MSP430G2553 Interfacing with DS1307

Here Iam interfacing DS1307 with msp430g2553 in Energia 0101E0011 , using "wire.h" .
The hour, minute ,and second is displayed on energia serial monitor.The remaining can be easily added.
The output can displayed on LCD if it is interfaced with this .

The common mistake everyone encounter with ds1307 and msp430 is that ds1307 is working in minimum 4.5 volt max 5v and msp430g2553 is low power max 3.5v. Here I changed the pullup voltage to 3.5 volt for ds1307 and vcc is 5v and also low power for msp430.
http://datasheets.maximintegrated.com/en/ds/DS1307.pdf this is the ds1307 datasheet.
The code is added below.

///////////////////////////////// 

#include "Wire.h"                 //for DS1307 I2C

#include <string.h>

#include <math.h>

#define DS1307_I2C_ADDRESS 0x68

byte second, minute, hour, dayOfWeek, dayOfMonth, month, year;

void setup()

{

  Wire.begin();

  Serial.begin(9600);

  /*

  //////here programmer set the current time ,from where the ds runs

  */

   second = 45;

   minute = 30;

   hour = 16;

   dayOfWeek = 5;

   dayOfMonth = 20;

   month = 3;

   year = 12;

   setDateDs1307(second, minute, hour, dayOfWeek, dayOfMonth, month, year);

}

void loop()

{

 getDateDs1307(&second, &minute, &hour, &dayOfWeek, &dayOfMonth, &month, &year);///to get current time from ds1307

 timedisplay();

}

void timedisplay()                 ///////////Function to display current time

{

  Serial.print(hour, DEC);

  Serial.print(":");

  Serial.print(minute, DEC);

  Serial.print(":");

  Serial.print(second, DEC);

  Serial.println("  ");

  delay(1000);

}

void getDateDs1307(byte *second,   // Gets the date and time from the ds1307

                   byte *minute,

                   byte *hour,

                   byte *dayOfWeek,

                   byte *dayOfMonth,

                   byte *month,

                   byte *year)

{

  // Reset the register pointer

  Wire.beginTransmission(DS1307_I2C_ADDRESS);

  Wire.write(0);

  Wire.endTransmission();

  Wire.requestFrom(DS1307_I2C_ADDRESS, 7);

  // A few of these need masks because certain bits are control bits

  *second     = bcdToDec(Wire.read() & 0x7f);

  *minute     = bcdToDec(Wire.read());

  *hour       = bcdToDec(Wire.read() & 0x3f);  // Need to change this if 12 hour am/pm

  *dayOfWeek  = bcdToDec(Wire.read());

  *dayOfMonth = bcdToDec(Wire.read());

  *month      = bcdToDec(Wire.read());

  *year       = bcdToDec(Wire.read());

}

void setDateDs1307(byte second,        // 0-59         ///to set time in ds1307

                   byte minute,        // 0-59

                   byte hour,          // 1-23

                   byte dayOfWeek,     // 1-7

                   byte dayOfMonth,    // 1-28/29/30/31

                   byte month,         // 1-12

                   byte year)          // 0-99

{

   Wire.beginTransmission(DS1307_I2C_ADDRESS);

   Wire.write(0);

   Wire.write(decToBcd(second));    // 0 to bit 7 starts the clock

   Wire.write(decToBcd(minute));

   Wire.write(decToBcd(hour));      // If you want 12 hour am/pm you need to set

                                   // bit 6 (also need to change readDateDs1307)

   Wire.write(decToBcd(dayOfWeek));

   Wire.write(decToBcd(dayOfMonth));

   Wire.write(decToBcd(month));

   Wire.write(decToBcd(year));

   Wire.endTransmission();

}

// Convert normal decimal numbers to binary coded decimal

byte decToBcd(byte val)

{

  return ( (val/10*16) + (val%10) );

}

// Convert binary coded decimal to normal decimal numbers

byte bcdToDec(byte val)

{

  return ( (val/16*10) + (val%16) );

}

 The circuit is below