FLASH FLASH 0x0 0x400 registers ACR ACR Flash access control register 0x0 0x20 0x00000000 LATENCY Latency 0 3 read-write PRFTEN Prefetch enable 8 1 read-write ICEN Instruction cache enable 9 1 read-write DCEN Data cache enable 10 1 read-write ICRST Instruction cache reset 11 1 write-only DCRST Data cache reset 12 1 read-write KEYR KEYR Flash key register 0x4 0x20 write-only 0x00000000 KEY FPEC key 0 32 OPTKEYR OPTKEYR Flash option key register 0x8 0x20 write-only 0x00000000 OPTKEY Option byte key 0 32 SR SR Status register 0xC 0x20 0x00000000 EOP End of operation 0 1 read-write OPERR Operation error 1 1 read-write WRPERR Write protection error 4 1 read-write PGAERR Programming alignment error 5 1 read-write PGPERR Programming parallelism error 6 1 read-write PGSERR Programming sequence error 7 1 read-write BSY Busy 16 1 read-only CR CR Control register 0x10 0x20 read-write 0x80000000 PG Programming 0 1 SER Sector Erase 1 1 #if defined(STM32F427) || defined(STM32F437) || defined(STM32F429) || defined(STM32F439) MER Mass Erase of sectors 0 to 11 2 1 SNB Sector number 3 5 MER1 Mass Erase of sectors 12 to 23 15 1 #else MER Mass Erase 2 1 SNB Sector number 3 4 #endif PSIZE Program size 8 2 STRT Start 16 1 EOPIE End of operation interrupt enable 24 1 ERRIE Error interrupt enable 25 1 LOCK Lock 31 1 OPTCR OPTCR Flash option control register 0x14 0x20 read-write 0x0FFFAAED OPTLOCK Option lock 0 1 OPTSTRT Option start 1 1 BOR_LEV BOR reset Level 2 2 WDG_SW WDG_SW User option bytes 5 1 nRST_STOP nRST_STOP User option bytes 6 1 nRST_STDBY nRST_STDBY User option bytes 7 1 RDP Read protect 8 8 nWRP Not write protect 16 12 #if defined(STM32F427) || defined(STM32F437) || defined(STM32F429) || defined(STM32F439) OPTCR1 OPTCR1 Flash option control register 1 0x18 0x20 read-write 0x0FFF0000 nWRP Not write protect 16 12 #endif