Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/STMicroelectronics/STM32F7x8/FMC/SDSR#0x0
SDRAM Status register
Refresh error flag
Status Mode for Bank 1
Status Mode for Bank 2
Busy status
https://github.com/cmsis-svd/cmsis-svd-data