Assignment: Digital I/O with Arduino Boards + Diffuser

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Assignment: Digital I/O with Arduino Boards + Diffuser
Collaborators:

Assignment: Digital I/O with Arduino Boards + Diffuser

3 LEDs w/ Diffusion and Serial Commands

Donna Leo

I experimented with various diffusing materials.  The packing shell from class created a nice even diffusion.  I tried to use a small glass, and a plastic container, but wasn’t able to find the correct size or the lights shined through too clearly.  I eventually used the opaque top from a deodorant bottle.  I put poly-stuffing material inside the plastic top, and placed that on top of the 3 LEDs.  It created a nice even diffusion.  The photos upload are from the last attempt.

Mode1: Downloaded code to allow serial input.

* 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

*

Mode 2: If the user enters multiple values for a given color, each letter corresponds to 10% brightness (25), so rr = brightness of 50, rrg = brightness 50 red, 25 green.

Mode 3: The code controls the colors produced by the LEDs by typing in the color name "violet" or "emerald" or “orange.”

Components Used

• breadboard
• 3 220 Ohm resistors
• wires (yellow for pins to resistors toward LEDs, blue and black for ground)
• 3 LED (1 blue, 1 red, 1 green)
• Arduino board
• USB cable
• 1 rubber bands for stability
• For diffusion (poly-stuffing, plastic deodorant cap)

Modified Arduino Code

/*
* Serial RGB LED
* ---------------
* Serial commands control the brightness of R,G,B LEDs
* All 3 Modes work simultaneously
*
* Mode 1:
* 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
*
* Homework - Assignment 2
*
* Mode 2:
* Create alternate command structure: "<colorCode>*"
* each press of a letter corresponds to 10% brightness (25)
* so rr = brightness of 50, rrg = brightness 50 red, 25 green
*
* Mode 3:
* Create alternate command structure: "<color name>"
* enter "violet" it will produce the color violet
* enter "emerald" it will produce the color emerald
* enter "orange" and it will produce the color orange
*
* Created 18 October 2006
* copyleft 2006 Tod E. Kurt <tod@todbot.com
* http://todbot.com/
*
* Used the code by Aylin Selcukoglu as a template
*
* Modified 15 September 2009
* Donna Leo
*/

//include support for manipulating strings.
//for a useful string comparison function, see the bottom of this file... stringsEqual()
#include <stdio.h>
#include <string.h>

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;
char valTwo = 0;
int colorVal = 0;

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 redVal = 0;
int blueVal = 0;
int greenVal = 0;

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
redVal = 127;
analogWrite(greenPin, 127);   // set them all to mid brightness
greenVal = 127;
analogWrite(bluePin,  127);   // set them all to mid brightness
blueVal = 127;
Serial.println("enter color command, valid formats: 'r066', 'bbgr', 'violet', 'emerald' or 'orange') :"); 
}

void loop () {
//read the serial port and create a string from the input
readSerialString(serInString);  // store in array serInString

// with MODE 1 and MODE 2 colorCode will be r, g, or b
// with MODE 3 colorCode can be any character string spelling a color

colorCode = serInString[0];

// with MODE 1 valTwo will be a number
// with MODE 2 valTwo will be r, g, or b
// with MODE 3 valTwo will be some character string spelling a color

valTwo = serInString[1];     

// if colorCode != r, g, or b then go to MODE 3, otherwise:
if( colorCode == 'r' || colorCode == 'g' || colorCode == 'b' ) {

// if the second char = r, g or b then MODE 2:
if ( valTwo == 'r' || valTwo == 'g' || valTwo == 'b' || valTwo == '\0' ) {

int x = 0;
// while string still has new data (not null)
while ( serInString[x] != '\0' && x < 100 ){
colorCode = serInString[x];

// increase brightness of red by 10% (25)
if ( colorCode == 'r' ) {
redVal = (redVal + 25) % 255;
analogWrite(redPin, redVal);
Serial.print("color red set to ");
Serial.println(redVal);
}
// increase brightness of green by 10% (25)
else if ( colorCode == 'g' ) {
greenVal = (greenVal + 25) % 255;
analogWrite(greenPin, greenVal);
Serial.print("color green set to ");
Serial.println(greenVal);
}
// increase brightness of blue by 10% (25)
else if ( colorCode == 'b' ) {
blueVal = (blueVal + 25) % 255;
analogWrite(bluePin, blueVal);
Serial.print("color blue set to ");
Serial.println(blueVal);
}

// move to next character to evaluate
x++;     

}
}

// else, Mode 1:   
else {
colorVal = atoi(serInString+1);  // converts string to integer
Serial.print("setting color ");
Serial.print(colorCode);
Serial.print(" to ");
Serial.print(colorVal);
Serial.println();
serInString[0] = 0;                   // indicates we've used this string
if(colorCode == 'r') {
analogWrite(redPin, colorVal);
redVal = colorVal;
}
else if(colorCode == 'g') {
analogWrite(greenPin, colorVal);
greenVal = colorVal;
}
else if(colorCode == 'b') {
analogWrite(bluePin, colorVal);
blueVal = colorVal;
}
}
}

// else, MODE 3
else {
// make violet
if ( stringsEqual(serInString, "violet", 6) ) {
redVal = 140;
greenVal = 40;
blueVal = 230;
analogWrite(redPin, redVal);
analogWrite(bluePin, blueVal);
analogWrite(greenPin, greenVal);
Serial.println("setting color to violet ( r = 140, g = 040, b = 230)");
}  
// make emerald
if ( stringsEqual(serInString, "emerald", 7) ) {
redVal = 0;
greenVal = 210;
blueVal = 210;
analogWrite(redPin, redVal);
analogWrite(bluePin, blueVal);
analogWrite(greenPin, greenVal);
Serial.println("setting color to emerald (r = 0, g = 210, b = 210)");
}
// make emerald
if ( stringsEqual(serInString, "orange", 6) ) {
redVal = 200;
greenVal = 010;
blueVal = 010;
analogWrite(redPin, redVal);
analogWrite(bluePin, blueVal);
analogWrite(greenPin, greenVal);
Serial.println("setting color to orange (r = 200, g = 010, b = 010)");
}    
}

// reset variables
// colorVal = 0;

// reset string - prepare it for new input data
resetSerialString(serInString, 100);

delay(100);  // wait a bit, for serial data
}

// erase all data in string to make it fresh
void resetSerialString (char *strArray, int length) {
for (int i = 0; i < length; i++) {
strArray[i] = '\0';
}
}

// 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++;
}
}

//compare two strings to see if they are equal
//compares the first 'numCharacters' characters of string1 and string2 to
//see if they are the same
//
//E.g. stringsEqual("hello","hello",5) => true
//     stringsEqual("hello","helaabbnn",3) => true
//     stringsEqual("hello","helaa",5) => false

boolean stringsEqual(char *string1, char *string2, int numCharacters) {
if (strncmp(string1, string2, numCharacters) == 0) {
return true;
} else {
return false;
}
}

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