On 16.02.2021 09:44:54, Torin Cooper-Bennun wrote:

quoted

Your mram-cfg looks broken, You don't have any TX Event FIFO entries. Please use
this one:

bosch,mram-cfg = <0x0 0 0 16 0 0 1 1>;

Okay, thanks for the tip, I usually don't make use of the TX event
feature!

You might not, but the driver does :)

This hasn't fixed the TX behaviour, though. I've verified
that the frame is loaded into MRAM and requested for TX correctly, but
the transceiver does this...

1. sends start-of-frame, then 5 bits of ID correctly, at the correct bitrate
2. bus then seems to be stuck dominant for 6 bits instead of
transmitting further ID bits
3. bus lines drift back recessive (not a clean edge) over the duration
of 12 bits
4. process repeats

Steps 2-3 constitute an error frame, if my understanding is correct.
Presently the TCAN4550 is not connected to any other CAN nodes; I
would therefore expect the transmit to at least continue to the ACK
field.

If the process repeats infinitely then the CAN controller doesn't go
into bus-off, which means the CAN bus is terminated correctly.

With your setup of only one node on the bus and correct termination, I
too think the frame should be send until the ACK field. I suggest to
first create a working CAN bus setup and then add the tcan to it.

regards,
Marc

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