Firefly10

/*
  Modified May 18, 2017. [email protected], v1.0 firefly blinking green LEDs
  For Digispark ATTiny85 and clones.
  Fade in and out LEDs for random on and off times. This uses PWM and analogwrite().
  Attach 120ohm resistor to ground/GND. Put positive leg of LEDs on different holes
  like P0 as labeled on the board.
*/
/* pin names and C code values
 *  onboard LED=1
 *  p0=0 (PWM)
 *  p1=1 (PWM)
 *  p2=2
 *  p3=3
 *  p4=4 (PWM)
 *  p5=do not use
 */
// Do includes here


//=================================================================
//=================================================================
//=================================================================

// Begin global vars.
//int p0=1; //onboard LED

byte p0=0; //Pin labeled p0 on actual board.
byte LEDONBOARD=1;
byte p1=1; //Same as LEDONBOARD.
byte p2=2;
byte p3=3;
byte p4=4;
byte mypauseup=30; //milliseconds between steps to light up an LED. Increase to make LED light up slower.
byte mypausedn=mypauseup/2; //ms between steps to dim an LED.
byte randon; //random number to light LED in milliseconds.
byte randoff; //random ms to turn off led.
byte lightlevel; //light level when LED on. 10-255
byte randpos=0;
const byte NUMPINS=3;
byte myPins[NUMPINS] = {p0, p1, p4};
byte usepin;
int randwait;

//Declare subs here.
//=================================================================
void allpinsoff()
{
  byte k;
  for (k=0; k<NUMPINS; k++)
    {
      analogWrite(myPins[k],0); // Turn off pin.
    }
    return;
}
// the setup function runs once when you press reset or power the board
void setup() {
  // initialize 4 pins as an output.
  byte k=0;
  for (k=0; k<NUMPINS; k++)
    {
    pinMode(myPins[k], OUTPUT);
    analogWrite(myPins[k], 0); //Turn off LED.
    }
  allpinsoff();
}

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

  randon=random(500,800); //Time to leave led on. Range 50-1000ms.
  //randoff=random(500,1000);
  lightlevel=random(200,255); //Light intensity of LED.

  randpos=random(0,(NUMPINS-1));
  usepin=myPins[randpos];
  fadein(usepin,lightlevel,mypauseup);
  delay(randon); //Keep light on for randon ms.
  fadeout(usepin,lightlevel,mypausedn); //start at lightlevel and go to zero.
  allpinsoff;
  //delay(randoff);

  //Wait random seconds while led is off.
  randwait=random(1000,5000); //wait 2-5 seconds between blinks.
  delay(randwait); //Wait in ms.


}
//=================================================================
//Simple Fade LED in from 0 to valin.
/*Parms:
 * LED: led number on board.
 * valin: PWM value to light LED, 0-255.
*/
void fadein(byte LED, byte valin, byte pauseup)
{
int i;
for (i=0; i<valin; i++)
  {
  analogWrite(LED,i);
  delay(pauseup); //pause between steps when turning up LED.
  }
}
//=================================================================
/*
 * Fade given LED from oldval to zero.
 */
void fadeout(byte LED, byte oldval, byte pausedn)
{
  int i;
  for (i=oldval; i>0; i--)
    {
      analogWrite(LED,i);
      delay(pausedn);
    }
}