#include <avr/io.h>
#define F_CPU 16000000
#define BAUD 115200
#include <util/setbaud.h>
#include <util/delay.h>

int main(void) {
  /* setup for leads off detection: */
  PORTB |= (0 << PB3) | (0 << PB2);
  DDRB |= (0 << DDB3) | (0 << DDB2);
  /* initialize the serial communication */
  UBRR0 = UBRR_VALUE;
  UCSR0B = (1 << RXEN0) | (1 << TXEN0);
  UCSR0C = (3 << UCSZ00);
  /* initialize ADC: */
  PRR &= ~(1 << PRADC);
  DIDR0 = (1 << ADC0D);
  ADCSRA = (1 << ADEN) | (4 << ADPS0);

  while (1) {
    if ((PINB & (1 << PINB2)) || (PINB & (1 << PINB3)))
      Serial.println('!');
    else {
      ADCSRA |= (1 << ADSC);
      while ((ADCSRA & (1 << ADSC)));
      Serial.println(ADC);
    }

    _delay_ms(1);
  }
}