Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/stm32/stm32f7/STM32F730/OTG_HS_DEVICE/OTG_HS_DVBUSPULSE#0x0
OTG_HS device VBUS pulsing time register
Device VBUS pulsing time
https://github.com/modm-io/cmsis-svd-stm32