Interesting!is it possible to check if BusFault exception is precise?>> BusFault Status Register is at 0xE000ED29From stack frame you can try to identify last PC position before the exception,>> ARM keil AN209 (Link) that might help.

@IIvan.22 "The issue (MCU freeze)" : did you confirm it is a HW freeze? from my side I think it can also result from firmware issues (CPU no more responding to other ITs when in a critical section or with a high priority IT in active state). Is Hardf...

are you managing uart communication errors within your framework?

Hi,in case 2 : "when check 2 cpu can access this SDRAM, the CM4 init FMC"Can CPU1 access the SDRAM? (just to confirm that it was correctly initialized)Br,Abdelhamid.

Hi,What kind of issue do you observed? What is the power state of D1 domain / CM7 when you try to access the SDRAM? Best regards,Abdelhamid.