when I enable the
Auxiliary Clock 0 Select Control Register(MC_CGM_AC0_SC) the microcontroller entered reset escalation
Hello,
It looks like your clock configuration is not correct and once you enable divider it crash.
But you can check it from RGM [FES/DES] register what is the reset source.
Since you did not share which device you are running, have a look at our reference example codes. Run then and see if they are running fine.
Then you can compare them to your code.
https://community.nxp.com/t5/MPC5xxx-Knowledge-Base/MPC5-software-example-list/ta-p/1102445
Best regards,
Peter