Flash option control register
| OPTLOCK | Option lock |
| OPTSTRT | Option start |
| BOR_LEV | BOR reset Level |
| WWDG_SW | User option bytes |
| IWDG_SW | WDG_SW User option bytes |
| nRST_STOP | nRST_STOP User option bytes |
| nRST_STDBY | nRST_STDBY User option bytes |
| RDP | Read protect |
| nWRP | Not write protect |
| IWDG_STDBY | Independent watchdog counter freeze in standby mode |
| IWDG_STOP | Independent watchdog counter freeze in Stop mode |