#include <TinyWire.h>

#define LED 7 // LED connected to Digital Pin 7

byte student_1 = 1; //student addresses
byte student_2 = 2; //student addresses
byte student_3 = 3; //student addresses

void setup() {
pinMode( LED, OUTPUT); // intializing LED
TinyWire.begin(); // intializing Communication
}

void loop() {

// Sync Teacher and first student
digitalWrite(LED,HIGH);                 // led turns on
TinyWire.beginTransmission(student_1);  // begin transmission to student 1 board
TinyWire.send('y');                     // Sending a message
TinyWire.endTransmission();             // ending the transmission

delay(1000);                            // wait for a second

digitalWrite(LED,LOW);                  // led turns off
TinyWire.beginTransmission(student_1);  // begin transmission to student board
TinyWire.send('n');                     // Sending a message
TinyWire.endTransmission();             // ending the transmission

delay(1000);                            // wait for a second

// Sync Teacher and second student
digitalWrite(LED,HIGH);                 // led turns on
TinyWire.beginTransmission(student_2);  // begin transmission to student 1 board
TinyWire.send('y');                     // Sending a message
TinyWire.endTransmission();             // ending the transmission

delay(1000);                            // wait for a second

digitalWrite(LED,LOW);                  // led turns off
TinyWire.beginTransmission(student_2);  // begin transmission to student board
TinyWire.send('n');                     // Sending a message
TinyWire.endTransmission();              // ending the transmission

delay(1000);                            // wait for a second

// Sync Teacher and third student
digitalWrite(LED,HIGH);                 // led turns on
TinyWire.beginTransmission(student_2);  // begin transmission to student 1 board
TinyWire.send('y');                     // Sending a message
TinyWire.endTransmission();             // ending the transmission

delay(1000);                            // wait for a second

digitalWrite(LED,LOW);                  // led turns off
TinyWire.beginTransmission(student_2);  // begin transmission to student board
TinyWire.send('n');                     // Sending a message
TinyWire.endTransmission();              // ending the transmission

delay(1000);                            // wait for a second
}

}