Which faster CAN 2.0 vs FDCAN Classic

[MAmem.1]

I have two boards, one with STM32F303 with CAN 2.0 and a new board (same electronic, only MCU is different) with STM32G474. Software is identical too, except for the CAN/FDCAN. So I had to migrate the software from CAN 2.0 to FDCAN Classic in order to communicate with the other system boards.

In the treatment of the received frames, I noticed that the CAN 2.0 is faster in managing the communication than the FDCAN Classic.

Can anyone confirm that ? and if so why does it take so long to the FDCAN classic ?

As I send frames to both board, the STM32F303 program timing isn't affected, for the STM32G474 I measured a delay of some ms.

Clocks are as follow:

STM32F303 : CPU: 72 Mhz CAN baudrate: 500Kb/s

STM32G474 : CPU: 170 Mhz FDCAN classic baudrate: 500kb/s

[mƎALLEm]

Hello,

Nothing to do with the CAN protocol itself but more to your implementation in the software: need to check interrupt priorities, check if there is something disrupting the CAN reception routine by other loops/interrupts. In that case you need to use the interrupts.