@syedhashmiraza wrote:this is my code but in this code string is not storing in eeprom
So you got it to build? Well done!
How do you determine that the string is not being stored?
Is it storing anything at all ?
Did you run the demo? Did that work?
Did you study the Application Note, which describes what this code does, and how to use it?
As that description says, the EE_WriteVariable() function updates a Virtual Variable in the emulated EEPROM.
See also the documentation in the source code itself:
/**
* @brief Writes/updates variable data in EEPROM.
* @param VirtAddress: Variable virtual address
* @param Data: 16 bit data to be written
* @retval Success or error status:
* - FLASH_COMPLETE: on success
* - PAGE_FULL: if valid page is full
* - NO_VALID_PAGE: if no valid page was found
* - Flash error code: on write Flash error
*/
So that's writing 16-bit data - or two characters at once.
You will need something like:
char writeString[] = "Hello";
int string_idx = 0; // Index to characters in the string
int eeprom_idx; // Index to Virtual Variables in the emulated EEPROM
for( eeprom_idx = 0; i < strlen(writeString)/2; eeprom_idx++ )
{
if( EE_WriteVariable( VirtAddVarTab[0] + eeprom_idx, (uint16_t*)&writeString[string_idx ]) != HAL_OK)
{
Error_Handler();
}
string_idx += 2;
}
In general, you will have to also cope with
- Odd number of characters in the string
- Having enough Virtual Variables for the length of the string.
In both cases, you are lucky so far that this happens to be OK.
As I said initially:
"It may not exactly suit your requirements, but it does show how to use the STM32F4 Flash for data storage."
It certainly isn't great for saving strings ...
