Processing nabız ölçer yapımında hata

// Nabız Ölçer
import processing.serial.*;
Serial myPort; // The serial port
int xPos = 1; // horizontal position of the graph
float oldHeartrateHeight = 0; // for storing the previous reading

void setup () {
// set the window size:
size(600, 400);
frameRate(25);

// List available serial ports.
println(Serial.list());

// Setup which serial port to use.
// This line might change for different computers.
myPort = new Serial(this, Serial.list()[1], 9600);

// set inital background:
background(0);
}

void draw () {
}

void serialEvent (Serial myPort) {
// read the string from the serial port.
String inString = myPort.readStringUntil('\n');

if (inString != null) {
// trim off any whitespace:
inString = trim(inString);
// convert to an int
println(inString);
int currentHeartrate = int(inString);

// draw the Heartrate BPM Graph.
float heartrateHeight = map(currentHeartrate, 0, 1023, 0, height);
stroke(0,255,0);
line(xPos - 1, height - oldHeartrateHeight, xPos, height - heartrateHeight);
oldHeartrateHeight = heartrateHeight;
// at the edge of the screen, go back to the beginning:
if (xPos >= width) {
xPos = 0;
background(0);
} else {
// increment the horizontal position:
xPos++;

}
}
}

/*  Getting_BPM_to_Monitor prints the BPM to the Serial Monitor, using the least lines of code and PulseSensor Library.
*  Tutorial Webpage: [URL='https://pulsesensor.com/pages/getting-advanced']Getting (Calculating) BPM:[/URL]
*
--------Use This Sketch To------------------------------------------
1) Displays user's live and changing BPM, Beats Per Minute, in Arduino's native Serial Monitor.
2) Print: "♥  A HeartBeat Happened !" when a beat is detected, live.
2) Learn about using a PulseSensor Library "Object".
4) Blinks LED on PIN 13 with user's Heartbeat.
--------------------------------------------------------------------*/

#define USE_ARDUINO_INTERRUPTS true    // Set-up low-level interrupts for most acurate BPM math.
#include <PulseSensorPlayground.h>     // Includes the PulseSensorPlayground Library.  

//  Variables
const int PulseWire = 1;       // PulseSensor PURPLE WIRE connected to ANALOG PIN 0
const int LED13 = 13;          // The on-board Arduino LED, close to PIN 13.
int Threshold = 550;           // Determine which Signal to "count as a beat" and which to ignore.
                               // Use the "Gettting Started Project" to fine-tune Threshold Value beyond default setting.
                               // Otherwise leave the default "550" value.
                              
PulseSensorPlayground pulseSensor;  // Creates an instance of the PulseSensorPlayground object called "pulseSensor"


void setup() {  

  Serial.begin(9600);          // For Serial Monitor

  // Configure the PulseSensor object, by assigning our variables to it.
  pulseSensor.analogInput(PulseWire);  
  pulseSensor.blinkOnPulse(LED13);       //auto-magically blink Arduino's LED with heartbeat.
  pulseSensor.setThreshold(Threshold);  

  // Double-check the "pulseSensor" object was created and "began" seeing a signal.
   if (pulseSensor.begin()) {
    Serial.println("We created a pulseSensor Object !");  //This prints one time at Arduino power-up,  or on Arduino reset. 
  }
}



void loop() {

int myBPM = pulseSensor.getBeatsPerMinute();  // Calls function on our pulseSensor object that returns BPM as an "int".
                                               // "myBPM" hold this BPM value now.

if (pulseSensor.sawStartOfBeat()) {            // Constantly test to see if "a beat happened".
Serial.println("♥  A HeartBeat Happened ! "); // If test is "true", print a message "a heartbeat happened".
Serial.print("BPM: ");                        // Print phrase "BPM: "
Serial.println(myBPM);                        // Print the value inside of myBPM.
}

  delay(20);                    // considered best practice in a simple sketch.

}