what is the difference between loopback mode and normal mode in CAN of SPC58NN84x (Bernina)

[ZMoha.1]

I am a thesis student and part of my thesis is to test the CAN of SPC58NN84x MCU in two modes, the normal mode, and the loopback mode.

The loopback mode is ok as the CAN receives the same message that it transmits properly, however, this is not the case in the normal mode as the transmission is always in "pending" and not successfully placed on the bus

The CAN controller is connected to a TJA1041 high speed can transceiver.

Can anybody tell me what is the difference between the two modes or a hint how could this be fixed and make the can works in the loopback mode properly?

[Arman Ilmak]

Loop back mode in st mcus is a test mode that simply connects can tx rx together internally in the mcu and without any CAN PHY you can simply test CAN protocol.

I think there is a problem with your can hardware that does not work in normal mode.

[ZMoha.1]

I tried to change the hardware but the problem is still the same, also there is another question from another guy that has the same problem in another board, he is using a demo board STM3210C-SK.

in a nutshell, if the problem is not hardware what could it be else?