2025-09-21 11:44 AM - last edited on 2025-09-25 3:10 AM by mƎALLEm
Hi, I'm trying to configure an STM32H753 FDCAN peripheral to be compatible with both CAN-FD & CAN 2.0 frames, in both the Tx & Rx directions.
How should I configure the FD-CAN peripheral to achieve this? I've been through he RM0433 document as best I can and am struggling to find this information.
2025-09-22 11:54 AM
Are you trying to send messages to FDCAN and CAN 2.0B nodes on the same bus?
2025-09-23 2:01 AM - edited 2025-09-26 6:43 AM
Hello,
1- If you configure the peripheral in FDCAN frame format:
hfdcan1.Init.FrameFormat = FDCAN_FRAME_FD_BRS
And you can send Classic CAN frames by setting the Tx header:
TxHeader.FDFormat = FDCAN_CLASSIC_CAN;
2- But if you intend to send FDCAN frames to CAN2.0 CAN nodes, this is not possible.
From this paper: Hybridization of CAN and CAN FD networks
"While CAN FD controllers can interpret and transmit both CAN FD and Classical CAN messages, Classical CAN controllers will report CAN FD messages as an error. This mandates a strict separation of CAN FD and Classical CAN networks"