Tangible User Interfaces - Fall 2011

My diffuser is made of a ping pong ball, with a bit of filling to even out the light. 

Code for the stepper is below: It's not 100% perfect, but it does the job ! :) 

 

/* 

 * 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;

int colorVal;

int rcolorVal;

int gcolorVal;

int bcolorVal;

 

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() {

  pinMode(redPin,   OUTPUT);   // sets the pins as output

  pinMode(greenPin, OUTPUT);   

  pinMode(bluePin,  OUTPUT);

  Serial.begin(9600);

  analogWrite(redPin,   50);   // set them all to mid brightness

  analogWrite(greenPin, 50);   // set them all to mid brightness

  analogWrite(bluePin,  50);   // set them all to mid brightness

  Serial.println("enter color command (e.g. 'r43') :");  

}

 

void loop () {

  // clear the string

  memset(serInString, 0, 100);

  //read the serial port and create a string out of what you read

  readSerialString(serInString);

    

  colorCode = serInString[0];

  if( colorCode == 'r' || colorCode == 'g' || colorCode == 'b' ) {

    colorVal = atoi(serInString+1);

  

    Serial.print("setting color ");

    Serial.print(colorCode);

    Serial.print(" to ");

    Serial.print(colorVal);

    Serial.println();

    

   

    

    serInString[0] = 10;                   // indicates we've used this string

    if(colorCode == 'r' && colorVal == 0) {

        colorVal = (rcolorVal + 25);

        analogWrite(redPin, colorVal);

        rcolorVal = (rcolorVal + 25);

     }

       else if(colorCode =='r' && colorVal >1){

        analogWrite(redPin, colorVal);

        rcolorVal == colorVal;

       }

  

    if(colorCode == 'g' && colorVal == 0) {

        colorVal = (gcolorVal + 25);

        analogWrite(greenPin, colorVal);

        gcolorVal = (gcolorVal + 25);

     }

       else if(colorCode =='g' && colorVal >1){

        analogWrite(greenPin, colorVal);

        gcolorVal == colorVal;

       }

    if(colorCode == 'b' && colorVal == 0) {

        colorVal = (bcolorVal + 25);

        analogWrite(bluePin, colorVal);

        bcolorVal = (bcolorVal + 25);

     }

       else if(colorCode =='b' && colorVal >1){

        analogWrite(bluePin, colorVal);

        bcolorVal == colorVal;

       }

      

      

   //color states

   

   Serial.print("red is at ");

    Serial.print(rcolorVal);

    Serial.println();

    

    Serial.print("green is at ");

    Serial.print(gcolorVal);

    Serial.println();

    

    Serial.print("blue is at ");

    Serial.print(bcolorVal);

    Serial.println();

  

  }

  

    

  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++;

  }

}