// Arduino slave three bytes

#include <Wire.h>
#include <Servo.h>
Servo myservo1; 
Servo myservo2;
int pos = 0;
byte i2c_rcv_opcode;
byte i2c_rcv_target;     // data received from I2C bus
byte i2c_rcv_value;     // data received from I2C bus
//byte i2c_send;    // confirmation

void setup(){
myservo1.attach(3);
myservo2.attach(13);
  
int inMin = 3; // Lowest output pin
int inMax = 13; // Highest output pin
for(int i=inMin; i<=inMax; i++)
{
   pinMode(i, OUTPUT);
}
 
  Wire.begin(0x08);           // join I2C bus as Slave with address 0x08
  
  // event handler initializations
  Wire.onReceive(dataRcv);    // register an event handler for received data
  Wire.onRequest(dataRqst);   // register an event handler for data requests
  
  // initialize global variables
    i2c_rcv_opcode = 255;
    i2c_rcv_target = 255;
    i2c_rcv_value = 255; 
 
 }

void loop(){

  
}

//received data handler function
void dataRcv(int numBytes){
  while(Wire.available()) { // read all bytes received
    
    i2c_rcv_opcode = Wire.read();
    i2c_rcv_target = Wire.read();
    i2c_rcv_value = Wire.read();

    }
    switch ( i2c_rcv_opcode) {
      case 100:
        digitalWrite(i2c_rcv_target,i2c_rcv_value) ;
    break;
      case 101:
        myservo1.write(i2c_rcv_value) ;
        delay(1000); 
    break;
      case 102:
        myservo2.write(i2c_rcv_value) ;
        delay(1000); 
    break;
    default:
      break;
  }
}

// requests data handler function
void dataRqst(){
  Wire.write(i2c_rcv_target); // send confirmation
  Wire.write(i2c_rcv_value); // send confirmation
  
}