show on the screen

Hi, I want to know how to show an analogic nput value on the screen

As a graph?
As a number?
As an angle?

Open the example sketch in the arduino software. It gives you everything you need. In the setup section, add Serial.begin(9600); In the main loop, add Serial.println(val); after your analog read. That should get you started.

I`ve made this:

int n;
void setup(){
  Serial.begin(9600);
}
void loop(){
  n=analogRead(3);
  Serial.println(n);
  delay(3000);
}

It doesn't show anything in the screen.

I also dont understand the println instruction. It refers to the computer serial port or to the board serial port TX,RX?

My arduino duemilanove is connected to the computer by the USB port, and the TX,RX pins are not connected to the computer. I want to show the value in the computer screen, not in a LCD screen

You have to open the Serial monitor from the Arduino IDE and set it to the correct Baud rate.

The Serial.println command tells the computer to print and then do a carriage return. This is so you don't have all of your data packed together with no spaces or line spaces.

Probably, you haven't turned on your serial monitor in the arduino environment. (see link below) It is the square box icon at the top of the screen. When you hover your mouse over it, it will tell you what it is. When you open the serial monitor, it opens serial communication with your arduino and prints whatever the arduino sends the PC. Make sure your comm rate is set to 9600, since you setup the serial to 9600 in your sketch.

Your reading will be between 0 and 1023. If there is nothing connected, you will probably see the value change as the pin would be floating. If you have a potentiometer connected, you should see the value change as you turn the pot.

Hope this helps.

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