FDCAN - 2 Nucleo G0B1RE Board - What i am doing wrong ?

SBrun.5 · ‎2021-12-15

Hello,

I am currently working with 2 Nucleo-G0B1RE board. I adapted the "FDCAN_Com_IT_2_BOARDS" from the G0C1RE-EV example.

Clocks are the same, so i think the fdcan is properly setup.

I changed the RX/TX pin from PD12/PD13 to PA11/PA12, and connected the 2 board together, without using FDCAN transceiver, just using RX/TX pin.

When using FDCAN_MODE_EXTERNAL_LOOPBACK mode, my signal looks fine, but in normal mode, i always get a bit error (first transmission).

What i am doing wrong ?

Thanks for your help

SofLit · ‎2021-12-23

Dear SBrun.5,

In CAN normal mode you need to have a complete CAN bus: your board + transceiver and at least another node (with its transceiver) connected to the bus + termination resistors (120ohm x2) to establish a minimal CAN communication.

CAN is not SPI or UART. It needs a minimal hardware configuration to establish a communication. That's why there is the loopback mode to run CAN preliminary tests or debug (like your case)..

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.

View solution in original post

SofLit · ‎2021-12-23

Dear SBrun.5,

In CAN normal mode you need to have a complete CAN bus: your board + transceiver and at least another node (with its transceiver) connected to the bus + termination resistors (120ohm x2) to establish a minimal CAN communication.

CAN is not SPI or UART. It needs a minimal hardware configuration to establish a communication. That's why there is the loopback mode to run CAN preliminary tests or debug (like your case)..

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.