fsl_mcan.c not able to clear bits in XIDFC and GFC registers?

[Ken_V]

I am using the LPC54608 microcontroller and the SDK for Keil tools IDE.

In my application I need to change the acceptance registers from what was originally set up.

The "MCAN_SetFilterConfig" function to set the registers, but it only ORs the value, so bits already set can't be cleared...

base->GFC |= CAN_GFC_RRFE(config->remFrame) | CAN_GFC_ANFE(config->nmFrame);
base->XIDFC |= CAN_XIDFC_FLESA(config->address >> CAN_XIDFC_FLESA_SHIFT) | CAN_XIDFC_LSE(config->listSize);

Is this a bug, or is there something I'm missing?

[Alice_Yang]

Hello Ken,

If you want to change the acceptance registers, yes, you really need your second code (FIXED CODE), because your original code keep original setting.

BR

Alice

BR

Alice

[Alice_Yang]

Hello Ken,

About set CAN ID filter, you can have a look at this thread:

https://community.nxp.com/t5/LPC-Microcontrollers/CAN-with-Extended-ID-filtering-how-to-set-multiple...

BR

Alice

[Ken_V]

I have no problem setting up multiple filter configurations...

I need to change the configuration later at some point in time and the current driver code does not allow doing that unless I preclear the registers or fix the driver code as shown below to set it equal to the config settings instead of ORing them...

ORIGINAL CODE

// base->GFC |= CAN_GFC_RRFE(config->remFrame) | CAN_GFC_ANFE(config->nmFrame);
// base->XIDFC |= CAN_XIDFC_FLESA(config->address >> CAN_XIDFC_FLESA_SHIFT) | CAN_XIDFC_LSE(config->listSize);

FIXED CODE
base->GFC = CAN_GFC_RRFE(config->remFrame) | CAN_GFC_ANFE(config->nmFrame);
base->XIDFC = CAN_XIDFC_FLESA(config->address >> CAN_XIDFC_FLESA_SHIFT) | CAN_XIDFC_LSE(config->listSize);

Is there something I'm missing that makes this work correctly with supplied drivers?