/*  
*   PulseSensor 
*/

int PulseSensorPurplePin = A0;        // Analog for arduino A0 or ADC ESP8266
int Signal;                           // holds the incoming raw data. Signal value can range from 0-1024
int Threshold = 550;                  // Determine which Signal to "count as a beat", and which to ingore.

// The SetUp Function:
void setup() {
   Serial.begin(9600);         // Set's up Serial Communication at certain speed.
}

int counter=0;
int last_counter=0;
int last_state_counter=0;

void loop() {

  Signal = analogRead(PulseSensorPurplePin);  // Read the PulseSensor's value.

  if(Signal >= Threshold && last_state_counter==0)
  {  
    last_state_counter=1;
    counter++;
  } 
  else if(Signal < Threshold && last_state_counter==1) 
  {
    last_state_counter=0;               
  }

  if(counter!=last_counter)
  {
    last_counter=counter;
    Serial.println(counter);
  }
  delay(100);

}