#include <EEPROM.h>
float x = 0 ;

void setup() {
  Serial.begin(9600);
  x = EEPROM.read(0);
  Serial.println("Writing...");
  if(x == 255){
    x = 12.3695;
    EEPROM.put(0, x);// บันทึกค่าตัวแปร
    Serial.println("Write Value OK!");
  }
  Serial.println("Reading...");
  Serial.println(EEPROM.get(0, x),4);
}
void loop() {
}