Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Nuvoton/NUC1xx_registers/USB/USB_FLDET#0x0
Device Floating Detected
1: When the controller is attached into the BUS, this bit will be set as 1 0: The controller didn’t attached into the USB host
https://github.com/cmsis-svd/cmsis-svd-data