#define BUTTON_PIN PA0
#define LED_PIN PC13

bool lastButtonState = HIGH;

void setup()
{
  pinMode(BUTTON_PIN, INPUT_PULLUP);
  pinMode(LED_PIN, OUTPUT);

  // Blue Pill LED OFF
  digitalWrite(LED_PIN, HIGH);

  Serial.begin(115200);

  Serial.println("STM32_READY");
}

void loop()
{
  bool buttonState = digitalRead(BUTTON_PIN);

  // BUTTON PRESSED
  if (buttonState == LOW && lastButtonState == HIGH)
  {
    digitalWrite(LED_PIN, LOW);

    Serial.println("LED_ON");

    delay(50);
  }

  // BUTTON RELEASED
  if (buttonState == HIGH && lastButtonState == LOW)
  {
    digitalWrite(LED_PIN, HIGH);

    Serial.println("LED_OFF");

    delay(50);
  }

  lastButtonState = buttonState;
}