#include <avr/io.h>
#include <util/delay.h>
#include <avr/interrupt.h>

#include "rgbstring.h"

void init_serial()
{
	PORTB &= ~(_BV(PB2) | _BV(PB1));
	DDRB |= _BV(PB2) | _BV(PB1);

#if 0
	TCCR0A = _BV(WGM01) | _BV(WGM00);
	TCCR0B = _BV(WGM02) | _BV(CS00);
	OCR0A = 2;
#endif

	zero_frame();
}

static void send_byte(unsigned char b)
{
	unsigned char i, mask;

#if 0
	USIDR = b;
	USISR = _BV(USIOIF);
	USICR = _BV(USIWM0) | _BV(USICS0);

	while (!(USISR & _BV(USIOIF)))
		;
#endif

#if 1
	USIDR = b;
	USISR = _BV(USIOIF);

	while ( (USISR & _BV(USIOIF)) == 0 ) {
		USICR = _BV(USIWM0) | _BV(USICS1) | _BV(USICLK);
		USICR = _BV(USIWM0) | _BV(USICS1) | _BV(USICLK) | _BV(USITC);
	}
#endif

#if 0
	for (i = 0; i < 8; i++) {
		USICR = _BV(USIWM0) | _BV(USITC);
		USICR = _BV(USIWM0) | _BV(USITC) | _BV(USICLK);
	}
#endif

#if 0
	for (i = 0; i < 8; i++) {
		PORTB &= ~_BV(PB2);		// clock low
		if (b & 0x80)			// data bit on or off
			PORTB |= _BV(PB1);
		else
			PORTB &= ~_BV(PB1);
		b <<= 1;
		PORTB |= _BV(PB2);		// clock high
	}
#endif
}

void end_frame()
{
	PORTB &= ~_BV(PB2);			// clock low
	_delay_us(1000);
}

void send_rgb(unsigned char r, unsigned char g, unsigned char b)
{
	send_byte(r);
	send_byte(g);
	send_byte(b);
}


void zero_frame()
{
	unsigned char i;

	for (i = 0; i < STRIP_SIZE; i++) {
		send_rgb(0, 0, 0);
	}

	end_frame();
}