/** * @brief Disables the write protection of user desired pages * @param None * @retval 0: Write Protection successfully disabled * 1: Error: Flash write unprotection failed * 2: Flash memory is not write protected */ uint32_t FLASH_If_DisableWriteProtection(void) { uint32_t UserMemoryMask = 0, WRPR = 0; FLASH_Status status = FLASH_BUSY; /* Clear all FLASH flags */ FLASH_ClearFlag(FLASH_FLAG_EOP | FLASH_FLAG_WRPERR | FLASH_FLAG_PGERR | FLASH_FLAG_BSY); /* Get Write protection */ WRPR = FLASH_OB_GetWRP(); /* Test if user memory is write protected */ if (FLASH_If_GetWriteProtectionStatus() != 0x00) { /* Enable the FLASH option byte access */ FLASH_OB_Unlock(); /* Erase option bytes */ status = FLASH_OB_Erase(); /* Compute the User_Mask */ UserMemoryMask = FLASH_PROTECTED_PAGES | WRPR; if (UserMemoryMask != 0xFFFFFFFF) { /* Disable Write protection */ status = FLASH_OB_EnableWRP((uint32_t)~UserMemoryMask); } if (status == FLASH_COMPLETE) { /* Write Protection successfully disabled */ return (0); } else { /* Error: Flash write unprotection failed */ return (1); } } else { /* Flash memory is not write protected */ return(2); } }
// flash save to option bytes , 2*8 bit int flash2_fmc_write( int data1 , int data2) { FLASH_Unlock(); FLASH_OB_Unlock(); FLASH_OB_Erase(); FLASH_OB_ProgramData( 0x1FFFF804, data1 ); FLASH_OB_ProgramData( 0x1FFFF806, data2 ); FLASH_Lock(); FLASH_OB_Lock(); return 0; }
/** * @brief Main program. * @param None * @retval None */ int main(void) { /*!< At this stage the microcontroller clock setting is already configured, this is done through SystemInit() function which is called from startup file (startup_stm32f0xx.s) before to branch to application main. To reconfigure the default setting of SystemInit() function, refer to system_stm32f0xx.c file */ /* Unlock the Flash Program Erase controller */ FLASH_Unlock(); FLASH_OB_Unlock(); FLASH_ClearFlag(FLASH_FLAG_EOP | FLASH_FLAG_PGERR | FLASH_FLAG_WRPERR); /* Get pages write protection status */ WRPR_Value = FLASH_OB_GetWRP(); #ifdef WRITE_PROTECTION_DISABLE /* Get pages already write protected */ ProtectedPages = ~(WRPR_Value | FLASH_PAGES_TO_BE_PROTECTED); /* Check if desired pages are already write protected */ if((WRPR_Value | (~FLASH_PAGES_TO_BE_PROTECTED)) != 0xFFFFFFFF ) { /* Erase all the option Bytes */ FLASHStatus = FLASH_OB_Erase(); /* Check if there is write protected pages */ if(ProtectedPages != 0x0) { /* Restore write protected pages */ FLASHStatus = FLASH_OB_EnableWRP(ProtectedPages); } /* Generate System Reset to load the new option byte values */ FLASH_OB_Launch(); } #elif defined WRITE_PROTECTION_ENABLE /* Get current write protected pages and the new pages to be protected */ ProtectedPages = (~WRPR_Value) | FLASH_PAGES_TO_BE_PROTECTED; /* Check if desired pages are not yet write protected */ if(((~WRPR_Value) & FLASH_PAGES_TO_BE_PROTECTED )!= FLASH_PAGES_TO_BE_PROTECTED) { /* Erase all the option Bytes because if a program operation is performed on a protected page, the Flash memory returns a protection error */ FLASHStatus = FLASH_OB_Erase(); /* Enable the pages write protection */ FLASHStatus = FLASH_OB_EnableWRP(ProtectedPages); /* Generate System Reset to load the new option byte values */ FLASH_OB_Launch(); } #endif /* WRITE_PROTECTION_DISABLE */ #ifdef FLASH_PAGE_PROGRAM /* Get the number of pages to be erased */ NbrOfPage = (BANK1_WRITE_END_ADDR - BANK1_WRITE_START_ADDR) / FLASH_PAGE_SIZE; /* The selected pages are not write protected */ if ( (WRPR_Value & FLASH_PAGES_TO_BE_PROTECTED) != 0x00) { /* Clear pending flags */ FLASH_ClearFlag(FLASH_FLAG_EOP|FLASH_FLAG_PGERR |FLASH_FLAG_WRPERR); /* erase the FLASH pages */ for(EraseCounter = 0; (EraseCounter < NbrOfPage) && (FLASHStatus == FLASH_COMPLETE); EraseCounter++) { FLASHStatus = FLASH_ErasePage(BANK1_WRITE_START_ADDR + (FLASH_PAGE_SIZE * EraseCounter)); } /* FLASH Half Word program of data 0x1753 at addresses defined by BANK1_WRITE_START_ADDR and BANK1_WRITE_END_ADDR */ Address = BANK1_WRITE_START_ADDR; while((Address < BANK1_WRITE_END_ADDR) && (FLASHStatus == FLASH_COMPLETE)) { FLASHStatus = FLASH_ProgramHalfWord(Address, Data); Address = Address + 2; } /* Check the correctness of written data */ Address = BANK1_WRITE_START_ADDR; while((Address < BANK1_WRITE_END_ADDR) && (MemoryProgramStatus != FAILED)) { if((*(__IO uint16_t*) Address) != Data) { MemoryProgramStatus = FAILED; } Address += 2; } } else { /* Error to program the flash : The desired pages are write protected */ MemoryProgramStatus = FAILED; } #endif /* FLASH_PAGE_PROGRAM */ while (1) { } }