/*
Why is the interupt not working?

[email protected]
*/




int ledPin = PC13;  // PC13 = LED built-in at bluepill
uint8_t irq_pin = PB9;
void setup() {     
  Serial.begin(115200);                           
  pinMode(ledPin, OUTPUT);
  pinMode(irq_pin, INPUT); //INPUT_PULLUP

  attachInterrupt(digitalPinToInterrupt(irq_pin),buttonPressed,CHANGE);      
  
  digitalWrite(irq_pin, HIGH); //  function for creating external interrupts
}

void loop() //  void loops runs continuously
{  }

void buttonPressed()                                              //
{                    
 digitalWrite(ledPin, !digitalRead(ledPin));
 Serial.println("Now in IRQ.");
}





/*
int ledPin    = LED_BUILTIN;
uint8_t buttonPin = PB9;
int LED       = PB12;

void setup() {
  Serial.begin(115200);
  pinMode(ledPin, OUTPUT);
  pinMode(buttonPin, INPUT);
  pinMode(LED, OUTPUT);
  interrupts();
  //attachInterrupt(digitalPinToInterrupt(buttonPin), ISR, CHANGE );
  attachInterrupt(digitalPinToInterrupt(buttonPin), ISR, FALLING );

  digitalWrite(ledPin, LOW);
  digitalWrite(LED, LOW);
  Serial.println("Exit setup...");
  ISR();
}

void loop() {
  if (digitalRead(buttonPin) == LOW)  {
    digitalWrite(LED, HIGH);  
//    digitalWrite(ledPin, LOW);
  }
  else {
    digitalWrite(LED, HIGH);
//    digitalWrite(ledPin, HIGH);
    delay(100);
    digitalWrite(LED, LOW);
//    digitalWrite(ledPin, LOW);
    delay(100);
  }
}

void ISR() {
  Serial.println("In ISR now.");
  digitalWrite(ledPin, LOW);
  //digitalWrite(ledPin, LOW);
}
*/