ESP32 Forum

Posted: **Sun Sep 02, 2018 9:07 pm**

Hello,

I am porting a SW from ATMega to ESP32 and have some difficulties with the EEPROM as apparently nothing is stored. I have added the initialization sequence

Code: Select all

 Serial.println("\nTesting EEPROM Library\n");
  if (!EEPROM.begin(EEPROM.length())) {
    Serial.println("Failed to initialise EEPROM");
    Serial.println("Restarting...");
    delay(1000);
    ESP.restart();
  }

But this is permanently failing. I am using an ESP32 VROOM module.
What do I miss ?

Posted: **Mon Sep 03, 2018 10:14 am**

EEPROM.length() has a default value of 0, so begin() will fail.

Two options:

Initialise an EEPROMClass and provide it with a size

Code: Select all

EEPROMClass myEeprom("eeprom",64);
if(!myEeprom.begin(myEeprom.length()))
{
    Serial.println("failed to initialise myEeprom");
}

or pass the size into EEPROM.begin()

Code: Select all

#define EEPROM_SIZE 64
if (!EEPROM.begin( EEPROM_SIZE ))
{
    Serial.println("failed to initialise EEPROM");
}

Or, even better, use the Preferences library. It's EEPROM on steroids.

Posted: **Mon Sep 03, 2018 3:51 pm**

Ok, thanks. I had found the solution briefly before you post. Now everything works as expected.

I have one additional question concerning the NVS area. How to access it ?

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