0

I have a very basic script that is supposed to display something to the serial monitor but no matter what I try the serial monitor won't display anything...I;ve watched about 5 tutorials now and each one has failed to display anything. Any ideas what I'm doing wrong?

Here is my code:

char rx_byte;

void setup() {
  Serial.begin(115200);
  pinMode(13, OUTPUT);
  digitalWrite(13, LOW);
}

void loop() {
  if(Serial.available() > 0){
    rx_byte = Serial.read();
    Serial.print("You typed: ");
    Serial.println(rx_byte);
    digitalWrite(13, HIGH);
    delay(1000);
    digitalWrite(13, LOW);
  }
}
13
  • Are you typing anything into the serial monitor? What baud rate is the serial monitor set to?
    – Nick Gammon
    Commented Feb 19, 2016 at 8:29
  • I'm typing just the number 1 and 0, according to the tutorial I watched that should turn the LED on/off. The baud rate is set the same as what is in my code.
    – mr-matt
    Commented Feb 19, 2016 at 17:37
  • I'm typing just the number 1 and 0 - and then you pressed the Send button? Please add Serial.println ("Hello, world"); after the Serial.begin line and see if that appears in the serial monitor.
    – Nick Gammon
    Commented Feb 19, 2016 at 20:31
  • Yes then I pressed the send button. I tried putting that line in after Serial.begin and still nothing...
    – mr-matt
    Commented Feb 19, 2016 at 20:42
  • Well, solve that first. No point typing and pressing Send if nothing appears. What Arduino do you have? What version of the IDE?
    – Nick Gammon
    Commented Feb 19, 2016 at 20:43

3 Answers 3

2

Which one are you using?

The one closest to the reset button, I believe its the native...

This is more confusing than I realized. The Due has two ports:

Due ports


Programming port

For programming, the programming port is easiest to use. And you can "talk" to the serial port using Serial, like this:

void setup ()
  {
  Serial.begin (115200);
  Serial.println ("Hello, world!");
  }  // end of setup

void loop ()
  {
  }  // end of loop

Native USB port

This lets you emulate USB devices (eg. keyboard, mice). However if you want to use it for Serial communications you need to use a different class SerialUSB like this:

void setup ()
  {
  SerialUSB.begin(115200);
  while (!SerialUSB) ; // wait for it to become ready
  SerialUSB.println ("Starting ...");
  }  // end of setup

unsigned long i;

void loop ()
  {
  SerialUSB.print ("Hello, world! Count = ");
  SerialUSB.println (++i);
  delay (1000);
  }  // end of loop

It also helps to wait for the serial port to become ready, as I did in setup. Otherwise you may miss the first 10 lines or so of serial output.

1

You have to change the baud rate at the right bottom corner of the serial monitor to 115200 which you have assigned initially. I have tested it and It doesn't matter if its int/char

1
  • I have done that, still no luck.
    – mr-matt
    Commented Feb 19, 2016 at 17:36
0

Try replacing the line char rx_byte; with int rx_byte=0;. Use Serial.println(rx_byte,DEC);

int rx_byte=0;

void setup() {
  Serial.begin(115200);
  pinMode(13, OUTPUT);
  digitalWrite(13, LOW);
}

void loop() {
  if(Serial.available() > 0){
    rx_byte = Serial.read();
    Serial.print("You typed: ");
    Serial.println(rx_byte,DEC);
    digitalWrite(13, HIGH);
    delay(1000);
    digitalWrite(13, LOW);
  }
}
1
  • Same again, nothing...
    – mr-matt
    Commented Feb 19, 2016 at 17:37

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.