Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32H7x5_CM7/SYSCFG/UR13#0x0
SYSCFG user register 13
Secured DTCM RAM Size
D1 Standby reset
https://github.com/cmsis-svd/cmsis-svd-data