/*
Copyright 2011 Dustin L. Westaby

----------------------------------------------------------------------
        Prop Circuit for Attiny45
----------------------------------------------------------------------
Title:      cortana.c
Author:     Dustin Westaby
Date Created:   2/13/11
Last Modified:  2/13/11
Purpose:  Animated output to LEDs

Compiled with AVR-GCC WinAVR

Revisions List:
2/13/11 Initial Draft and test circuit


----------------------------------------------------------------------
        Fuses:
----------------------------------------------------------------------
 BrownOut Disabled
 CKDIV8
 Int RC Osc 8Mhz + 64ms

----------------------------------------------------------------------
        Inputs:
----------------------------------------------------------------------
 Power up

----------------------------------------------------------------------
        Ouputs:
----------------------------------------------------------------------
 pin        label       connections
----------------------------------------------------------------------
  2         PB3 =   LED
  3             PB4 =   LED
  5         PB0 =   LED
  6         PB1 =   LED
  7         PB2 =   LED

----------------------------------------------------------------------
        Notes:
----------------------------------------------------------------------
 -

*/

//--------------------------------------
//          Global Variables           |
//--------------------------------------
#define F_CPU 8000000UL/8  /* 8 MHz Internal Oscillator DIV8 */

enum { up, down };

//--------------------------------------
//              Includes               |
//--------------------------------------
#include <avr/io.h>
#include <util/delay.h>
//#include <avr/sleep.h>
#include <inttypes.h>


//--------------------------------------
//          Delay Subroutines          |
//--------------------------------------
void delay_ms(uint16_t ms) {
    while ( ms )
    {
        _delay_ms(1);
        ms--;
    }
}

void delay_us(uint16_t us) {
    while ( us )
    {
        _delay_us(1);
        us--;
    }
}

//--------------------------------------
//               Main                  |
//--------------------------------------
int main (void)
{

    //variables used for animations
    int i;
    i=0;

    int count_delay;
    count_delay=50;

    int duty_cycle;
    duty_cycle=1000;

    int direction;
    direction=up;

    //port B is an output
    DDRB =  0b00011111;

    //Spin Circle
    count_delay=50;
    for (i = 0; i < 4; i++)
    {
        PORTB = 0b00000001;
        delay_ms(count_delay);
        PORTB = 0b00000010;
        delay_ms(count_delay);
        PORTB = 0b00000100;
        delay_ms(count_delay);
        PORTB = 0b00001000;
        delay_ms(count_delay);
        PORTB = 0b00010000;
        delay_ms(count_delay);
    }

    //ALL ON
    PORTB = 0b00011111;
    delay_ms(800);

    //Blink Blink
    PORTB = 0b00000000;
    delay_ms(100);
    PORTB = 0b00011111;
    delay_ms(10);
    PORTB = 0b00000000;
    delay_ms(100);
    PORTB = 0b00011111;
    delay_ms(100);



    //starts brigth then dims (software PWM)
    int time_on, time_off, max_value,  min_value, rate_of_change;
    max_value=500;
    min_value=5;
    time_on=min_value;
    time_off=max_value;
    rate_of_change=2;
    direction=down;
    while(1)
    {
        PORTB = 0b00011111;
        delay_us(time_on);
        PORTB = 0b00000000;
        delay_us(time_off);

        if (direction==up)
        {
            time_on+=rate_of_change;
            time_off-=rate_of_change;
            if (time_on>max_value)
                direction=down;
        }
        else
        {
            time_on-=rate_of_change;
            time_off+=rate_of_change;
            if (time_on<=min_value)
                direction=up;
        }

    }


    while(1);                                   // Ending infinite loop

}