#include <SPI.h>
#define READ 0x03 //read command
#define WRITE 0x02 //write command
#define WREN 0x06  // write enable

const int csPin = 10;
const int wpPin = 9; // For this sketch you could also leave the wpPin unconnected
const int writeCycle = 10;

void setup(){
  pinMode(csPin, OUTPUT);
  digitalWrite(csPin, HIGH);
  pinMode(wpPin, OUTPUT);
  digitalWrite(wpPin,HIGH);
  SPI.begin();
  Serial.begin(9600);

  eepromWriteEnable();// enable write enable latch bit
  digitalWrite(csPin, LOW);
  SPI.transfer(0x60); //chip erase command
  digitalWrite(csPin, HIGH);
  delay(8000); //max time taken for chip erase to process

  int intToWrite = 42;
  eepromWriteInt(4, intToWrite);
  intToWrite = -1111;
  eepromWriteInt(6, intToWrite);

  int intToRead = 0;
  intToRead = eepromReadInt(4);
  Serial.print("intToRead (Address = 4): ");
  Serial.println(intToRead);
  intToRead = 0;
  intToRead = eepromReadInt(6);
  Serial.print("intToRead (Address = 6): ");
  Serial.println(intToRead);
}

void loop(){}

void eepromWriteEnable(){
  digitalWrite(csPin, LOW);
  SPI.transfer(WREN); //set write enable latch
  digitalWrite(csPin, HIGH);
}

void eepromWriteInt(int addr, int value){
  eepromWriteEnable();
  delay(100);
  // If you want to change the SPI clock speed, uncomment the following line and adjust
  SPI.beginTransaction(SPISettings(4000000, MSBFIRST, SPI_MODE0));
  digitalWrite(csPin, LOW);
  SPI.transfer(WRITE);  //write command
  SPI.transfer((byte)(addr>>16)); //1st byte of 2 byte address
  SPI.transfer((byte)(addr>>8));
  SPI.transfer((byte)(addr&0xFF)); //1nd byte of 3 byte address
  SPI.transfer((byte)(value>>16));  //2st byte of 3 byte data
  SPI.transfer((byte)(value>>8));
  SPI.transfer((byte)(value&0xFF));//3nd byte of 3 byte data
  digitalWrite(csPin, HIGH);
  SPI.endTransaction(); // Uncomment if you have uncommented SPI.beginTransaction()
  delay(writeCycle);
}

int eepromReadInt(int addr){
  byte MSB = 0;
  byte LSB = 0;
  int value = 0;
  SPI.beginTransaction(SPISettings(4000000, MSBFIRST, SPI_MODE0));
  digitalWrite(csPin, LOW);
  SPI.transfer(READ);
  SPI.transfer((byte)(addr>>16)); //1st byte of 3 byte address
  SPI.transfer((byte)(addr>>8));
  SPI.transfer((byte)(addr&0xFF));
  MSB = SPI.transfer(0x00); //store the first byte in MSB buffer
  LSB = SPI.transfer(0x00); //store the first byte in LSB buffer
  digitalWrite(csPin, HIGH);
  SPI.endTransaction();
  value = (int)((MSB<<8)|LSB);
  return value;
}