Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32f7/STM32F730/FLASH/ACR#0x0
Flash access control register
Latency
Prefetch enable
ART Accelerator Enable
ART Accelerator reset
https://github.com/modm-io/cmsis-svd-stm32