Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Keil/AT32A403Axx_v2/USBFS/SOFRNUM#0x0
frame number register
Start of frame number
Lost start of frame number
Connect locked
DM status
DP status
https://github.com/cmsis-svd/cmsis-svd-data