#include <TinyWireS.h>      //library for Attiny as slave
    
int x=0;

void setup()
{
  TinyWireS.begin(6); // start i2c network as slave
  TinyWireS.onRequest(requestEvent);
  pinMode(PB3, OUTPUT);           // Turn on LED when program starts
  digitalWrite(PB3, HIGH);
  delay(1000);
  digitalWrite(PB3,LOW);
  delay(1000);
  digitalWrite(PB3, HIGH);
  delay(1000);
  digitalWrite(PB3,LOW);
  delay(1000);
}

void loop()
{
  TinyWireS_stop_check();
} 

// Gets called when the ATtiny receives an i2c request
void requestEvent()
{ 
  TinyWireS.send(x);        //send a byte over to master
  x++;
}