/* Serial call-and-response
by Tom Igoe (with adjustments by Dan)

Sends a byte out the serial port, and reads 1 byte in.
sets x location a rect

Updated October 12, 2004
*/

int xpos;                    // x location of rectangle
BFont font;

//change this value for different sensors
byte response = 2;
 
void setup() {
  //begin serial communication
  beginSerial();
  size(255, 200);
  font = loadFont("Garamond-Bold.vlw.gz");
  //start off our call and response by sending the value stored in response;
  serialWrite(response);
}

void loop() {
  
  //draw background with red value from sensor
  background(0,0,0);
  textFont(font, 44);
  fill(255);
  //display rotation value
  text(xpos, 5, 30);
  
  fill(0,0,255);
  rectMode(CENTER_DIAMETER);
  rect(xpos,100, 50, 50);
  
}

void serialEvent() {
  //receive byte
  xpos = (int) serial;
  //send # back to ask for another one
  serialWrite(response);
}