Arduino : Sleep_Fade Project part 2

I tested my project with the Kids and changed some things.

• Removed : TIP120
• Removed : LED Ring
• Added : 4 Super bright LED
• Added : A USB connector

To reduce size and cost, I removed the LED Ring and use 4 LED instead. Since this doesn't need too much power I removed the TIP120.
I added a USB connector so they can charge a MP3 player on it.

How it works:

• Red button activate the reading time and the LEDs
• After 15 minutes the LEDs blink and the buzzer alert that it's time to stop reading
• The 4 LEDs slowly fade until Off (set to 90 minutes)
• The blue button reset the Fade Off to 90 minutes.

Next steps :

• Modification to the USB connector to help charging devices (some need the data line)
• Code modification
• Maybe a reset switch or I will use the 2 buttons at the same time.....

Code:

/*
TimedFader
Will wait for X minutes before fading the Output

Nicolas Gravel
nicgravel@gmail.com

V. 1.0.2
July 3rd, 2011
*/

// constants won't change. They're used here to 
// Use only ATtiny85 or Arduino pins initialisation

// set pin numbers: ATtiny85
const int MainLED =  0;      // Main LED + TIP120 for External light
const int Buzzer = 1;        // Piezo
const int Button1 = 2;       // Main button Start the waiting time before Fading Time
const int StatusLED = 3;     // Heartbeat LED
const int Button2 = 4;       // Start or Reset the Fading Timer.

// Set pin number : Arduino
/*
const int MainLED =  11;     // Main LED + TIP120 for External light
const int Buzzer = 12;       // Piezo
const int Button1 = 7;       // Main button Start the waiting time before Fading Time
const int StatusLED = 13;    // Heartbeat LED
const int Button2 = 8;       // Start or Reset the Fading Timer.
*/
// 5minutes=300, 15 minutes=900, 60 minutes=3600, 90minutes=5400, 120minutes=7200
// variables will change:

int TimeToWait = 900;        // -> How many seconds before the FadeOut will start <- Can be adjust
int TimeFade = 5400;         // -> On how many seconds the FadeOut will be        <- Can be adjust

int TimeWait = -5;           // Waiting Timer
int TimeFadeLeft = 0;        // Time Left in the FadeOut process
int Interval = 5000;         // HeartBeat delay
long PreviousMillis = 0;     // will store last time we enter the Loop ( each second)          
int Ledstate = LOW;          // Used for the Hartbeat LED. This help for blink from Mostly ON or OFF

void setup() {
  // initialize the OUTPUT pin:
  pinMode(MainLED, OUTPUT);      
  pinMode(StatusLED,OUTPUT);
  pinMode(Buzzer,OUTPUT);
  // initialize the pushbutton pin as an input:
  pinMode(Button1, INPUT);
  pinMode(Button2,INPUT);
 //Serial.begin(9600);
}


void loop(){

  // read the state of the pushbutton value:
  if(digitalRead(Button2)==LOW) //I have a NC button instead of a NO
  { // Button2 will only reset FadceOut Timer
    TimeWait = -2;
    StartFadeOut();
  }

  if(digitalRead(Button1)==HIGH)
  { //Button1 Start Waiting Time before FadeOut Timer
    TimeWait = TimeToWait;
    digitalWrite(Buzzer,HIGH);
    StartFadeOut();
  }
  else
  { // Turn Buzzer Off
    digitalWrite(Buzzer,LOW);
  }  

  unsigned long currentMillis = millis();
  if(currentMillis - PreviousMillis > Interval)
  {
    PreviousMillis = currentMillis;   
    //Serial.println(TimeWait);
    if(Ledstate==LOW)
    { // Blink Status LED. StatusLED will be mostly ON When in Waiting time
      // or mostly off when Fading or when done.
      digitalWrite(StatusLED,HIGH);
      delay(50);
      digitalWrite(StatusLED,LOW);
    }
    else
    {
      digitalWrite(StatusLED,LOW);
      delay(50);
      digitalWrite(StatusLED,HIGH);
    }
    
    if(TimeWait == 0)
    {
      // Mostly Done waiting. Turn StatusLED Off
      Ledstate=(LOW);
      digitalWrite(StatusLED,LOW);
      TimeWait--;
    }
    else if(TimeWait > 0)
    {
      //Waiting ....
      TimeWait--;
    }
    
    else if(TimeWait == -1)
    {
      //Done Waiting. 
      TimeWait--;
      MainFlash();
    }
    else if (TimeWait == -5)
    {
      //Startup State do nothing please
    }
    else
    {
     //Fading OUT Started
     Ledstate=LOW;
     if(TimeFadeLeft > -1)
     {
       int x;
       x = map(TimeFadeLeft, 0, TimeFade, 0, 255); //Map the LED value (0-255) to the TimeFade (0-xx)
       //Serial.print("Fade X now is : ");
       //Serial.println(x);
       //Serial.print("Fade Left is : ");
       //Serial.println(TimeFadeLeft);
       analogWrite(MainLED,x);
       TimeFadeLeft--;
      }
      else
      {
        //All done ! StatusLED blink only every 5 sec.
        Interval=5000;
      }
    }
  }   
}


void StartFadeOut()
{
  //FadeOut initialization
  Ledstate = HIGH;
  TimeFadeLeft=TimeFade;
  analogWrite(MainLED,255);
  digitalWrite(StatusLED,HIGH);
  Interval = 1000;
}

void MainFlash()
{
  // Flash MainLED and Buzzer 3 Times.
  for (int i=0; i <= 2; i++)
  {
    analogWrite(MainLED, 0);   // set the LED OFF
    digitalWrite(Buzzer,HIGH);
    delay(100);              // wait 
    analogWrite(MainLED, 255);    // set the LED ON
    digitalWrite(Buzzer,LOW);
    delay(100);
  }
}