source: rtos_arduino/trunk/arduino_lib/libraries/Ciao/examples/CiaoCommandXMPP/CiaoCommandXMPP.ino@ 136

/*

 This sketch uses the xmpp connector to receive command for the MCU from a xmpp client.

 Possible commands to send from the xmpp client:

 * "digital/PIN"        -> to read a digital PIN
 * "digital/PIN/VALUE"  -> to write a digital PIN (VALUE: 1/0)
 * "analog/PIN/VALUE"   -> to write in a PWM PIN(VALUE range: 0 - 255);
 * "analog/PIN"         -> to read a analog PIN
 * "servo/PIN/VALUE"    -> to write angle in a SERVO PIN(VALUE range: 0 - 180);
 * "mode/PIN/VALUE"     -> to set the PIN mode (VALUE: input / output)
 * "led on"             -> turn on led 13
 * "led off"            -> turn off led 13
 * "ciao"               -> random answers in 5 different languages
 
 NOTE: be sure to activate and configure xmpp connector on Linino OS
       http://labs.arduino.org/Ciao
   
 created September 2015
 by andrea[at]arduino[dot]org
 
 */
 
#include <Ciao.h>
#include <Servo.h>

Servo servo;

void setup() {

  Ciao.begin();
}

void loop() {

  CiaoData data = Ciao.read("xmpp");   
  if(!data.isEmpty()){  
    String id = data.get(0);
    String sender = data.get(1);
    String message = data.get(2);
    
    message.toUpperCase();
    
    if(message == "LED ON"){
      digitalWrite(13,HIGH);
      Ciao.writeResponse("xmpp",id,"Led D13 ON");
    }
    
    else if(message == "LED OFF"){
      digitalWrite(13,LOW);
      Ciao.writeResponse("xmpp",id,"Led D13 OFF");     
    }       
    else{
      String command[3];
          
      splitString(message,"/",command,3);
      execute(command,id);
    }
  }
}

void execute(String cmd[], String id) {

  if (cmd[0] == "DIGITAL") {
    digitalCommand(cmd,id);
  }
  else if (cmd[0] == "ANALOG") {
    analogCommand(cmd,id);
  }
  else if (cmd[0] == "SERVO") {
    servoCommand(cmd,id);
  }
  else if (cmd[0] == "MODE") {
    setMode(cmd,id);
  }
  else
    Ciao.writeResponse("xmpp",id,"sorry, i don't understand :(");
}

void servoCommand(String cmd[], String id){
   int pin, value;
  
  pin = (cmd[1]).toInt();
  
  if (cmd[2] != "-1") {
    value = (cmd[2]).toInt();
    if(value <= 180 && value >=0){
      servo.attach(pin);
      servo.write(value);
      Ciao.writeResponse("xmpp",id,"Servo D"+String(pin)+" set to "+String(value)+" degrees");
    }
    else
      Ciao.writeResponse("xmpp",id,"Invalid angle value");
  }
  else
    Ciao.writeResponse("xmpp",id,"Invalid command");  
}

void digitalCommand(String cmd[], String id) {
  int pin, value;
  
  pin = (cmd[1]).toInt();
  
  if (cmd[2] != "-1") {
    value = (cmd[2]).toInt();
    digitalWrite(pin, value);
    if (value == 1)
      Ciao.writeResponse("xmpp",id,"Pin D"+String(pin)+" ON");
    else if(value == 0)
      Ciao.writeResponse("xmpp",id,"Pin D"+String(pin)+" OFF");   
  }
  else if (cmd[2] == "-1") {
    value = digitalRead(pin);
    Ciao.writeResponse("xmpp",id,"D"+String(pin)+" value = "+String(value));
  }
}

void analogCommand(String cmd[], String id) {
  int pin, value;

  pin = (cmd[1]).toInt();
  
  if (cmd[2] != "-1") {
    value =(cmd[2]).toInt();
    analogWrite(pin, value);
    Ciao.writeResponse("xmpp",id,"D"+String(pin)+" set to analog");
  }
  else if (cmd[2] == "-1") {
    value = analogRead(pin);
    Ciao.writeResponse("xmpp",id,"A"+String(pin)+" value = "+String(value));
  }
}

void setMode(String cmd[], String id) {
  int pin;

  pin = (cmd[1]).toInt();
  
  if (cmd[2] == "INPUT") {
    pinMode(pin, INPUT);
    Ciao.writeResponse("xmpp",id," pin D"+String(pin)+" set in INPUT mode");
    return;
  }

  if (cmd[2] == "OUTPUT") {
    pinMode(pin, OUTPUT);
    Ciao.writeResponse("xmpp",id," pin D"+String(pin)+" set in OUTPUT mode");
    return;
  }
  Ciao.writeResponse("xmpp",id,"invalid mode");
}