/* Soil Sensor Firmware
 * Light Measurement & LED Status Indication
 * Sensiplicity Systems
 * 
 *  Copyright 2015
 * 
 *  Department of Botany and Plant Pathology
 *  Center for Genome Research and Biocomputing
 *  Oregon State University
 *  Corvallis, OR 97331
 * 
 * This program is not free software; you can not redistribute it and/or
 * modify it at all.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. */
#include "light.h"
#include <util/atomic.h>
#include <stddef.h>

#ifndef BREV
#error "No board revision specified. Please provide -DBREV=2 or -DBREV=4 on the command line."
#endif

#if BREV != 2 && BREV != 4
#error "Incorect board revision specified. Please provide -DBREV=2 or -DBREV=4 on the command line."
#endif

static volatile enum led_state_t LedState, RequestedState;

#if BREV == 2
/* Set the led to a visible state. */
void set_led(enum led_state_t state){
	/* Turn the anode on. */
	PORTD |= _BV(PD4);
	
	/* Turn LED off, then selectively turn on the required bits. */
	PORTD |= _BV(PD3);
	PORTE |= _BV(PE0);

	switch (state){
		case(LED_OFF):
			break;
		case(LED_GREEN):
			PORTE &= ~_BV(PE0);
			break;
		case(LED_RED):
			PORTD &= ~_BV(PD3);
			break;
	}
}
#elif BREV == 4
/* Set the led to a visible state. */
void set_led(enum led_state_t state){
	init_led();
	
	/* Turn the anode on. */
	DDRD |= _BV(PD4);
	PORTD |= _BV(PD4);
	
	/* Make the photodiode high impedance. */
	DDRD &= ~_BV(PD3);
	
	DDRE |= _BV(PE0);
	if(state == LED_GREEN || state == LED_RED){
		PORTE &= ~_BV(PE0);
	} else {
		PORTE |= _BV(PE0);
	}
}
#endif
/* Setup pins for the LED. */
void init_led(void){
	DDRD |= _BV(PD4);
	DDRD |= _BV(PD3);
	DDRE |= _BV(PE0);
}