How to adjust FlexCAN clock source for CAN requirement of S32K312?

[f-nelson]

Hi NXP:
we have tested CAN-FD function with PCAN device as loopback behavior and it can work well.
nowadays we got CAN-FD specification from customer, they need CAN clock 40Mhz for communication bewteen 500Kbps and 2Mbps.
this project is from FreeRTOS sample code and have modified FlexCAN clock source from 24Mhze(FIRC_CLK) to 30Mhz(AIPS_PLAT_CLK).
currently, I can't adjust FlexCAN clock source 40Mhz for customer.please help us, many thanks.

environment:
MCU:S32K312/100pin
S32DS Product:3.5.0.202207261815
RTD S32KXX:RTD5.0.0.202407261948
SW32K3_FreeRTOS_11.1.0_5.0.0_CD1_D2409_Example Project

sample project attachment:
FreeRTOS_S32K312_FlexCAN_clk.7z

BR
Nelson

[PetrS · Accepted solution]

Hi,

CAN PE clock can be derived from AIPS_PLAT, FIRC or FXOSC clock sources.
If customer really need to have 40MHz CAN PE clk, even if this is not necessary for used bitrate setting, then they either need to use 40MHz external crystal in their design, or need to reduce CORE_CLK to 80MHz so then AIPS_PLAT_clk will be 40MHz.

BR, Petr