SYSCFG Cortex-M55 control register
| FPU_IT_EN | Enable FPU exception  |  
| LOCKSVTAIRCR | Prevent changes to:  |  
| LOCKNSVTOR | Prevent changes to the non-secure vector table base address.  |  
| LOCKSMPU | Prevent changes to programmed secure MPU memory regions.  |  
| LOCKNSMPU | Prevent changes to non-secure MPU memory regions already programmed.  |  
| LOCKSAU | Prevent changes to secure SAU memory regions already programmed.  |  
| LOCKDCAIC | Disable access to the instruction cache direct cache access registers DCAICLR and DCAICRR.  |