//	MCU : ATtiny13
//		hfuse:FBh	BOD 2.7V
//		lfuse:22h	0.6MHz

#include	<avr/io.h>
#include	<avr/interrupt.h>
#include	<avr/pgmspace.h>
#include	<avr/eeprom.h>
#include	<stdio.h>
#include	<stdlib.h>
#include	<string.h>
#include	<ctype.h>

#include	"RadioKitRDA5820.h"
#include 	"RDA5820.h"

#define		DEFAULT_FREQ	813

volatile uchar	WTimer;
volatile uchar	SwFlag;

// Timer 0 Interrupt
ISR(TIM0_COMPA_vect)
{
	if (WTimer)	--WTimer;
	uchar pb = ~PINB;
	if ( pb & (1<<SW_UP))	SwFlag |= SWON_UP;
	if ( pb & (1<<SW_DN))	SwFlag |= SWON_DN;
}

// Main Routine
int main(void)
{
	ushort	freq;
	PORTB = (1<<SW_UP)|(1<<SW_DN)|(1<<CE);
	DDRB = (1<<CE);
	MCUCR = (1<<SE);					// スリープ許可、アイドリングモード
	TCCR0A = (1<<WGM01);				// CTC
	TCCR0B = (1<<CS01)|(1<<CS00);		// プリスケーラ 1/64
	OCR0A = ((F_CPU/64 + 50)/100 - 1);	// 100Hz
	TIMSK0 = (1<<OCIE0A);				// 比較一致A割り込み許可
	ACSR |= (1<<ACD);					// アナログコンパレータ禁止
	sei();

	wait_timer(1000);

	// TWI リセット
	TWI_start();
	TWI_send(0xFF);
	TWI_start();
	TWI_stop();

	RDA5820_RX_Intialization();

	freq = eeprom_read_word(EEPROM_FREQ);
	if (freq == 0xFFFF)	freq = DEFAULT_FREQ;
	eeprom_write_word(EEPROM_FREQ, freq);

	set_freq(freq);
	wait_timer(100);
	set_Volume(10);
	PORTB &= ~(1<<CE);

	SwFlag = 0;
	for(;;){
		WDR;
		SLEEP;
		if ( SwFlag ) {
			if (SwFlag & SWON_UP ) {
				freq = seek(UP);				// Seek Up
			} else if ( SwFlag & SWON_DN ) {
				freq = seek(DOWN);				// Seek Down
			}
			wait_timer(100);
			eeprom_write_word(EEPROM_FREQ, freq);
			SwFlag = 0;
		}
	}
}

// 10ms wait
void wait_timer(uchar tm)
{
	WTimer = tm;
	while(WTimer){
		WDR;
		SLEEP;
	}
}

// Software TWI
void TWI_start(void)
{
	SDA_H;
	SCL_H;
	SDA_L;
	SCL_L;
}

void TWI_send(uchar data)
{
	char	bit;
	SCL_L;
	for (bit = 0; bit < 8; bit++)
	{
		if (data & 0x80)
		{
			SDA_H;
		} else {
			SDA_L;
		}
		SCL_H;
		WAIT_SCL_H;		// SCL=Hになるまで待つ
		data <<= 1;
		SCL_L;
	}
	SDA_H;
	SCL_L;
	// ACK受信 内容は無視
	SCL_H;
	SCL_L;
}

uchar TWI_recv(uchar nack)
{
	char	bit;
	uchar	data;
	SDA_H;
	SCL_L;
	data = 0;
	for (bit = 0; bit < 8; bit++)
	{
		SCL_H;
		WAIT_SCL_H;		// SCL=Hになるまで待つ
		data <<= 1;
		if (PINB & (1<<SDA))
		{
			data |= 1;
		}
		SCL_L;
	}

	// ACK/NACK 送信
	if (nack)
	{
		SCL_L;
		SCL_H;
		SDA_H;
	}
	else
	{
		SDA_L;
		SCL_L;
		SCL_H;
	}

	SCL_L;
	SDA_H;

	return data;
}

void TWI_stop(void)
{
	SCL_L;
	SDA_L;
	SCL_H;
	SDA_H;
}