//this one dims and brightens the LED

//This is meant to run on an ATMEL ATMega328

//I think these are libraries to include
#include <avr/io.h>
#include <util/delay.h>

//these are functions you'll call later
#define output(directions,pin) (directions |= pin) // set port direction for output
#define input(directions,pin) (directions &= (~pin)) // set port direction for input
#define set(port,pin) (port |= pin) // set port pin
#define clear(port,pin) (port &= (~pin)) // clear port pin
#define pin_test(pins,pin) (pins & pin) // test for port pin
#define bit_test(byte,bit) (byte & (1 << bit)) // test for bit set

//these depend on how you set up the board
//inputs = buttons
#define button_port PORTC
#define button_direction DDRC //do I need this?
#define button1 (1 << PC0)
#define button2 (1 << PC1)
#define button3 (1 << PC2)
#define input_pins PINC //All my inputs are in C because I am just such a thoughtful circuit designer

//outputs = rgb led
#define led_port PORTB
#define led_direction DDRB
#define red (1 << PB0)
#define green (1 << PB1)
#define blue (1 << PB2)
#define led (green | red | blue) //it's all of them

//these are some helpful values you'll want later
#define led_delay() _delay_ms(100) // LED delay
#define PWM_delay() _delay_us(10) // PWM delay

int main (void){ //this is the main function - i.e. what runs all the time

// set clock divider to /1
// I don't entirely understand this, I just know it's in all the programs
CLKPR = (1 << CLKPCE);
CLKPR = (0 << CLKPS3) | (0 << CLKPS2) | (0 << CLKPS1) | (0 << CLKPS0);

//first initialize the buttons
clear(button_port, button1 | button2 | button3);
input(button_direction, button1 | button2 | button3);

//and initialize the LED
clear(led_port, red | green | blue); // | is bitwise operation, || is logical OR
output(led_direction, red | green | blue);
set(led_port, red | green | blue);


//now you want it listening for these buttons
//the buttons are connected to ground on one end, and to the IC on the other end
//so, you want the ports to listen for when they become ground, because it means the button is pressed

set(button_port, button1 | button2 | button3);

signed short int pwm_r, pwm_b, pwm_g,count,upper;//so it can hold more

upper=350; //this controls how long it takes to dim
pwm_r=upper;
pwm_g=upper;
pwm_b=upper;
//clear(led_port,led);//turn them all on
//_delay_ms(1000);
//set(led_port,led);
//_delay_ms(1000);

while (1){ //meaning, all the time



//in this case decrease the count when button is hit
//otherwise let it increase up to upper-1
  set(led_port,led); //turn them off
  for(count=1; count<upper; count=count+1){
    if(pwm_r==count){
      clear(led_port,red); //turn on if you hit that count
    }
    if(pwm_g==count){
      clear(led_port,green); //turn on if you hit that count
    }
    if(pwm_b==count){
      clear(led_port,blue); //turn on if you hit that count
    }
    PWM_delay();

   }//count to upper

    if(!pin_test(input_pins,button1)){
      pwm_r = 0;
    } else {
	if (pwm_r<upper){
      		pwm_r=pwm_r+1; //it increases time for it to get to
	}
    }

    if(!pin_test(input_pins,button2)){
      pwm_g = 0;
    } else {
	if (pwm_g<upper){
      		pwm_g=pwm_g+1; //it increases time for it to get to
	}
    }
    if(!pin_test(input_pins,button3)){
      pwm_b = 0;
    } else {
	if (pwm_b<upper){
      		pwm_b=pwm_b+1; //it increases time for it to get to
	}
    }



 } //while(1)


} //main