#define F_CPU 16000000UL

#include "../library/IC595.h"
#include "../library/LCD.h"

#include <util/delay.h>
#include <stdlib.h>
#include <string.h>

IC595 sr;
LCD lcd;

int pinSVR = 0;
int svr = 0;

void adc_init() {
  ADCSRA |= _BV(ADPS2) | _BV(ADPS1) | _BV(ADPS0);
  ADMUX = _BV(REFS0);
  ADCSRA |= _BV(ADEN);
  ADCSRA |= _BV(ADSC); 
}

uint16_t read_adc(uint8_t channel) {
  ADMUX &= 0xF0;
  ADMUX |= channel;
  ADCSRA |= _BV(ADSC);
  while (ADCSRA & _BV(ADSC));
  return ADCW;
}

ISR(TIMER1_OVF_vect) {
  svr = read_adc(0);
  OCR1A = 2000 + 2000*(svr/1024.0);
}

void timer_init() {
  TCCR1A = _BV(COM1A1) | _BV(WGM11);
  TCCR1B = _BV(CS11) | _BV(WGM13) | _BV(WGM12); // prescaler = 8
  
  TCNT1 = 0;
  ICR1 = 40000;
  OCR1A = 2000;
  
  TIMSK1 = _BV(TOIE1);

}

void setup() {
  IC595_init(&sr, 5, 6, 7);
  LCD_init(&lcd, &sr, 2, 3);
  
  // set analog
  adc_init();
  
  DDRB |= 0x02;
  cli();
  timer_init();
  sei();
}

int main() {
  setup();

  int i = 0;
  char str[5] = {0};

  //DDRB |= 0x04;
  //PORTB |= 0x04;

  while (1) {
    itoa(svr, str, 10);
    
    LCD_write_command( &lcd, (1<<7) | 0x00 );

    for (i=0; i<4; i++) {
      if (i < strlen(str))
        LCD_putch( &lcd, str[i] );
      else
        LCD_putch( &lcd, ' ' );
    }
    
    _delay_ms(10);
  }
  
  return 0;
}