I2C_EEPROM_WRITE.ino

#include <Wire.h>

#define DEV_ADDR   0x57
#define START_ADDR 0x045C
#define LENGTH     4

void setup()
{
  Serial.begin(57600);
  Wire.begin();
  delay(1000);
  Serial.println("Ready!");
}

void loop()
{
  if(Serial.available() > 0)
  {
    char c = Serial.read();
    
    switch(c)
    {
      case 'r':
        i2c_read();
        break;
      case 'w':
        i2c_write_one();
        Serial.println("Done!");
        break;
      default:
        Serial.println("Error!");
        break;
    }
  }
}

void i2c_read()
{
  Wire.beginTransmission(DEV_ADDR);
  Wire.write((int)(START_ADDR >> 8)); // MSB
  Wire.write((int)(START_ADDR & 0xFF)); // LSB
  Wire.endTransmission();
  Wire.requestFrom(DEV_ADDR,LENGTH);

  while(Wire.available())
  {
    byte val = Wire.read();

    if(val < 0x10)
      Serial.print("0");

    Serial.print(val, HEX);
    Serial.print(" ");
  }
  
  Serial.println();
}

void i2c_write_one()
{
  Wire.beginTransmission(DEV_ADDR);
  Wire.write((int)(START_ADDR >> 8)); // MSB
  Wire.write((int)(START_ADDR & 0xFF)); // LSB
  Wire.write(0);
  Wire.write(0);
  Wire.write(0);
  Wire.write(1);
  Wire.endTransmission();
}