#include <Firmata.h>

byte analogPin;

void analogWriteCallback(byte pin, int value) {
  pinMode(pin,OUTPUT);
  analogWrite(pin, value);
}

void setup() {
  Firmata.setFirmwareVersion(0, 1);
  Firmata.attach(ANALOG_MESSAGE, analogWriteCallback);
  Firmata.begin();
}

void loop() {
  while(Firmata.available()) {
    Firmata.processInput();
  }
  for(analogPin = 0; analogPin < TOTAL_ANALOG_PINS; analogPin++) {
    Firmata.sendAnalog(analogPin, analogRead(analogPin));
  }
}