On 26.02.2021 13:45:22, Torin Cooper-Bennun wrote:
> > Can you give me a reference to this?
> 
> Here's the manual for 3.3 (annoyingly, I can't find corresponding
> documents for earlier M_CAN versions, and TCAN4550 uses 3.2...)

https://github.com/hartkopp/M_CAN-User-Manual-History

> http://www.bosch-semiconductors.com/media/ip_modules/pdf_2/m_can/mcan_users_manual_v330.pdf
> 
> See Section 2.3.9, "Timestamp Counter Configuration (TSCC)". Quote:
> 
>     Note: With CAN FD an external counter is required for timestamp
>     generation (TSS = “10”)

I suggest to check on the tcan hardware, what's really in the register.

Marc 

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