eeprom_get.ino

/***
    eeprom_get example.

    This shows how to use the EEPROM.get() method.

    To pre-set the EEPROM data, run the example sketch eeprom_put.
    This sketch will run without it, however, the values shown
    will be shown from what ever is already on the EEPROM.

    This may cause the serial object to print out a large string
    of garbage if there is no null character inside one of the strings
    loaded.

    Modified to C for use with SDuino by Michael Mayer 2018
    Written by Christopher Andrews 2015
    Released under MIT licence.
***/

#include <EEPROM.h>

void secondTest();

void setup() {

  float f = 0.00f;   //Variable to store data read from EEPROM.
  int eeAddress = 0; //EEPROM address to start reading from

  Serial_begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only
  }
  Serial_print_s("Read float from EEPROM: ");

  //Get the float data from the EEPROM at position 'eeAddress'
  EEPROM_get(eeAddress, f);
  Serial_println_fd(f, 3);    //This may print 'ovf, nan' if the data inside the EEPROM is not a valid float.

  /***
    As get also returns a reference to 'f', you can use it inline.
    E.g: Serial.print( EEPROM.get( eeAddress, f ) );
  ***/

  /***
    Get can be used with custom structures too.
    I have separated this into an extra function.
  ***/

  secondTest(); //Run the next test.
}

struct MyObject {
  float field1;
  byte field2;
  char name[10];
};

void secondTest() {
  int eeAddress = sizeof(float); //Move address to the next byte after float 'f'.

  struct MyObject customVar; //Variable to store custom object read from EEPROM.
  EEPROM_get(eeAddress, customVar);

  Serial_println_s("Read custom object from EEPROM: ");
  Serial_println_f(customVar.field1);
  Serial_println_u(customVar.field2);
  Serial_println_s(customVar.name);
}

void loop() {
  /* Empty loop */
}