blink

hi. i'm new with all of this i am trying use 3 LEDs in sequence.
int LEDpin=11; //select a digital I/O pin
int LEDpin1=12;
int LEDpin2=13;

void setup()
{

pinMode(LEDpin, OUTPUT); //set the digital I/O pin to OUTPUT mode

}

void loop()
{
// void loop() {
digitalWrite(LEDpin, HIGH); //set pin 11 output to HIGH, about 5v
delay(1000); //delay 1000ms, or 1 second
digitalWrite(LEDpin, LOW); //set pin 11 output to low, 0v
delay(3000); // delay 3000ms, or 3 second
digitalWrite(LEDpin1, HIGH);
delay(1000);
digitalWrite(LEDpin1, LOW);
delay(2000);
digitalWrite(LEDpin2, HIGH);
delay(1000);
digitalWrite(LEDpin2, LOW);
delay(1000);
}

that is my code. the reason i am stuck is because the the LED on pin 12 is very did work. Please help me

BRODY_GILLOTT:
the reason i am stuck is because the the LED on pin 12 is very did work.

The reason I cannot understand you is, because the sentence doesn't make sense.

If you also want to use LEDs on EDpin1 and LEDpin2 you better set those pins to pinMode OUTPUT in the setup() function, too!

Sorry my question was not clear. I am new and trying to learn the Arduino Uno. I have done the blink Sketch tutorial and wanted to add three other LED's. The sequence works but the LED's on pin 12 and pin 13 is very dim compared to the other LED's.I don't under stand what you mean by "If you also want to use LEDs on LEDpin1 and LEDpin2 you better set those pins to pinMode OUTPUT in the setup() function, too!"

I don’t under stand what you mean by “If you also want to use LEDs on LEDpin1 and LEDpin2 you better set those pins to pinMode OUTPUT in the setup() function, too!”
[/quote]

I mean: By defalut, all pins on your Arduino are set to INPUT.

If you want to use three pins for LED output, you will have to set three pins to OUTPUT, not just one.

Perhaps:

void setup() 
{
  
  
  pinMode(LEDpin, OUTPUT); //set the digital I/O pin to OUTPUT mode
  pinMode(LEDpin1, OUTPUT); //set the digital I/O pin to OUTPUT mode
  pinMode(LEDpin2, OUTPUT); //set the digital I/O pin to OUTPUT mode
}

If you leave a pin at pinMode (INPUT, which is default, then this will happen:

digitalWrite(LEDpin2, HIGH);

This line will activate the “internal pull-up” resistor on the INPUT pin.

With the 8-bit Atmega controllers, the "internal pull-up resistor is a value in the range 20K to 50K.

This pull-up resistor will limit the current through your LED, so it will just glow very dim.

An INPUT pin with the internal pull-up resistor activated is NOT enough to make a LED shining bright.

If you want a bright shining LED on a pin, set the pin to pinMode OUTPUT first, then digitalwrite the pin to HIGH!

Thank you very much. You have helped me alot!