Serial.println displays nothing

Other Hardware Displays
1

Hello.
I have successfully tested several Arduino componants (leds, 8x8 matrix, buzzer) but the command println never worked. Why ?

void setup(){
  Serial.begin(9600);
  Serial.println("The program starts ...");
}
2

Welcome to the forum

Which Arduino board are you using ?
What baud rate is the Serial monitor set to ?
Do you see anything if you reset the board with the Serial monitor open ?
What, if anything, is connected to the board ?

3

I use the card Arduino Uno.
I don't know what the baud rate is or how to find it.
If the "Serial monitor" is the window "Output" in the Arduino IDE, yes, I see this when I compile : "Le croquis utilise 3176 octets (9%) de l'espace de stockage de programmes. Le maximum est de 32256 octets.
Les variables globales utilisent 355 octets (17%) de mémoire dynamique, ce qui laisse 1693 octets pour les variables locales. Le maximum est de 2048 octets."
For the moment, the device connected is the 4x4 keyboard, which is the reason why I need to display values.

And I'm using a PC with Windows 11.

4

Disconnect everything from the Uno

Upload this sketch to the Uno


void setup()
{
  Serial.begin(9600);
}

void loop()
{
  Serial.println("Hello World");
  delay(1000);
}

Open the Serial monitor and check its baud rate, bottom right of the screen (assuming IDE 1.8.something)
image

If it is not set to 9600 baud then change it
What do you see in the Serial monitor window ?

1 Like
5

I found the Serial monitor tab. Actually, it was not "Output". I was on the wrong tab.
It works. Your program displays something.
Trying with mine, now.

6

Nice ! It works.
Sorry for this neebie question. I was just not watching the right window.
Thank you very much !

7

I am glad it works

Good luck with your project

8

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.