Tangible User Interfaces - Fall 2011

Description

Use the Arduino to control a set of lights using as input the keyboard.

Components Used

• Light Emitting Diode (LED)x3
• Resistorx3

Arduino 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
 
 
 * Command structure is "<colorCode>*X", where "colorCode" is
 * one of "r","g",or "b" and "x"" is the number of times the colorCode was hitted,  every keystroke represents a 10% of increment in that light
 * E.g. "rr" Red =20%
 *      "bbb" Blue = 30%
 *
 * Adapted on  September 13 2011, based on the code
 * 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 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

int countRed = 0;    //counter of number of "r's" pressed
int countGreen = 0;   //counter of number of "g's" pressed
int countBlue = 0;  //counter of number of "b's" pressed
int index = 0;  // index to traverse the array
int redValue = 0;
int greenValue = 0;
int blueValue = 0;
char value ;

void setup() {
  pinMode(redPin,   OUTPUT);   // sets the pins as output
  pinMode(greenPin, OUTPUT);   
  pinMode(bluePin,  OUTPUT);
  Serial.begin(9600);
//  analogWrite(redPin,   127);   // set them all to mid brightness
//  analogWrite(greenPin, 127);   // set them all to mid brightness
//  analogWrite(bluePin,  127);   // set them all to mid brightness
  Serial.println("enter color command (e.g. 'rrrr' (will set RED at 40%) :");  
}

void loop () {
  // clear the string
  memset(serInString, 0, 100);
  //read the serial port and create a string out of what you read
  readSerialString(serInString);

 
  value = serInString[index];
  if (value == 'r' && countRed <=10){
      countRed++;
      index++;
  }
  else if(value == 'g' && countGreen <=10){
      countGreen++;
      index++;
  }
  else if(value =='b' && countBlue <=10) {
      countBlue++;
      index++;
  }

  redValue = 25*countRed;      // 25 is aprox 10% increment in brightness
  greenValue = 25*countGreen;
  blueValue = 25*countBlue;

      analogWrite(redPin, redValue);
      analogWrite(greenPin, greenValue);
      analogWrite(bluePin, blueValue);
 
   
 
  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++;
  }
}