Skip to main content
CZ_Home
Visitor II
September 21, 2025
Solved

STM32H753 CAN set up with both CAN-FD & CAN 2.0 frames

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.

This topic has been closed for replies.
mƎALLEm
mƎALLEmBest answer
ST Technical Moderator
September 23, 2025

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"

To give better visibility on the answered topics, please click "Best answer" on the reply which solved your issue or answered your question.
View in thread

2 replies

Karl Yamashita
Karl Yamashita
Principal
September 22, 2025

Are you trying to send messages to FDCAN and CAN 2.0B nodes on the same bus? 

If a reply has proven helpful, click on Accept as Solution so that it'll show at top of the post.CAN Jammer an open source CAN bus hacking toolCANableV3 Open Source
mƎALLEm
mƎALLEmBest answer
ST Technical Moderator
September 23, 2025

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"

To give better visibility on the answered topics, please click "Best answer" on the reply which solved your issue or answered your question.
Terms & ConditionsAccessibility statement