FlexCAN baudrate parameters

[davithakobyan]

Dear All,

Could someone from NXP clarify if for classical CAN (S32K144) one has to use the FlexCAN's CTRL1 register for setting up the baudrate parameters or one can equally use the CBT register?

The manual says that CTRL1 is left for backward compatibility meaning that for new projects one should use the CBT register and consequently to have a broader range of values for configuring the baudrate parameters? So if CBT is fine to be used in classical CAN then one is no longer abide to restrictions of CTRL1 register like the table below?

When the CAN FD is not enabled then the FLEXCAN_DRV_SetBitrate function of the SDK calls the FLEXCAN_SetTimeSegments which eventually writes to CTRL1 register.

So it is not clear if one can use the CBT register in classical CAN then why does the driver function use the CTRL1 register? And if it is not allowed to use the CBT register in classical CAN why does the manual mention that CTRL1 is left only for backward compatibility?

Thanks a lot in advance.

[PetrS · Accepted solution]

Hi,

yes, the CBT can be used for bitrate setting for classical CAN format too and you need not to follow parameters given in that table.

As you wrote, the SDK driver uses CTRL1 if CAN FD is disabled so if you want to use CBT you need to write it by own.

BR, Petr