I've just been tinkering with the first couple of projects in the Arduino starter kit, and decided to turn the lamp above the Arduino off so that I could see the lights flashing in the dark.
To my surprise when I did this, one loop of the following program (a modification of Project 2) was run.
// global variables
int switchstate = 0;
//setup
void setup(){
// outputs
pinMode(3,OUTPUT);
pinMode(4,OUTPUT);
pinMode(5,OUTPUT);
// inputs
pinMode(2,INPUT);
}
void loop(){
// read value of pin 2
// either HIGH or LOW
switchstate = digitalRead(2);
// if the button is not pressed
if (switchstate == LOW) {
digitalWrite(3, LOW); // turn the green LED on pin 3 on
digitalWrite(4, LOW); // turn the red LED on pin 4 off
digitalWrite(5, LOW); // turn the red LED on pin 5 off
}
// if the button is pressed
else {
digitalWrite(3, HIGH);
delay(250);
digitalWrite(3, LOW);
digitalWrite(4, HIGH);
delay(250);
digitalWrite(4, LOW);
digitalWrite(5, HIGH);
delay(250);
digitalWrite(5, LOW);
}
}
Later, as I was writing this post, when I turned the lamp on, it occured again.
What could be possibly causing this?
Heat from the lamp above the Arduino?
