Zap Zap

So I have been drooling over this open source micro controller called the arduino for 2 weeks, and last night I finally went out with talia and got one :) along with a whole bunch of goodies like LEDs, resistors, and transisters

I spent a good 2 hours playing around with it and getting some LEDs to turn on and pulse and stuff.

First I simply wrote a piece of code to turn on  the on-board LED every second for 1 second, then turn it off for 2 seconds

Code:

 // this will be the pin for the onboard led :)
int ledPin1 = 13;

 void setup()
 {
   pinMode(ledPin1, OUTPUT);
 }

 void loop()
 {
   digitalWrite(ledPin1, HIGH);  // turn the led on
   delay(1000);  // wait for 1S
   digitalWrite(ledPin1, LOW); // turn the led off
   delay(2000);  // wait for 2S
 }


Then I plugged in an external LED into the same pin as the on-board LED and watched it blink along with the on-board LED (no pics, sorry)

Then I wanted to plug a whole bunch of LEDs into a breadboard and blink them using a different pin than the on-board LED. This required the addition of a resister. In this test I had 3 LEDs, the first is connected to the on-board LED and the other two are connected to 2 other pins using resisters. I wanted to explore what the difference would be with different resisters so I had 1 LED connected in series with a 470 ohm resister and the other with a 4.7k resister

Code:

 // this will be the pin for the onboard led :)
int ledPin1 = 13;

int LEDPin2 = 2;// this will be the led with a 470 ohm resister
int LEDPin3 = 4;// this will be the led with a 4.7k ohm resister

 void setup()
 {
   // set the onboard led pin to an output pin
   pinMode(ledPin1, OUTPUT);
   pinMode(LEDPin2, OUTPUT);
   pinMode(LEDPin3, OUTPUT);
}

void loop()
{
   digitalWrite(ledPin1, HIGH);  // turn the led on
   // I want the new resister leds to blink out of phase with the onboard LED
   digitalWrite(LEDPin2, LOW);  // turn the led on
   digitalWrite(LEDPin3, LOW);  // turn the led on
   delay(1000);  // wait for 1S
   digitalWrite(ledPin1, LOW); // turn the led off
   digitalWrite(LEDPin2, HIGH);  // turn the led on
   digitalWrite(LEDPin3, HIGH);  // turn the led on
   delay(2000);  // wait for 2S
}

The final thing I wanted to do was have an LED pulse its brightness. I did that using a pulse width modulated digital pin which alters its voltage based on the the value you give it.

code:

int PMWLEDPin = 3;


void setup()
{
    pinMode(PMWLEDPin, OUTPUT);
}

 void loop()
 {
  for(int i = 0;i <= 255; i = i + 10)
  {
    analogWrite(PMWLEDPin, i);  // turn the led on
    delay(10);
  }
  for(int i = 255;i >= 0; i = i - 10)
  {
    analogWrite(PMWLEDPin, i);  // turn the led on
    delay(10);
  }
  analogWrite(PMWLEDPin, 0);
  delay(100);
}


I don't have pictures for that last one but it worked very nicely.

One of the things that I have noticed is that I have forgotten a LOT of my high school physics so I have to go and review all of that. If anyone can recommend a good webpage that goes over all of that basic stuff I would really appreciate it :)

As for the future, I have a couple projects in mind. I think I'm going to try and build a sentry gun from team fortress 2 :)

~(' ')~