contiki/platform/zoul/dev/dht22.h
2016-07-04 18:00:09 +02:00

115 lines
4.3 KiB
C

/*
* Copyright (c) 2016, Zolertia - http://www.zolertia.com
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This file is part of the Contiki operating system.
*
*/
/*---------------------------------------------------------------------------*/
/**
* \addtogroup zoul-sensors
* @{
*
* \defgroup zoul-dht22 DHT22 temperature and humidity sensor
*
* Driver for the DHT22 temperature and humidity sensor
* @{
*
* \file
* Header file for the DHT22 temperature and humidity sensor
*/
/*---------------------------------------------------------------------------*/
#include "lib/sensors.h"
/*---------------------------------------------------------------------------*/
#ifndef DHT22_H_
#define DHT22_H_
/* -------------------------------------------------------------------------- */
/**
* \name DHT22 default pin and port
* @{
*/
#ifdef DHT22_CONF_PIN
#define DHT22_PIN DHT22_CONF_PIN
#else
#define DHT22_PIN 5
#endif
#ifdef DHT22_CONF_PORT
#define DHT22_PORT DHT22_CONF_PORT
#else
#define DHT22_PORT GPIO_A_NUM
#endif
/** @} */
/* -------------------------------------------------------------------------- */
/**
* \name DHT22 available commands
* @{
*/
#define DHT22_READ_TEMP 0x01
#define DHT22_READ_HUM 0x02
#define DHT22_READ_ALL 0x03
/** @} */
/* -------------------------------------------------------------------------- */
/**
* \name DHT22 return types
* @{
*/
#define DHT22_ERROR (-1)
#define DHT22_SUCCESS 0x00
#define DHT22_BUSY 0xFF
/** @} */
/* -------------------------------------------------------------------------- */
/**
* \name DHT22 constants
* @{
*/
#define DHT22_BUFFER 5 /**< Buffer to store the samples */
#define DHT22_COUNT 8 /**< Minimum ticks to detect a "1" bit */
#define DHT22_MAX_TIMMING 85 /**< Maximum ticks in a single operation */
#define DHT22_READING_DELAY 1 /**< 1 us */
#define DHT22_READY_TIME 20 /**< 40 us */
#define DHT22_START_TIME (RTIMER_SECOND / 50) /**< 20 ms */
#define DHT22_AWAKE_TIME (RTIMER_SECOND / 4) /**< 250 ms */
/** @} */
/* -------------------------------------------------------------------------- */
/**
* \name DHT22 auxiliary functions
* @{
*/
int dht22_read_all(int *temperature, int *humidity);
/** @} */
/* -------------------------------------------------------------------------- */
#define DHT22_SENSOR "DHT22 sensor"
/* -------------------------------------------------------------------------- */
extern const struct sensors_sensor dht22;
/* -------------------------------------------------------------------------- */
#endif /* DHT22_H_ */
/* -------------------------------------------------------------------------- */
/**
* @}
* @}
*/