// Wire Master Reader
// by Nicholas Zambetti <http://www.zambetti.com>

// Demonstrates use of the Wire library
// Reads data from an I2C/TWI slave device
// Refer to the "Wire Slave Sender" example for use with this

// Created 29 March 2006

// This example code is in the public domain.


#include <Wire.h>

void setup()
{
  Wire.begin();        // join i2c bus (address optional for master)
  Serial.begin(9600);  // start serial for output
  writeMCP(0x6F, 0x01, 0x30); //Minutes
  writeMCP(0x6F, 0x02, 0x12); //Hora
  writeMCP(0x6F, 0x03, 0x03); //Day
  writeMCP(0x6F, 0x04, 0x26); //Date
  writeMCP(0x6F, 0x05, 0x06); //Month
  writeMCP(0x6F, 0x06, 0x13); //Year
  writeMCP(0x6F, 0x00, 0x45 | 0x80); //Year
}

byte readMCP(int deviceaddress, byte address ) {
  Wire.beginTransmission(deviceaddress);
  Wire.write(address);
  Wire.endTransmission();
  Wire.requestFrom(deviceaddress, 1);
  unsigned long time = millis();
  while (!Wire.available()) if ((millis() - time)>500) return 0x1F;
  return Wire.read();
}

void  writeMCP(int deviceaddress, byte address, byte time ) {
  Wire.beginTransmission(deviceaddress);
  Wire.write(address);
  Wire.write(time);
  Wire.endTransmission();
  delay(100);
}

void loop()
{
  Serial.println(readMCP(0x6F, 0x00)&0x7F, HEX);
  //Serial.println(F_CPU);

  delay(1000);
  
  
//  Wire.beginTransmission(4); // transmit to device #4
//  Wire.write("x is ");        // sends five bytes
//  Wire.write(x);              // sends one byte  
//  Wire.endTransmission();    // stop transmitting
//
//  x++;
//  delay(500);
}