contiki/examples/zolertia/zoul/test-dht22.c
2016-07-04 18:00:09 +02:00

89 lines
3.4 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-examples
* @{
*
* \defgroup zoul-dht22-test DHT22 temperature and humidity sensor test
*
* Demonstrates the use of the DHT22 digital temperature and humidity sensor
* @{
*
* \file
* A quick program for testing the DHT22 temperature and humidity sensor
* \author
* Antonio Lignan <alinan@zolertia.com>
*/
/*---------------------------------------------------------------------------*/
#include <stdio.h>
#include "contiki.h"
#include "dev/dht22.h"
/*---------------------------------------------------------------------------*/
PROCESS(remote_dht22_process, "DHT22 test");
AUTOSTART_PROCESSES(&remote_dht22_process);
/*---------------------------------------------------------------------------*/
static struct etimer et;
/*---------------------------------------------------------------------------*/
PROCESS_THREAD(remote_dht22_process, ev, data)
{
int16_t temperature, humidity;
PROCESS_BEGIN();
SENSORS_ACTIVATE(dht22);
/* Let it spin and read sensor data */
while(1) {
etimer_set(&et, CLOCK_SECOND);
PROCESS_WAIT_EVENT_UNTIL(etimer_expired(&et));
/* The standard sensor API may be used to read sensors individually, using
* the `dht22.value(DHT22_READ_TEMP)` and `dht22.value(DHT22_READ_HUM)`,
* however a single read operation (5ms) returns both values, so by using
* the function below we save one extra operation
*/
if(dht22_read_all(&temperature, &humidity) != DHT22_ERROR) {
printf("Temperature %02d.%02d ºC, ", temperature / 10, temperature % 10);
printf("Humidity %02d.%02d RH\n", humidity / 10, humidity % 10);
} else {
printf("Failed to read the sensor\n");
}
}
PROCESS_END();
}
/*---------------------------------------------------------------------------*/
/**
* @}
* @}
*/