// Copyright 2006 Yamane Akira
//ICC-AVR application builder : 2005/09
// Target : M48
// Crystal: 8.0000Mhz

#include <iom48v.h>
#include <macros.h>

unsigned char vl,vh,ch_bit;

void port_init(void)
{
 PORTB = 0xFF;
 DDRB  = 0xFF;
 PORTC = 0x00; 
 DDRC  = 0x00;
 PORTD = 0xFF;
 DDRD  = 0xFF;
}

//TIMER0 initialize - prescale:64
// WGM: CTC
// desired value: 500uSec
// actual value: 504.000uSec (-0.8%)
void timer0_init(void)
{
 TCCR0B = 0x00; //stop
 TCNT0 = 0xFF; //set count
 TCCR0A = 0x02; 
 OCR0A = 0x3E;
 TCCR0B = 0x03; //start timer
}

#pragma interrupt_handler timer0_compa_isr:15
void timer0_compa_isr(void)
{
  ch_bit = ch_bit ^ 0x01;
  ADMUX = 0x60 | ch_bit;
}
//ADC initialize
// Conversion time: 104uS
void adc_init(void)
{
 ADCSRA = 0x00; //disable adc
 ADMUX = 0x60;  //select adc input 0
 ACSR  = 0x80;
 ADCSRB = 0x03;
 DIDR0 = 0x03;
 ADCSRA = 0xAE;
}

#pragma interrupt_handler adc_isr:22
void adc_isr(void)
{
    vl=ADCL;            //Read 2 low bits first (important)
    vh=ADCH;            //Read 8 high bits
	 if (ch_bit == 0x00)
	     PORTD = ~vh;
		  else
		    PORTB = ~vh;
}

void init_devices(void)
{
 CLI(); //disable all interrupts
 port_init();
 timer0_init();
 adc_init();

 MCUCR = 0x00;
 EICRA = 0x00; //extended ext ints
 EIMSK = 0x00;
 
 TIMSK0 = 0x02; //timer 0 interrupt sources <---
 TIMSK1 = 0x00; //timer 1 interrupt sources
 TIMSK2 = 0x00; //timer 2 interrupt sources
 
 PCMSK0 = 0x00; //pin change mask 0 
 PCMSK1 = 0x00; //pin change mask 1 
 PCMSK2 = 0x00; //pin change mask 2
 PCICR = 0x00; //pin change enable 
 PRR = 0x00; //power controller
 SEI(); //re-enable interrupts
}

//
void main(void)
{
 init_devices();
   ch_bit = 0x01;
     while(1)
	  ;
}