EEPROM_Preferences (WIP)

Arduino Library for I2C EEPROM - 24LC256/64/32/16/08/04/02/01.

Description

This library allows to interact with external I2C EEPROM in the style of the ESP32 Preferences.h library, avoiding the user having to manage the memory addresses.

Example

#include <EEPROM_Preferences.h>

EEPROM_Preferences preferences(0x50, EEPROM_24LC256);

void setup() {
  Serial.begin(115200);

  preferences.begin();

  preferences.writeBool("bool", true);
  Serial.println(preferences.getBool("bool", false));

  preferences.writeString("welcome", "Hello word");
  Serial.println(preferences.getString("welcome", ""));
}

void loop() {
}

Connection diagram

3.3V and 5V can be used!

Interface

Constructor

EEPROM_Preferences(const uint8_t deviceAddress, const uint16_t deviceSize, TwoWire *wire = &Wire);

Initialization

• Initializes the eeprom and configures the write protection pin if necessary

void begin(int8_t writeProtectPin = -1);

Read methods

• Obtains a string through a key, if the key is not found in memory, it will return the default value indicated in the second parameter

char* getString(const char* key, const char* defaultValue);

• Obtains an int through a key, if the key is not found in memory, it will return the default value indicated in the second parameter

int getInt(const char* key, int defaultValue);

• Obtains an uint through a key, if the key is not found in memory, it will return the default value indicated in the second parameter

int getUInt(const char* key, int defaultValue);

• Obtains a float through a key, if the key is not found in memory, it will return the default value indicated in the second parameter

float getFloat(const char* key, float defaultValue);

• Obtains a bool through a key, if the key is not found in memory, it will return the default value indicated in the second parameter

bool getBool(const char* key, bool defaultValue);

Write methods

• Writes a string to memory using the specified key

StatusCode writeString(const char* key, const char* value);

• Writes an int to memory using the specified key

StatusCode writeInt(const char* key, int32_t value);

• Writes an uint to memory using the specified key

StatusCode writeUInt(const char* key, uint32_t value);

• Writes a float to memory using the specified key

StatusCode writeFloat(const char* key, float value);

• Writes a bool to memory using the specified key

StatusCode writeBool(const char* key, bool value);

Others

• Removes string record by value from memory and reallocate memory

StatusCode removeString(const char* key);

• Removes int record by value from memory and reallocate memory

StatusCode removeInt(const char* key);

• Removes uint record by value from memory and reallocate memory

StatusCode removeUInt(const char* key);

• Removes bool record by value from memory and reallocate memory

StatusCode removeBool(const char* key);

• Removes float record by value from memory and reallocate memory

StatusCode removeFloat(const char* key);

• Enable write protection mode on the memory

void enableWrite();

• Disable write protection mode on the memory

void disableWrite();

• Completely clears the memory (it takes some time to perform this operation)

bool freeEEPROM();

• Dumps register data from EEPROM, address should be multiple of 32

const char* dumpRecord(uint16_t address);

StatusCode

Code	Text
0	No errors found
1	Memory is full
2	Key not found (only on remove)
3	Key length overflow (only on write)
4	Data length overflow (only on write)
5	Memory is write protected

To-Do

• Add support to all 24LCXXX memories (only tested with 24LC256)

Credits

Inspired by RobTillaart's I2C_EEPROM library (https://github.com/RobTillaart/I2C_EEPROM) and ESP32 Preferences library