Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Keil/AT32A403Axx_v2/USBFS/INTSTS#0x0
interrupt status register
Endpoint number
In/Out transaction
Lost start of frame
start of frame
Bus reset
Bus suspend
Wakeup
Bus error
USB core fifo overrun memory
transaction completed
https://github.com/cmsis-svd/cmsis-svd-data