Arduino Programming Questions

What is the correct function to set a pin as an output in Arduino?

• pinMode(13, INPUT)

• digitalWrite(13, HIGH)

• pinMode(13, OUTPUT)

• analogWrite(13, HIGH)

Why won’t the following "blink" code work?

• The LED will not blink because there is no LOW state.

• delay(1000); is too short.

• The pin should be set to INPUT.

• The function digitalWrite should be analogWrite.

What common mistake might prevent the built-in LED on pin 13 from blinking?

• Forgetting to declare pinMode(13, OUTPUT); in setup().

• Using delay(0); instead of delay(1000);

• Writing digitalRead(13, HIGH); instead of digitalWrite(13, HIGH);

• Using analogWrite(13, 255); instead of digitalWrite(13, HIGH);

If your LED stays on instead of blinking, what could be the problem?

• The LED might be broken.

• The code is missing digitalWrite(13, LOW); and a delay.

• pinMode(13, OUTPUT); is not needed.

• The delay time is too long.

What will happen if you write delay(-1000);?

• The Arduino will blink the LED faster.

• The delay function will be ignored.

• The Arduino will enter an infinite loop.

• The code will not compile.

Why won’t the following code fade an LED properly?

• The loop should count down after reaching 255.

• pinMode(9, OUTPUT); should be INPUT.

• The delay is too long.

• The pin should be 13, not 9.

What type of pins support analogWrite() for fading LEDs?

• Digital pins

• Only pin 13

• PWM pins marked with ~ *

• Any pin set to OUTPUT

What is the range of values accepted by analogWrite()?

• 0 to 255 *

• 0 to 1023

• 0 to 100

• 0 to 50

What common error occurs if you try to fade an LED on pin 2?

• Nothing will happen because pin 2 doesn’t support PWM.

• The LED will turn on and off instantly.

• The code won’t compile.

• The LED will still fade but slower.

What happens if you use digitalWrite(9, HIGH); instead of analogWrite(9, 255);?

• The LED will fade smoothly.

• The LED will not light up.

• The LED will turn on at full brightness.

• The LED will blink instead of fade.