3 Design Steps

1. Add the EEPROM emulation library. The MSPM0 software development kit (SDK) has included the EEPROM emulation library.
   Note: The EEPROM emulation library is based on the Flash API so the drivelib from SDK is also required.
   For Type B, the following files are needed:
   1. eeprom_emulation_type_b.c
   2. eeprom_emulation_type_b.h
   Figure 3-1 EEPROM Emulation Files
2. Add the include path in the code for eeprom_emulation_type_b.h.

   Users can modify the start address, the number of groups (at least 2) and the number of sectors in one group (at least 1) in eeprom_emulation_type_b.h. The default Flash address used for EEPROM emulation is 0x00001400, and 6 sectors (3 groups, 2 sectors in every group) are used by default, so 0x00001400-0x00002bff is occupied.

   1. #define EEPROM_EMULATION_ADDRESS (0x00001400)
   2. #define EEPROM_EMULATION_GROUP_ACCOUNT (3)
   3. #define EEPROM_EMULATION_SECTOR_INGROUP_ACCOUNT (2)
3. Add the initialize function at the beginning of main(), typically after SYSCFG_DL_init(). This allows the relevant Flash areas to be formatted correctly and global variables to be allocated correctly to trace the active group and latest data item.
   • EEPROMEmulationState = EEPROM_TypeB_init();
   Figure 3-2 EEPROM Emulation Initialization
4. Use EEPROM_TypeB_write to write 32-bit data with a 16-bit identifier.
   • EEPROMEmulationState = EEPROM_TypeB_write(var_id, var_data);
   Figure 3-3 EEPROM Emulation Write
5. Use EEPROM_TypeB_readDataItem to read the data according to the input identifier.
   • var_data_read = EEPROM_TypeB_readDataItem(var_id);
   Figure 3-4 EEPROM Emulation Read
6. Add the erase function according to the gEEPROMTypeBEraseFlag. Flash needs to be erased before writing data again and the smallest unit of erasure is sector. For EEPROM emulation Type B, after one group is full, gEEPROMTypeBEraseFlag is set. Users can call EEPROM_TypeB_eraseGroup() according to the flag. For example add the following code after EEPROM_TypeB_write() from step 4. Users can also choose an appropriate timepoint to erase the full group, as needed.
   • EEPROM_TypeB_eraseGroup();
   Figure 3-5 EEPROM Emulation Erase

After steps 1 through 6, the EEPROM emulation Type B is implemented in the application. See Section 5 for the flow.