topic Re: Setting the transmissing priority of the FlexCAN module in S32K

Setting the transmissing priority of the FlexCAN module

SONGTAOSI — Mon, 27 Feb 2023 09:17:16 GMT

Hi,

I have a poor understanding of the FlexCAN module sending priority, can you provide a Demo about sending priority setting.

Thanks.

Re: Setting the transmissing priority of the FlexCAN module

PetrS — Mon, 27 Feb 2023 12:53:53 GMT

Hi,

please refer to chapter 55.3.3 Arbitration process of the RM for the explanation of transmitting priority.
During arbitration process the TX MB winner is selected using below mechanisms depending on CTRL1[LBUF] and MCR[LPRIOEN] setting.
- Lowest-number mailbox first or
- Highest-priority mailbox first

For example the SDK has no support/option to configure that, CTRL1[LBUF] is keeping cleared, I think.

BR, Petr

Re: Setting the transmissing priority of the FlexCAN module

SONGTAOSI — Tue, 28 Feb 2023 01:31:33 GMT

Hi,

Thank you for your answer.

I have another question. How can I send multiple messages at the same time.

Re: Setting the transmissing priority of the FlexCAN module

PetrS — Tue, 28 Feb 2023 09:09:25 GMT

Hi,

there is single CAN message at a time on the CAN bus.
You can prepare as many TX MB for sending as you need, and those will be sent one after another according the internal arbitration and the bus arbitration as well.

BR, Petr