FDCAN config issues with STM32H747I-EVAL board

[Pampah]

Hello dear community,

This is my first post here and I am coming to you for help.

In the context of a project with a STM32H747I-EVAL board (this board was lent to me and I notice that it doesn't seem to be sold anymore), I need to send/receive CAN messages with another device. I want to use FDCAN1 and FDCAN2.

I have created a project with the STM32CubeIDE with the corresponding board. When I go to the "Pinout & Configuration" view, I want to activate FDCAN1 and FDCAN2 but this is where I encounter problems. As the attached screenshots show, I encounter conflicts with other elements when trying to activate FDCAN1 and FDCAN2. These conflicts are present whatever the runtime context (M7 or M4).

I admit I am a bit lost and do not know how to continue. Why are these conflicts present? How can I solve them and use FDCAN1 and FDCAN2 ?

Waiting for your answer, I thank you for all the help you can give me.

Thank you

[SofLit · Accepted solution]

Dear @Pampah​ 

1- There are some conflicts with other functions on the board (USBOTG, FMC etc) as shown in the massages. To solve the issue, go to Pinout View and search for PA11 and PA12 as shown in the following screenshot and change the alternate function from USB or FMC etc to FDCAN1_Rx/Tx according to the GPIO you are using (PA11 or PA12).

 

FDCAN1 will be available after selecting Tx and Rx.

2- You cannot use FDCAN2 as is, as there is no transceiver available on the board. So you have to add an external transceiver for this. If it's the case make sure you disconnect other signals from the board and refer to UM2525 for this. Finally, you can follow the same steps for CubeMx described above for FDCAN1.

Hope this help you.

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