dht22.h

/* struct dht22 AVR Lirary
 *
 * Copyright (C) 2015 Sergey Denisov.
 * Written by Sergey Denisov aka LittleBuster (DenisovS21@gmail.com)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version 3
 * of the Licence, or (at your option) any later version.
 *
 * Original library written by Adafruit Industries. MIT license.
 */

#ifndef __DHT22_H__
#define __DHT22_H__

#include <stdint.h>
#include "myriota_user_api.h"
#include "myriota_hardware_api.h"

/*
 * Sensor's port
 */
#define DDR_DHT DDRB
#define PORT_DHT PORTB
#define PIN_DHT PINB

/**
 * For MicroSleep
 */
#define CLOCK_RATE 48000000 // Clock rate 48MHz
#define CYCLE_PER_US (CLOCK_RATE / 1000000)
#define CYCLES_PER_LOOP 3

struct dht22
{
    uint8_t data[6]; /* data from sensor store here */
    uint8_t pin;     /* DDR & PORT pin */
};

/**
 * Init dht sensor
 * @dht: sensor struct
 * @pin: PORT & DDR pin
 */
void dht_init(struct dht22 *dht, uint8_t pin);

/**
 * Reading temperature from sensor
 * @dht: sensor struct
 * @temp: out temperature pointer
 *
 * Returns 1 if succeful reading
 * Returns 0 if fail reading
 */
uint8_t dht_read_temp(struct dht22 *dht, float *temp);

/**
 * Reading humidity from sensor
 * @dht: sensor struct
 * @hum: out humidity pointer
 *
 * Returns 1 if succeful reading
 * Returns 0 if fail reading
 */
uint8_t dht_read_hum(struct dht22 *dht, float *hum);

/**
 * Reading temperature and humidity from sensor
 * @dht: sensor struct
 * @temp: out temperature pointer
 * @hum: out humidity pointer
 *
 * Returns 1 if succeful reading
 * Returns 0 if fail reading
 *
 * The fastest function for getting temperature + humidity.
 */
uint8_t dht_read_data(struct dht22 *dht, float *temp, float *hum);

#endif