#include <Wire.h>

const int ds_address = 0xB0 >> 1; //DS1077 default address
const byte freq_pin = 7; //read frequency on this pin

void setup() {
  Wire.begin();
  
  Serial.begin(9600);
  pinMode(freq_pin, INPUT);
  
  // the line below writes to the MUX register
  // see the app note for clarifying this value
  //i2c_write(ds_address, 0x02, 0xF9, 0x00);
  // the line below writes to the DIV register
  // the bits valued at 987 are the hex values
  // taken from the DS1077 REG spread sheet
  //i2c_write(ds_address, 0x01, 0x98, 0x70);
}

void loop() {
  // read the frequency 
  Serial.println(getFrequency(freq_pin));
}

void i2c_write(int device, byte address) {
     Wire.beginTransmission(device); //start transmission to device 
     Wire.write(address);        // send register address
     Wire.endTransmission(); //end transmission
}

void i2c_write(int device, byte address, byte val1) {
     Wire.beginTransmission(device); //start transmission to device 
     Wire.write(address);        // send register address
     Wire.write(val1);        // send value to write
     Wire.endTransmission(); //end transmission
}

void i2c_write(int device, byte address, byte val1, byte val2) {
     Wire.beginTransmission(device); //start transmission to device 
     Wire.write(address);        // send register address
     Wire.write(val1);        // send value to write
     Wire.write(val2);        // send value to write
     Wire.endTransmission(); //end transmission
}

long getFrequency(int pin) {
  #define SAMPLES 4096
  long freq = 0;
  for(unsigned int j=0; j<SAMPLES; j++)
    freq+= 500000/pulseIn(pin, HIGH, 250000);
  return freq / SAMPLES;
}