaglebone Black (or any derivative with expansion board) read/write to CAN/CAN-FD bus? If yes, does it need expansion board?

Can the Beaglebone Black (or any derivative with expansion board) function as a grand-master clock in the network? What is the accuracy of the on-board oscillator? If not, can the same be implemented through the expansion board?

The stock BeagleBone Black cannot do CAN_FD.

Master Clock accuracy question requires more information.

Is it Time of Day or just periodic?

If it’s time of Day then is it connected to the network because then you can get a fairly accurate time from the NTP servers.

Periodic accuracy will depend more on High Level Protocol (HLP) than absolute time. For example MilCAN is designed to create a periodic heart beat with no jitter and helps synchronize other devices. Other HLPs can have a time message delayed by one full network message.

John

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You need CAN transceivers to use a BeagleBone Black for CAN stuff. Any cape marked for CAN will do, but I’d probably get the " BeagleBoard.org BeagleBone Comms Cape" as it is likely to have something approaching “support”.

As for grand-master clock, CAN clients specifically adjust to match up to baud rates that are slightly off or drifting. The fact that you asked this question makes me suspicious that you are using something “higher level” than straight CAN/CAN-FD. If that’s true, your question can only be answered by understanding the limitations of the higher protocol stack.