#include <EEPROM.h>

#define LED 13
#define StateAddress 0
#define btn 2

void setup() {
  // put your setup code here, to run once:
  EEPROM.write(StateAddress, 0); //Sets address to 0 to simulate a set value being carried over

  String EERead;
  pinMode(LED, OUTPUT);
  pinMode(btn, INPUT);
  EERead = EEPROM.read(StateAddress);
  digitalWrite(LED, EEPROM.read(StateAddress));
  Serial.begin(9600);
  Serial.println(EEPROM.read(StateAddress));
}

void loop() {
  //put your main code here, to run repeatedly:
  if (digitalRead(btn) == HIGH && EEPROM.read(StateAddress) == 0) {
    EEPROM.write(StateAddress, 1);
    digitalWrite(LED, HIGH);
    Serial.println(EEPROM.read(StateAddress));
    while(digitalRead(btn) == HIGH) {}
  }
  else if(digitalRead(btn) == HIGH && EEPROM.read(StateAddress) == 1) {
    EEPROM.write(StateAddress, 0);
    digitalWrite(LED, LOW);
    Serial.println(EEPROM.read(StateAddress));
    while(digitalRead(btn) == HIGH) {}
  }
}