A simple and reliable EEPROM emulation library written in C for STM32 (HAL-based).

This library allows you to store and retrieve non-volatile data using the STM32's internal Flash memory — ideal for devices that do not include dedicated EEPROM.

It provides a lightweight API for initialization, read, write, format, and capacity management, making it easy to integrate into any STM32 project.

It supports all STM32 series.

• 🧩 Fully blocking, synchronous operation
• 💾 Uses internal Flash for data storage
• 🧱 Configurable page/sector size and memory layout (Auto and Manual)
• 🧠 Supports data structure mapping for easy use
• ⚙️ Works with both single-bank and dual-bank Flash configurations
• 🔐 Safe write mechanism to protect existing data
• 📂 Clean, modular, and portable API

You can add the library to your STM32 project in two ways:

Add these files to your project:

• ee.h
• ee.c
• ee_config.h

Include them in your application source files and compile.

Future support will be available via the official STM32 pack repository.

Defines page/sector sizes and optional manual Flash configuration or Use Auto Selection (define EE_MANUAL_CONFIG = 0).

/* USER CODE BEGIN EE_CONFIGURATION */

#define EE_MANUAL_CONFIG                  0
#if (EE_MANUAL_CONFIG == 1)
#define EE_SELECTED_PAGE_SECTOR_NUMBER    16
#define EE_SELECTED_PAGE_SECTOR_SIZE      EE_PAGE_SECTOR_SIZE_1K
#define EE_SELECTED_BANK                  FLASH_BANK_1
#define EE_SELECTED_ADDRESS               0x08000000
#endif

/* USER CODE END EE_CONFIGURATION */

Use your data structure like this:

#include "ee.h"

typedef struct
{
 uint32_t val1;
 int16_t val2;
 int8_t val3;
 float val4;

} stotrage_t;

stotrage_t ee_data;

int main(void)
{
  // HAL / system init ...
  // ...

  ee_init(&ee_data, sizeof(stotrage_t));
  ee_read();

  ee_data.val1 = 10000;
  ee_data.val2 = -202;
  ee_data.val3 = -3;
  ee_data.val4 = 4.5f;

  ee_write();

  while (1)
  {
    // main loop...
  }
}

• Flash erase/write cycles are limited — avoid frequent writes.
• For some series should enable 'EE_MANUAL_CONFIG'.

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Licensed under the terms in the LICENSE.