/*
Fireplace
Turns a series of LED arrays on and off at random intervals.
PWM is used to vary the brightness of some arrays at random 
intervals. There are not enough PWM outputs for all the arrays, 
so some are simply switched on and off
 */

const int pwm1 = 3; // define our output pins
const int pwm2 = 5;
const int pwm3 = 6;
const int pwm4 = 9;
const int pwm5 = 10;
const int pwm6 = 11;

const int io2 = 2; // these pins do not provide PWM
const int io4 = 4;
const int io7 = 7;

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize the PWM pins as outputs.
  digitalWrite(pwm1, LOW);    // turn the LED off by making the voltage LOW
  pinMode(pwm1, OUTPUT);
  digitalWrite(pwm2, LOW);    // turn the LED off by making the voltage LOW
  pinMode(pwm2, OUTPUT);
  digitalWrite(pwm3, LOW);    // turn the LED off by making the voltage LOW
  pinMode(pwm3, OUTPUT);
  digitalWrite(pwm4, LOW);    // turn the LED off by making the voltage LOW
  pinMode(pwm4, OUTPUT);
  digitalWrite(pwm5, LOW);    // turn the LED off by making the voltage LOW
  pinMode(pwm5, OUTPUT);
  digitalWrite(pwm6, LOW);    // turn the LED off by making the voltage LOW
  pinMode(pwm6, OUTPUT);

  digitalWrite(io2, LOW);    // turn the LED off by making the voltage LOW
  pinMode(io2, OUTPUT);
  digitalWrite(io4, LOW);    // turn the LED off by making the voltage LOW
  pinMode(io4, OUTPUT);
  digitalWrite(io7, LOW);    // turn the LED off by making the voltage LOW
  pinMode(io7, OUTPUT);
  
  // we will be sending random durations and random intensity levels to 
  // the various LED boards to flicker the 'flames'
  randomSeed(analogRead(0));  // generate a random seed
}

// the loop function runs over and over again forever
void loop() {
int rnd;

// set random intensity levels for the LED boards 
// controlled by PWM outputs
rnd = random(1,256);
analogWrite(pwm1,rnd);
rnd = random(1,256);
analogWrite(pwm2,rnd);
rnd = random(1,256);
analogWrite(pwm3,rnd);
rnd = random(1,256);
analogWrite(pwm4,rnd);
rnd = random(1,256);
analogWrite(pwm5,rnd);
rnd = random(1,256);
analogWrite(pwm6,rnd);

// randomly turn on or off the LED boards controlled
// by standard I/O pins
if (random(0,2)){digitalWrite(io2, HIGH);} else {digitalWrite(io2, LOW);}
if (random(0,2)){digitalWrite(io4, HIGH);} else {digitalWrite(io4, LOW);}
if (random(0,2)){digitalWrite(io7, HIGH);} else {digitalWrite(io7, LOW);}

// pause for a random interval to display these light levels
// in the fireplace
delay(random(200,2000));
}