Serial read loop not reading \n

Using Arduino Programming Questions
#1

I am new to Arduino and C. I have writeen a sketch to check, whether a year is a leap year.
In order to allow user input I have added a function to read the serial monitor, like so:

int ReadLine(char str[]) {
  char c;
  int index = 0;
  
  while (true) {
    
    if (Serial.available() > 0) {
      c = Serial.read();
      
      Serial.print("Received char: ");
      Serial.println(c, HEX);
      
      if (c != '\n') {
        Serial.print("Debug (ReadLine | if > char): ");
        Serial.println(c);
        str[index++] = c;
      } else {
        Serial.print("Debug (ReadLine | if > else): ");
        Serial.println(c);
        str[index] = '\0';       // null termination character
        break;
      }
      
      Serial.print("Debug (ReadLine | str): ");
      Serial.println(str);
      Serial.print("Debug (ReadLine | index): ");
      Serial.println(index);
    }
  }
  
  return index;
}

The problem is that I never reach the ‘else’ part when checking for the new line character.
Entering: 2012, I expect to see with Serial.println(c, HEX) the output as: 32 30 31 32 0D 0A, with oD being the \n terminator.

I have not added input validation or other fancy stuff (and am aware the sketch loops forever to read the serial port), I simply wanted to understand serial.read to build bigger projects.

What am I doing wrong in this sketch?

Any help appreciated.

#2

IIRC the IDE never sends an '\n' as it is the trigger to know when to send.

you could try to replace the \n with # instead and see if that works...

#3

Thanks, this was quick…

Changing the condition to use ‘#’ or ‘x’ does produce a different result; it will enter the ‘else’ part. Great.

However, is there a way to use the key as line terminator for this function?
Why is

      Serial.print("Received char: ");
      Serial.println(c, HEX);

not repeating the or more so the hex 0D (\n) character?

Re-reading your answer: what is it sending then?
I can enter one or two or more numbers, and nothing happens. But once I hit the input is read.

#4

Can't you just change the line ending option on the serial monitor?

#5

@AWOL: Hmm, I am using the IDE 1.0.5 and can't seem to find this option in the preferences or elsewhere.
Where can I change this?

My previous question still stands: why is Serial.Read() not reading the '\n\ or maybe Serial.print() can't display it?

#6

It's in the serial monitor.

#7

Ouch... this hurts!!
Thanks AWOL! This is most embarrassing...
This ends three hours of pulling my hair out :astonished:

#8