2024-03-26 08:21 AM
Hello,
I am developing a CAN bus application.
I am new to the FDCAN peripheral and I haven't understood the difference between nominal bit time parameters and data bit time parameters.
Which of these two groups of parameters should I configure to obtain the desired baud-rate and sample point?
Regards,
Carlo
Solved! Go to Solution.
2024-03-26 08:37 AM
It depends on what mode you configured for your FDCAN peripheral.
Did you configure it in Classical mode? i.e. CAN2.0 of CANFD?
For Classical CAN, only Nominal bit time is taken the data bit time is discarded.
For CANFD configuration, you can have tow bitrates on a CAN frame: bitrate for the arbitration phase and another bitrate for the data phase.
refer to this link.
2024-03-26 08:37 AM
It depends on what mode you configured for your FDCAN peripheral.
Did you configure it in Classical mode? i.e. CAN2.0 of CANFD?
For Classical CAN, only Nominal bit time is taken the data bit time is discarded.
For CANFD configuration, you can have tow bitrates on a CAN frame: bitrate for the arbitration phase and another bitrate for the data phase.
refer to this link.
2024-03-26 08:49 AM
Thank you very much.
Yes, have configured the peripheral in classical mode.
So I just have to configure the nominal bit time parameters, while leaving the data bit time parameters at their default values. Isn't it?
I have always worked with CAN 2.0A, and I don't know the FDCAN extended features.
Regards,
Carlo
2024-03-26 08:54 AM
Yes, have configured the peripheral in classical mode.
So I just have to configure the nominal bit time parameters, while leaving the data bit time parameters at their default values. Isn't it?
Yes it is. keep them at default values. They are discarded by the CAN cell.
I have always worked with CAN 2.0A, and I don't know the FDCAN extended features.
It's time to start ;)
2024-03-26 09:04 AM
It's time to start ;)
Yes you are right! :grinning_face_with_sweat: