/*
 *      This sketch is for an RGB LED with "common cathode"
 *      (+ on R, G and B pins, 1 common pin to ground)
 *      ex. image: https://curiousart.org/eprojects/RGB_LEDsm.jpg
 *      -It does color cycling/fading on PWM pins
 *      Setup:
 *        - Wire each PWM pin thru a 330 ohm resistor to R,G and B
 *        - Wire LED Gnd pin to Gnd
 *  (For board hookup example, see: https://curiousart.org/eprojects/RGB_layout.jpg)
 */

int Rpin = 9; //-- can be any 3 PWM pins choosing from: 3,5,6,9,10,11
int Bpin = 10;
int Gpin = 11;

void setup() {
pinMode(Rpin, OUTPUT);
pinMode(Gpin, OUTPUT);
pinMode(Bpin, OUTPUT);
//-- Start with all LEDs off
analogWrite(Rpin, 0);
analogWrite(Gpin, 0);
analogWrite(Bpin, 0);
}

void loop() {
    for(int i = 255; i > 0; i = i - 1) {   //-- Green fade down
    analogWrite(Gpin, i);
    delay(7);
   }
    for(int i = 0; i < 255; i++) { //-- Red fade up
    analogWrite(Rpin, i);
    delay(7);
   }
   for(int i = 255; i > 0; i = i -1) {  //-- Blue fade down
    analogWrite(Bpin, i);
    delay(7);
   }
   for(int i = 0; i < 255; i++) {   //-- Green fade up
    analogWrite(Gpin, i);
    delay(7);
   }
   for(int i = 0; i < 255; i++) {    //-- Blue fade up
    analogWrite(Bpin, i);
    delay(7);
   }
    for(int i = 255; i > 0; i = i - 1) {   //-- Red fade down
    analogWrite(Rpin, i);
    delay(7);
   }
}