Description:
I used an Arduino-Uno as a microprocessor to light three LED lights dependent on input from a keyboard. There are three different modes: ROYGBIV explicit color input, RGB explicit color input, or step-dimness color input. As a diffuser, I used a house that I 3D designed and printed from an Ultimaker 2+ out of PLA and ABS material, with some cotton distributed by the windows. The LEDs are capable of entering the house via the chimney.
Components Used:
- 1 Arduino
- 3 LEDs (red, green, and blue)
- 3 Resistor (220Ω)
- 1 Breadboard
- A keyboard
- A 3D printed house with holes in it.
- Cotton.
Code:
/*
* Serial RGB LED
* ---------------
* Serial commands control the brightness of R,G,B LEDs
*
* Command structure is "<colorCode><colorVal>", where "colorCode" is
* one of "r","g",or "b" and "colorVal" is a number 0 to 255.
* E.g. "r0" turns the red LED off.
* "g127" turns the green LED to half brightness
* "b64" turns the blue LED to 1/4 brightness
*
* Created 18 October 2006
* copyleft 2006 Tod E. Kurt <tod@todbot.com
* http://todbot.com/
*/
char serInString[100]; // array that will hold the different bytes of the string. 100=100characters;
// -> you must state how long the array will be else it won't work properly
char colorCode;
String colorCodeString; // necessary for first conditional check for ROYGBIV
float colorVal; // necessary for step-change conditional
int colorValInt; // necessary for clean println statements
float colorDuplicateInput; // necessary for computation of LED power
struct RGB { //instantiate a datastructure for RGB values
char colorName[50];
int r;
int g;
int b;
};
struct RGB variable[9]; // declare a variable array that contains data types of data structure RGB
int redPin = 9; // Red LED, connected to digital pin 9
int greenPin = 10; // Green LED, connected to digital pin 10
int bluePin = 11; // Blue LED, connected to digital pin 11
void setup() {
// ROYGBIV defined
strcpy(variable[0].colorName, "white");
variable[0].r = 255;
variable[0].g = 255;
variable[0].b = 255;
strcpy(variable[1].colorName, "red");
variable[1].r = 255;
variable[1].g = 0;
variable[1].b = 0;
strcpy(variable[2].colorName, "orange");
variable[2].r = 255;
variable[2].g = 165;
variable[2].b = 0;
strcpy(variable[3].colorName, "yellow");
variable[3].r = 255;
variable[3].g = 255;
variable[3].b = 0;
strcpy(variable[4].colorName, "green");
variable[4].r = 0;
variable[4].g = 255;
variable[4].b = 0;
strcpy(variable[5].colorName, "blue");
variable[5].r = 0;
variable[5].g = 0;
variable[5].b = 255;
strcpy(variable[6].colorName, "indigo");
variable[6].r = 75;
variable[6].g = 0;
variable[6].b = 130;
strcpy(variable[7].colorName, "violet");
variable[7].r = 238;
variable[7].g = 130;
variable[7].b = 238;
strcpy(variable[8].colorName, "black");
variable[8].r = 0;
variable[8].g = 0;
variable[8].b = 0;
pinMode(redPin, OUTPUT); // sets the pins as output
pinMode(greenPin, OUTPUT);
pinMode(bluePin, OUTPUT);
Serial.begin(9600); // instantiate communication between the computer and the microprocessor
analogWrite(redPin, variable[0].r); //default is R value for white
analogWrite(greenPin, variable[0].g); //default is G value for white
analogWrite(bluePin, variable[0].b); //default is B value for white
Serial.println("Please enter color command (e.g. r43, red, rrr) :");
}
void loop () {
// clear the string
memset(serInString, 0, 100);
//read the serial port and create a string out of what you read
readSerialString(serInString);
//this is basically catching everything...
if (atoi(serInString + 1) > 0 || atoi(serInString + 1) == 0) {
colorCodeString = String(serInString);
colorCode = serInString[0];
// check if we have the word in our dictionary
if( colorCodeString == "red" || colorCodeString == "green" || colorCodeString == "blue" || colorCodeString == "white" || colorCodeString == "black" || colorCodeString == "yellow" || colorCodeString == "orange" || colorCodeString == "violet" || colorCodeString == "indigo") {
for (int count = 0; count <= 8; count++) {
if(colorCodeString == variable[count].colorName) {
analogWrite(redPin, variable[count].r);
analogWrite(greenPin, variable[count].g);
analogWrite(bluePin, variable[count].b);
Serial.print("Setting RGB values for default ");
Serial.print(colorCodeString);
Serial.print(" hue: ");
String colorSentence_R = "R: " + String(variable[count].r);
String colorSentence_G = ", G: " + String(variable[count].g);
String colorSentence_B = ", B: " + String(variable[count].b);
Serial.println(colorSentence_R + colorSentence_G + colorSentence_B);
return;
}
}
}
// if not a full word in our dictionary...
else if (colorCode == 'r' || colorCode == 'g' || colorCode == 'b') {
// if not a step conditional but an explicit value
if (serInString[0] != serInString[1]) {
colorVal = atoi(serInString+1);
}
// the step conditional
else {
colorDuplicateInput = strlen(serInString);
colorVal = (float)(colorDuplicateInput/10 * 255.0);
}
colorValInt = (int)colorVal;
Serial.print("setting color ");
Serial.print(colorCode);
Serial.print(" to ");
Serial.print(colorValInt);
Serial.println();
serInString[0] = 0; // indicates we've used this string
if(colorCode == 'r')
analogWrite(redPin, colorValInt);
else if(colorCode == 'g')
analogWrite(greenPin, colorValInt);
else if(colorCode == 'b')
analogWrite(bluePin, colorValInt);
}
}
delay(100); // wait a bit, for serial data
}
//read a string from the serial and store it in an array
//you must supply the array variable
void readSerialString (char *strArray) {
int i = 0;
if(!Serial.available()) {
return;
}
while (Serial.available()) {
strArray[i] = Serial.read();
i++;
}
}