No CAN Communication on STM32H723ZG-E01 (A230801274)

[mani9989]

Dear STMicroelectronics Support,

I am working with the STM32H723ZG-E01 board (Serial: A230801274) and encountering an issue where CAN communication is not functioning as expected.

Based on the documentation, I have configured the FDCAN1 interface to use PD0 (FDCAN1_RX) and PD1 (FDCAN1_TX). The FDCAN peripheral clock is set to 20 MHz. The external transceiver is correctly connected and powered, and the rest of the board appears to function normally.

Despite this setup, no CAN or CAN FD communication is taking place. I would appreciate your help with the following:

1. Could you please confirm whether PD0 and PD1 are valid and officially supported pins for FDCAN1 on this specific board?

2. Are there any known limitations, errata, or special configuration requirements for using these pins?

3. Could you kindly share a sample .ioc configuration file and example code (bare metal or HAL-based) for basic CAN or CAN FD communication on the STM32H723ZG-E01 board?

This would greatly help us verify our setup and ensure we're not missing any critical configuration steps.

Thank you for your assistance.

Best regards,
Kasani Manikanta 

[Tesla DeLorean]

Sorry, which board? The NUCLEO-H723ZI ?

Download a schematic from the "CAD Resources" tab on the product page, check the pin wiring for the pins of interest to determine if there are any immediate and obvious conflicts.

For canned example, perhaps look at some of the STM32H7 EVAL/DISCO series boards, which come prepopulated with CAN hardware. Should be some in the CubeH7 example trees.

Direct support should be sought via your local sales rep or FAE (support engineer)

Also consider using the Online Support system.  https://ols.st.com/s/

[mani9989]

The board is NUCLEO-H723ZG. 

I checked their no example for CAN of the NUCLEO-H7xx boards.

[mƎALLEm]

Hello @mani9989 and welcome to the community,

Please reveiw that article: STM32 FDCAN running at 8 Mb/s on NUCLEO boards

NUCLEO-H723ZG is not available as example on the article (Github hotspot link) only NUCLEO-H753ZI is supported. But you can easily port the example from STM32H753 to STM32H723. The example is already using PD0 and PD1 GPIOs + STLINKV3-MCO output as clock source for the system clock. Refer also to this article: How to use STLINK-V3 MCO output on Nucleo boards as a precise clock source for STM32

Hope that helps.

[Tesla DeLorean]

>>I checked their no example for CAN of the NUCLEO-H7xx boards.

Correct, because ST doesn't have any CAN support hardware on those boards, I said to look at DISCO/DK, or EVAL boards which DO.

https://github.com/STMicroelectronics/STM32CubeH7/tree/master/Projects/STM32H743I-EVAL/Examples/FDCAN

https://github.com/STMicroelectronics/STM32CubeH7/tree/master/Projects/STM32H7B3I-EVAL/Examples/FDCAN/FDCAN_Loopback

And perhaps more BROADLY at other STM32 families with FDCAN and BOARDs supporting it. Which should share a common HAL and IP implementation. Most of this stuff is highly portable, but might take a little work or thought on the part of the engineer.

ST's examples are for boards they sell, the code generator should be able to manifest examples for other board and chip combinations, but won't have been validated to the same degree.

[Tesla DeLorean]

https://community.st.com/t5/stm32-mcus-products/nucleo-h743zi2-fdcan-late-trigger-of-rx-interrupts/td-p/743412

@mƎALLEm 

[mani9989]

@mƎALLEm  & @Tesla DeLorean , Thanks for quick response and update. 

As mentioned I took over the code of STM32H753 and executed it but still I see no CAN frames. 

I have attached my connections.

[Tesla DeLorean]

Can you circuit diagram your transceiver and connectivity for what you've built?

Interest in specific part#, and pins beyond just PD0/PD1

The PD0/PD1 are vertically flipped on CN11 vs CN9 connectors

On CN9 PD0/CANRX Upper (North), PD1/CANTX Lower (South)

The schematic doesn't suggest the pins are encumbered by any other connectivity or solder bridges.

Perhaps focus on the pin configuration code, that it's called and the correct AF setting is in use.

[mƎALLEm]

Did you port the example from STM32H753 to STM32H723 or uplaod the example without any modification?

Also, what is the hardware you are using? here I mean the complete CAN bus. Post a sketch of your nodes with the CAN bus.

Moreover, please read the two articles I provided in my previous comment. We are providing such articles to help users to solve their issues.