The Coding Couple

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Creation Crate Month 1: An Arduino powered Mood Lamp

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Tinkering with microcontrollers has been on my “to try” list for quite some time.  I recently stumbled upon Creation Crate.  Creation Crate is a monthly tech education subscription box.   Each month you receive a Arduino UNO R3 and parts to complete a project. The instruction book includes the source code for the project.  The source code is licensed under the GNU General Public License.  Each month the projects increase in difficulty.  I thought Creation Crate would be a wonderful way to get my feet with wet with Arduino and programming electronics.

I was on the fence about signing up for the subscription box because I was not sure what to expect.  I intend to write a blog post for each Creation Crate I receive in case there is a reader out there on the fence like I was.

The Project

The project for month one is creating a mood lamp! The mood lamp changes colors and only turns on when it’s dark.

An Arduino powered mood lamp

An Arduino powered mood lamp

What’s in the Box

Inside of month one’s box we have:

  • Arduino UNO R3
  • Breadboard
  • USB Cable
  • Chinese Paper Latern
  • U-shaped Jumper wires
  • Regular Jumper wires
  • 2.2k OHM Resistor
  • a blue, red and green LED
  • Light Dependent Resistor (LDR)
This month's contents

Month one’s contents

Building the Hardware

The setting up the hardware was pretty simple.  The instruction book includes nice illustrations for connecting the hardware together.

Adding the LEDs, resistor and light dependent resistor

Adding the LEDs, resistor and light dependent resistor

Connecting the jumper wires

Connecting the jumper wires

Connecting the Arduino

Connecting the Arduino

Powering it up

Powering it up

Programming

Source code for the project is included in the instruction book.  Typing the sketch file was pretty straight forward. I did make one significant error when I tried to upload the sketch on the Arduino:  I selected the wrong port in the Arduino IDE.  I was stuck on this error for more time than I care to admit. (Doh! Never again!)

// License: GNU General Public License
// Creation Crate: Month 1 - Mood Lamp
int pulseSpeed = 1;
int ldrPin = 0; // LDR (Light Dependent Resistor) in Analog 0
int redLed = 11;
int greenLed = 10;
int blueLed = 9;
int ambientLight; // light value in the room
int power = 150;
float RGB[3];
float CommonMathVariable = 180/PI;
void setup() {
// put your setup code here, to run once:
// tells the UNO R3 to send data out to the LEDs
pinMode(redLed, OUTPUT);
pinMode(greenLed, OUTPUT);
pinMode(blueLed, OUTPUT);
// sets all the outputs to LOW (off)
digitalWrite(redLed, LOW);
digitalWrite(greenLed, LOW);
digitalWrite(blueLed, LOW);
}
void loop() {
// put your main code here, to run repeatedly:
for(float x = 0; x < PI; x = x + -.00001) {
// red LED
RGB[0] = power * abs(sin(x * (CommonMathVariable)));
// green LED
RGB[1] = power * abs(sin((x + PI/3) * (CommonMathVariable)));
// blue LED
RGB[2] = power * abs(sin((x + (2 * PI) / 3) * (CommonMathVariable)));
ambientLight = analogRead(ldrPin);
if(ambientLight > 600) {
analogWrite(redLed, RGB[0]);
analogWrite(greenLed, RGB[1]);
analogWrite(blueLed, RGB[2]);
}
else {
digitalWrite(redLed, LOW);
digitalWrite(greenLed, LOW);
digitalWrite(blueLed, LOW);
}
// Calculate the delay for each color depending on color
// brightness; brighter LEDs will change colour slower
for(int i = 0; i < 3; i++) {
if(RGB[i] < 1) {
delay(20 * pulseSpeed);
}
else if (RGB[i] < 5) {
delay(10 * pulseSpeed);
}
else if (RGB[i] < 10) {
delay(2 * pulseSpeed);
}
else if (RGB[i] < 100) {
delay(1 * pulseSpeed);
}
else {}
}
delay(1);
}
}
view raw mood_lamp.ino hosted with ❤ by GitHub

Final Thoughts

Creation Crate Month 1: An Arduino powered mood lamp

Creation Crate Month 1: An Arduino powered mood lamp

This was my first experience programming an Arduino board and I loved it!  The instruction book leaves out a lot of beginner details like, “what’s a resistor” or explaining the parts that make up an Arduino board, but I think that’s okay.  When I finished the project I was finally motivated to sit down and start reading my Getting Started with Arduino book.