Hariharan Subramanian

#include <Wire.h>

 

const int ledGreenPin = 12;

const int ledRedPin = 10;

String msgFromMaster = "";

 

void setup() {  

​

           Wire.begin(8);                // join i2c bus with address #8  

           Wire.onReceive(readFromMasterEvent);     // register event when there is data received from master   

           Wire.onRequest(writeToMasterEvent); // register event when there is a request by master    

 

          Serial.begin(9600);//added by hari  

 

          pinMode(ledGreenPin, OUTPUT);  

          pinMode(ledRedPin, OUTPUT);    

 

          digitalWrite(ledGreenPin, LOW);  

          digitalWrite(ledRedPin, HIGH);

}

 

void loop() {  

          delay(5000);

}

 

// function that executes whenever data is requested by master. this function is registered as an event, see setup()

void writeToMasterEvent() {  

     String msgToSend = "Hi, did u say '" + msgFromMaster + "'?"; //WORKING CODE  

     Wire.write(msgToSend.c_str());

}

 

void readFromMasterEvent(int howMany) {    

​

     String currentMessage = "";  

​

     while (Wire.available()){    

           char c = Wire.read();    

           if(c == 0x00){

                break;    

           }else if(c == 0x01){//Indicates a message started arriving from master    

           }else{

                 msgFromMaster = msgFromMaster + c;      

                 currentMessage = currentMessage + c;      

 

                 //Serial.print("Plain Character: "); Serial.println(c);

                //Serial.print("In Binary: "); Serial.println(c,BIN);

                //Serial.print("In Oct: "); Serial.println(c,OCT);

                //Serial.print("In Decimal: "); Serial.println(c,DEC);

                //Serial.print("In Hex: "); Serial.println(c,HEX);

                //Serial.print(msgFromMaster);

                //Serial.println("---");    

            }  

      }

​

      Serial.print("Msg received from master: ");

      Serial.println(msgFromMaster);  delay(10000);

 

}