Receiving duplicated FDCAN messages STM32N6

[guillerminaborrazas]

Hello,

I am working with the FDCAN peripheral on the STM32N6 Nucleo Board. While logging all received and transmitted messages, I noticed that some messages are received twice.

Is there a specific reason for this behavior? Should I introduce a delay before reading the RxFIFO again?

Thank you in advance for your support.

Best regards,

Guillermina

[mƎALLEm]

Hello,

Are you sure the message are not physically duplicated on the bus? did you check that with a CAN analyzer or an oscilloscope?

[guillerminaborrazas]

Hi @mƎALLEm ! Thank you for your quick response.

I checked and the message is sent twice indeed.

The slave is a STM32H563VIT6. In the code the message is only sent once.

I also checked the article : 

https://community.st.com/t5/stm32-mcus/faq-fixing-stm32-fdcan-communication-disruptions-apb-bus-kernel/ta-p/730298

But the quanta clock is below the APB clock in both master and slave.

Any ideas of what can be happening?

Thank you!

[guillerminaborrazas · Accepted solution]

Hello @mƎALLEm, I changed the APB clocks frequency to match the SYS clk, and the issue dissapeared.