The EEPROM_Config_Check() function provides general error-checking and configures Write/Erase protection masks required by the Flash API. This function must be called before programming or reading from the emulated EEPROM Unit(s).

First, the function verifies that the Flash Bank selected for EEPROM Emulation are valid. A valid Flash Bank selection must not select Bank 0 for emulation and must be supported by a specific device variant. For example, only specific F28p65x variants have Flash Banks 2-4. To verify this information, see the device-specific data-sheet.

if (FLASH_BANK_SELECT == FlashBank0StartAddress)
{
    return 0xFFFF;
}

if (FLASH_BANK_SELECT == FlashBank2StartAddress)
{
#if !defined(F28P65xDKx) && !defined(F28P65xSKx) && !defined(F28P65xSHx)   
        return 0xFFFF;
#endif
} else if (FLASH_BANK_SELECT == FlashBank3StartAddress) // If using Bank 3
{
#if !defined(F28P65xDKx) && !defined(F28P65xSKx)   
        return 0xFFFF;
#endif
} else if (FLASH_BANK_SELECT == FlashBank4StartAddress) 
{
#if !defined(F28P65xDKx) && !defined(F28P65xSKx) && !defined(F28P65xSHx)   
        return 0xFFFF;
#endif
}

Second, the validity of Flash Sectors selected for emulation is examined. This function checks for:

• More Flash Sectors selected for emulation than available within the Flash Bank

NUM_EEPROM_SECTORS = FIRST_AND_LAST_SECTOR[1] - FIRST_AND_LAST_SECTOR[0] + 1;
if (NUM_EEPROM_SECTORS > NUM_FLASH_SECTORS || NUM_EEPROM_SECTORS == 0)
{
    return 0xEEEE;
}

• Invalid combinations for First and Last Sectors selected for emulation

if (NUM_EEPROM_SECTORS > 1)
{
    if (FIRST_AND_LAST_SECTOR[1] <= FIRST_AND_LAST_SECTOR[0])
    {
        return 0xEEEE;
     }
     // Check if SECTOR_NUMBERS contains invalid sector
    if (FIRST_AND_LAST_SECTOR[0] > NUM_FLASH_SECTORS - 1)
    {
        return 0xEEEE;
    }
    if (FIRST_AND_LAST_SECTOR[1] > NUM_FLASH_SECTORS - 1 || FIRST_AND_LAST_SECTOR[1] < 1)
    {
        return 0xEEEE;
    }
} else // If only one sector, validate the sector is input properly
{

// Verify that the only sector is valid
if (FIRST_AND_LAST_SECTOR[0] > NUM_FLASH_SECTORS - 1) {
    return 0xEEEE;
}

If using Page Mode, the following is also be checked for

• Check if total size of EEPROM Banks + Pages fit in the Flash Sectors selected

// Calculate size of each EEPROM Bank (16 bit words)
Bank_Size = 8 + ((EEPROM_PAGE_DATA_SIZE + 8) * NUM_EEPROM_PAGES);

// Calculate amount of available space (16 bit words)
uint32 Available_Words = NUM_EEPROM_SECTORS * FLASH_SECTOR_SIZE;

// Check if size of EEPROM Banks and Pages fit in EEPROM sectors
if (Bank_Size * NUM_EEPROM_BANKS > Available_Words)
{
    return 0xCCCC;
}

The code also warns the user with the appropriate code if one of the following conditions is detected:

• Space for one or more EEPROM Banks is left in Flash after configuring EEPROM Bank and Page size

// Notify for extra space (more than one bank leftover)
if (Available_Words - (Bank_Size * NUM_EEPROM_BANKS ) >= Bank_Size)
{
    Warning_Flags += 1;
}

• If each page consists of less than 5 16-bit words (this wastes space as the 64-Bit Mode can be used without the need for Status Codes)

if (EEPROM_PAGE_DATA_SIZE < 5)
{
    Warning_Flags += 2;
}

• If using sectors in the 32-127 range (for F28P65x devices) and not using all eight sectors allocated to a single bit in the Write Protection Mask, a warning is issued. Any unused sectors within the eight designed by a single bit cannot be properly be protected from erase. For more details on the Write Protection Masks, see the TMS320F28P65x Flash API Version 3.02.00.00 Reference Guide.

if (FIRST_AND_LAST_SECTOR[1] > 31) {

    if (FIRST_AND_LAST_SECTOR[0] > 31)
    {

        if (NUM_EEPROM_SECTORS < 8) {
            Warning_Flags += 4;
        } else {

            if ((FIRST_AND_LAST_SECTOR[0] % 8) != 0 || ((FIRST_AND_LAST_SECTOR[1] + 1) % 8 != 0))
            {
                Warning_Flags += 4;
            }
        }
    } else
    { 


        if ((FIRST_AND_LAST_SECTOR[1] + 1) % 8 != 0)
        {
            Warning_Flags += 4;
        }
    }
}

Finally, Write/Erase Protection masks are configured for the Active EEPROM Unit. This function also prepares Flash for Emulation by erasing the Sectors to be used for programming.

uint64 WE_Protection_AB_Mask = Configure_Protection_Masks(FIRST_AND_LAST_SECTOR, NUM_EEPROM_SECTORS);


WE_Protection_A_Mask = 0xFFFFFFFF ^ (uint32)WE_Protection_AB_Mask;
WE_Protection_B_Mask = 0x00000FFF ^ WE_Protection_AB_Mask >> 32;


EEPROM_Erase();