NXP Semiconductors freescale K51 Series Reference Manual

FlexRAM Data flash 1DEPART /2EEPROMbackup BFlexNVM Block 1Subsystem BEEESIZEUnavailableEEPROM partition ADEPART /2 FlexNVM Block 0Subsystem ASize of EEPROM partition A = EEESIZE x EEESPLITData flash 0 and 1 interleavedData flash 0EEPROM partition BEEPROMbackup AEEESPLIT = 1/8, 1/4, or 1/2Figure 28-32. FlexRAM to FlexNVM Memory Mapping with 2 Sub-systems28.4.3.3 EEPROM Implementation OverviewOut of reset with the FSTAT[CCIF] bit clear, the partition settings (EEESIZE, DEPART,EEESPLIT) are read from the data flash IFR and the EEPROM file system is initializedaccordingly. The EEPROM file system locates all valid EEPROM data records inEEPROM backup and copies the newest data to FlexRAM. The FSTAT[CCIF] andFCNFG[EEERDY] bits are set after data from all valid EEPROM data records is copiedto the FlexRAM. After the CCIF bit is set, the FlexRAM is available for read or writeaccess.When configured for EEPROM use, writes to an unprotected location in FlexRAMinvokes the EEPROM file system to program a new EEPROM data record in theEEPROM backup memory in a round-robin fashion. As needed, the EEPROM filesystem identifies the EEPROM backup sector that is being erased for future use andpartially erases that EEPROM backup sector. After a write to the FlexRAM, theFlexRAM is not accessible until the FSTAT[CCIF] bit is set. The FCNFG[EEERDY] bitwill also be set. If enabled, the interrupt associated with the FSTAT[CCIF] bit can beused to determine when the FlexRAM is available for read or write access.Chapter 28 Flash Memory Module (FTFL)K51 Sub-Family Reference Manual, Rev. 6, Nov 2011Freescale Semiconductor, Inc. 635