#include <LiquidCrystal_I2C.h>

#define I2C_ADDR    0x27
#define LCD_COLUMNS 4
#define LCD_LINES   4

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);

int led = 13;
int buzzer = 12;


void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(13, OUTPUT); 
  pinMode(12, OUTPUT);

  // Init
  

    
}

void loop() {
  // put your main code here, to run repeatedly:
  int sensorValue = analogRead(A0);
  int counter=0;
 
for (int j = 0; j < 60000; j=j+2) {
  float A = 0.10;
  float onda = abs(A*sin(j * (PI/360)));
  Serial.println(onda);

  if(onda == A){
    int counter = counter + 1;
    digitalWrite(led, HIGH);
    tone(buzzer, 1000);
    delay(20);
    digitalWrite(led, LOW);
    noTone(buzzer);
    delay(20);

  }
// Print something
  lcd.init();
  lcd.backlight();
  lcd.setCursor(3, 0);
  lcd.print("BPM =");
  lcd.print(counter);
  
  

  

}

}