Hi Robert.

Contrary to the Arduino, the ESP32 doesn’t have an EEPROM.update() function.

However, the good news is that the EEPROM.write() on the ESP32 has the same properties of update. It only writes to EEPROM if we want to write something different.

Regards,
Sara

Hi,

Where can we get all of the EEPROM  commands and functions?

JPD

https://github.com/espressif/arduino-esp32/blob/master/libraries/EEPROM/src/EEPROM.h

Hi,

I have download the EEPROM library you referred. I have a strange output here:

name: k@?⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮”(T⸮

and  what is the use of the delay?

Regards.

JPD

/*
ESP32 eeprom_class example with EEPROM library
This simple example demonstrates using EEPROM library to store different data in
ESP32 Flash memory in a multiple user-defined EEPROM class objects.

Created for arduino-esp32 on 25 Dec, 2017
by Elochukwu Ifediora (fedy0)
converted to nvs by lbernstone - 06/22/2019
*/
#include "EEPROM.h"
// Instantiate eeprom objects with parameter/argument names and sizes
EEPROMClass NAMES("eeprom0", 0x500);
EEPROMClass HEIGHT("eeprom1", 0x200);
EEPROMClass AGE("eeprom2", 0x100);
void setup() {
Serial.begin(115200);
Serial.println("Testing EEPROMClass\n");
if (!NAMES.begin(NAMES.length())) {
Serial.println("Failed to initialise NAMES");
Serial.println("Restarting...");
delay(1000);
ESP.restart();
}
if (!HEIGHT.begin(HEIGHT.length())) {
Serial.println("Failed to initialise HEIGHT");
Serial.println("Restarting...");
delay(1000);
ESP.restart();
}
if (!AGE.begin(AGE.length())) {
Serial.println("Failed to initialise AGE");
Serial.println("Restarting...");
delay(1000);
ESP.restart();
}
const char* name = "Teo Swee Ann";
char rname[32];
double height = 5.8;
uint32_t age = 47;
// Write: Variables ---> EEPROM stores
NAMES.put(0, name);
HEIGHT.put(0, height);
AGE.put(0, age);
Serial.print("name: "); Serial.println(name);
Serial.print("height: "); Serial.println(height);
Serial.print("age: "); Serial.println(age);
Serial.println("------------------------------------\n");
// Clear variables
name = '\0';
height = 0;
age = 0;
Serial.print("name: "); Serial.println(name);
Serial.print("height: "); Serial.println(height);
Serial.print("age: "); Serial.println(age);
Serial.println("------------------------------------\n");
// Read: Variables <--- EEPROM stores
NAMES.get(0, rname);
HEIGHT.get(0, height);
AGE.get(0, age);
Serial.print("name: "); Serial.println(rname);
Serial.print("height: "); Serial.println(height);
Serial.print("age: "); Serial.println(age);

Serial.println("Done!");
}
void loop() {
delay(0xFFFFFFFF);
}

Start your code here

Testing EEPROMClass
name: Teo Swee Ann
height: 5.80
age: 47
————————————
name:
height: 0.00
age: 0
————————————
name: k@?⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮⸮”(T⸮
height: 5.80
age: 47
Done!

That’s because they are not reading the correct thing on EEPROM.
They are reading rname, when they should read name:
replace this

NAMES.get(0, rname);

with this

NAMES.get(0, name);

Then, replace this:

Serial.print(“name: “); Serial.println(rname);

With this:

Serial.print(“name: “); Serial.println(name);

This should solve the issue.
 

Thank , it does work
 
But if  after printing done I code 

Start your code here
for (int i = 0; i < EEPROM_SIZE; i++)
  {
    Serial.print(byte(EEPROM.read(i)));
    Serial.print(" ");
  }


I get only 0 (zeros).....?

That’s probably because those variables are not being saved on these addresses.

The EEPROM of ESP32  wroom  has more than 512 bytes of flash memory?

Hi,

Looking at the EEPROM library embedded in the Arduino core for the ESP32, I just noticed that this library is deprecated:

EEPROM is deprecated. For new applications on ESP32, use Preferences. EEPROM is provided for backwards compatibility with existing Arduino applications. EEPROM is implemented using a single blob within NVS, so it is a container within a container. As such, it is not going to be a high performance storage method. Preferences will directly use nvs, and store each entry as a single object therein.

It is better to use the Preferences library.
Here’s a basic example of use:

StartCounter.ino

Thanks again.

Hi.
 
EEPROM.begin(EEPROM_SIZE); //to make it work

for (int i = 0; i < EEPROM_SIZE; i++)
  {
    Serial.print(byte(EEPROM.read(i)));
    Serial.print(" ");
  }