//ICC-AVR application builder : 12/10/04 2:14:46 PM
// Target : 2313
// Crystal: 10.000Mhz

#include <io2313v.h>
#include <macros.h>
#define TRUE 1
#define FALSE 0
#define DELAY_LONG 25000
#define DELAY_SHORT 250
#define DELAY_MICRO 3
#define CLIP_SIZE 10

int ammo = 0, shot_delay = FALSE, clip = 0, cliptest = 0, pulse_cnt = 0, pulse_mode = FALSE, refresh = TRUE;

void pulse_start(); //calls pulse_end when it's done
void pulse_end();


void port_init(void)
{
 PORTB = 0x00;
 DDRB  = 0xFF; 
 PORTD = 0x0b00000111;
 DDRD  = 0x0b00000010; 
}

//TIMER0 initialize - prescale:8
// desired value: 73KHz
// actual value: 73.529KHz (0.7%)
void timer0_init(void)
{
 TCCR0 = 0x00; //stop timer
 TCNT0 = 0xEF; //set count
}

#pragma interrupt_handler timer0_ovf_isr:7
void timer0_ovf_isr(void)
{
 //TIMER0 has overflowed
 pulse_cnt++;
 if (pulse_cnt == 4000) {
 	TCCR0 = 0x00; //stop timer
 	pulse_end();
 }
 PORTB ^= BIT(0);
 TCNT0 = 0xEF; //reload counter value
}

//call this routine to initialize all peripherals
void init_devices(void)
{
 //stop errant interrupts until set up
 CLI(); //disable all interrupts
 port_init();
 timer0_init();

 MCUCR = 0x00;
 GIMSK = 0x00;
 TIMSK = 0x02;
 SEI(); //re-enable interrupts
 //all peripherals are now initialized
}
void delay(int delay_type, int length);
void play(int pitch, int length);
void play_reload();
void play_shot();

void main() {
	 init_devices();
	  
	 while (1) {
	 	    
	 	   if (pulse_mode == FALSE) {
	 	   
		   	  if (PIND & BIT(0)) shot_delay = FALSE;
	 
	 	   	  if (!(PIND & BIT(0)) && shot_delay == FALSE && ammo > 0) //if D0 is low
			  	 pulse_start();
				 
			  if (clip != 1 && cliptest != 1) {
			  	 cliptest = 1;
				 DDRD &= ~BIT(1);		//make D1 input
				 DDRD |= BIT(2);		//make D2 output
				 PORTD |= BIT(1);		//pull 1up = 1
				 PORTD &= ~BIT(2);		//out = 0
			  }
			  
			  if (clip != 1 && !(PIND & BIT(1))) { //load clip 1
			   	 clip = 1;
				 ammo = CLIP_SIZE;
				 refresh = TRUE;
				 play_reload();
			  }
			  
			  if (clip != 2 && cliptest != 2) {
			  	 cliptest = 2;
				 DDRD &= ~BIT(2);		//make D2 input
				 DDRD |= BIT(1);		//make D1 output
				 PORTD |= BIT(2);		//pull 2 up = 1
				 PORTD &= ~BIT(1);		//out = 0
			  }
			  
			  if (clip != 2 && !(PIND & BIT(2))) { //load clip 2
			  	 clip = 2;
				 ammo = CLIP_SIZE;
				 refresh = TRUE;
				 play_reload();
			  }
			  
			  if (refresh == TRUE) {
			  	 refresh = FALSE;
				 if (ammo > 2) {
				 	PORTB &= ~BIT(5); //red off
					PORTB |= BIT(4); //green on
				 }
				 else if (ammo > 0) {
				 	PORTB |= 0b00110000; //red green on
				 }
				 else {
				 	PORTB &= ~BIT(4); //green off
					PORTB |= BIT(5); //red on
				 }
			  }
			 
	 	   }
	 
	 }
}

void pulse_start() {
	 shot_delay = TRUE;
	 ammo--;
	 refresh = TRUE;

	 //muzzle flash 1 on
	 PORTB |= BIT(1);
	 
	 //enable IR flashing
	 pulse_cnt = 0;
	 pulse_mode = TRUE;
	 TCCR0 = 0x02; //start timer
}

void pulse_end() {
	 //disable IR flashing
	 pulse_mode = FALSE;
	 
	 //sound and muzzle flash 1 off
	 play_shot();
	 PORTB &= ~BIT(1);
	 
	 //shots two and three
	 play(2,1);
	 PORTB ^= BIT(1);
	 play_shot();
	 PORTB ^= BIT(1);
}
	 
void delay(int delay_type, int length) {
 	 	 int i, j;
		 for (i=0; i<length; i++) {
	 	 for (j=0; j<delay_type; j++); }
} 
	
void play(int pitch, int length) { //pitch of 1 = rest
	 int l, p;
	 for (l=0; l<length; l++) { //length loop
	 	 for (p=0; p<pitch/2; p++) {
		 	 PORTB ^= BIT(2);
		 	 delay(DELAY_SHORT, 400/pitch);
		 }
	 }
	 PORTB &= ~BIT(2);
}

void play_reload() {
	 play (40, 5);
	 play (1, 1);
	 play (60, 5);
	 play (1, 30);
}

void play_shot() {
	 play(400, 4);
	 play(200, 2);
}