Can't get FDCAN working on STM32H70-DK

[mhuar.1]

STM32H70-DK FDCAN

Hello everyone:

I want to use FDCAN in my board but it is not working.

I've been using a few examples I've found as reference but none of them are for my exact board (STM32 H735).

Does anyone have an example I can run?

[AndyJT2]

Hi,

Is HSE essential for FDCAN ?
I'm looking at STM32H503EBY6TR for a simple CAN project, however, it does not have HSE capability, so would need to use HSI anyway.
What kind of data rates or temperatures do you start to get problems with FDCAN on HSI ?

Thanks

[SomeGoose]

Hi@mhuar.1

Looking onto Your last message I would say that CAN was initialized as Classic (CAN2.0B), but TxHeader built up as FDCAN. Change this

TxHeader.FDFormat = FDCAN_FD_CAN;

to this

TxHeader.FDFormat = FDCAN_CLASSIC_CAN;

and You don't need BitRateSwitch enabled.

> I have tried loopback mode, when I do so, it runs continuously which means the FIFO is working.

I guess MCU just continuously failing to add message to the queue due to the issue above :)

Cheers.

[SomeGoose]

BTW, could be a *** question, but @mhuar.1 have You connected CAN transceiver to board CAN_{RX,TX} pins?