====== Communication série Arduino/Processing ======


Il est très facile d'envoyer une valeur avec la communication série, mais il souvent utile d'envoyer un paquet de valeurs. Par exemple envoyer les valeurs de deux ou plus capteurs.

===== Code Arduino =====
<code cpp>
// Send serial data to Processing
// Data are separated by a ",", so you could send any number of data

int firstSensor = 0;    // first analog sensor
int secondSensor = 255;   // second analog sensor

void setup() {
  Serial.begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only
  }
}

void loop() {

    // Update Data with linear values
    firstSensor += 1; 
    secondSensor -= 1;
    if (secondSensor < 0)  secondSensor = 255;
    if (firstSensor > 255)  firstSensor = 0;
    
    // Send Data
    Serial.print(firstSensor);
    Serial.print(","); // séparateur
    // Avec println on ferme le paquet de valeur, car "ln"
    Serial.println(secondSensor); 
    
    // Sampling rate
    delay(5);
}
</code>


===== Code Processing =====

<code java>
// Get Serial Data from an Arduino
// Parse it with a separator caracter ","

// import the Processing serial library
import processing.serial.*;    
Serial myPort; // The serial port

// Test values
int v1 =0;
int v2 = 255;
int x;

void setup() {
  size(640,480);
  // Open serial port
  //printArray(Serial.list());
  myPort = new Serial(this, Serial.list()[0], 9600);

  // Read bytes into a buffer until you get a linefeed (ASCII 10):
  myPort.bufferUntil('\n');

  //draw with smooth edges:
  //smooth();
  background(255);
}

void draw() {

  // Draw circles
  fill(#ff0000);
  ellipse(x, v1, 5, 5);
  fill(#00ff00);
  ellipse(x, v2, 5, 5);
 
  // Update x position
  x++;
  
  // Refresh screen
  if (x > 600) {
    background(255);
    x = 0;
  }
}

// serialEvent  method is run automatically by the Processing applet
// whenever the buffer reaches the byte value set in the bufferUntil()
// method in the setup():
void serialEvent(Serial myPort) {

  // read the serial buffer:
  String myString = myPort.readStringUntil('\n');
  
  // if you got any bytes other than the linefeed:
  myString = trim(myString);
  
  // split the string at the commas
  // and convert the sections into integers:
  int values[] = int(split(myString, ','));

  if (values.length > 0) {
    v1 = values[0];
    v2 = values[1];
    //println(v2);
  }
}
</code>