nes-proj/examples/cc2530dk/sensors-demo.c
2012-12-16 19:28:56 +00:00

194 lines
6.2 KiB
C

/*
* Copyright (c) 2010, Loughborough University - Computer Science
* 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.
*/
/**
* \file
* Example to demonstrate-test cc2530 sensor functionality
*
* B1 turns LED_GREEN on and off.
*
* The node takes readings from the various sensors every x seconds and
* prints out the results.
*
* We use floats here to translate the AD conversion results to
* meaningful values. However, our printf does not have %f support so
* we use an ugly hack to print out the value by extracting the integral
* part and then the fractional part. Don't try this at home.
*
* Temperature:
* Math is correct, the sensor needs calibration per device.
* I currently use default values for the math which may result in
* very incorrect values in degrees C.
* See TI Design Note DN102 about the offset calibration.
*
* Supply Voltage (VDD):
* For VDD, math is correct, conversion is correct.
* See DN101 for details.
*
* Make sure you enable/disable things in contiki-conf.h
*
* \author
* George Oikonomou - <oikonomou@users.sourceforge.net>
*/
#include "contiki.h"
#include "contiki-conf.h"
#include "dev/leds.h"
#include "dev/button-sensor.h"
#include "dev/adc-sensor.h"
#define DEBUG 1
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#else /* DEBUG */
/* We overwrite (read as annihilate) all output functions here */
#define PRINTF(...)
#endif /* DEBUG */
/*---------------------------------------------------------------------------*/
PROCESS(sensors_test_process, "Sensor Test Process");
#if BUTTON_SENSOR_ON
PROCESS(buttons_test_process, "Button Test Process");
AUTOSTART_PROCESSES(&sensors_test_process, &buttons_test_process);
#else
AUTOSTART_PROCESSES(&sensors_test_process);
#endif
/*---------------------------------------------------------------------------*/
#if BUTTON_SENSOR_ON
PROCESS_THREAD(buttons_test_process, ev, data)
{
struct sensors_sensor *sensor;
PROCESS_BEGIN();
while(1) {
PROCESS_WAIT_EVENT_UNTIL(ev == sensors_event);
/* If we woke up after a sensor event, inform what happened */
sensor = (struct sensors_sensor *)data;
if(sensor == &button_sensor) {
PRINTF("Button Press\n");
leds_toggle(LEDS_GREEN);
}
}
PROCESS_END();
}
#endif
/*---------------------------------------------------------------------------*/
PROCESS_THREAD(sensors_test_process, ev, data)
{
static struct etimer et;
/* Sensor Values */
static int rv;
static struct sensors_sensor *sensor;
static float sane = 0;
static int dec;
static float frac;
PROCESS_BEGIN();
PRINTF("========================\n");
PRINTF("Starting Sensor Example.\n");
PRINTF("========================\n");
/* Set an etimer. We take sensor readings when it expires and reset it. */
etimer_set(&et, CLOCK_SECOND * 2);
while(1) {
PROCESS_WAIT_EVENT_UNTIL(etimer_expired(&et));
/*
* Request some ADC conversions
* Return value -1 means sensor not available or turned off in conf
*/
sensor = sensors_find(ADC_SENSOR);
if(sensor) {
PRINTF("------------------\n");
leds_on(LEDS_RED);
/*
* Temperature:
* Using 1.25V ref. voltage (1250mV).
* Typical AD Output at 25°C: 1480
* Typical Co-efficient : 4.5 mV/°C
*
* Thus, at 12bit decimation (and ignoring the VDD co-efficient as well
* as offsets due to lack of calibration):
*
* AD - 1480
* T = 25 + ---------
* 4.5
*/
rv = sensor->value(ADC_SENSOR_TYPE_TEMP);
if(rv != -1) {
sane = 25 + ((rv - 1480) / 4.5);
dec = sane;
frac = sane - dec;
PRINTF(" Temp=%d.%02u C (%d)\n", dec, (unsigned int)(frac*100), rv);
}
/*
* Power Supply Voltage.
* Using 1.25V ref. voltage.
* AD Conversion on VDD/3
*
* Thus, at 12bit resolution:
*
* ADC x 1.25 x 3
* Supply = -------------- V
* 2047
*/
rv = sensor->value(ADC_SENSOR_TYPE_VDD);
if(rv != -1) {
sane = rv * 3.75 / 2047;
dec = sane;
frac = sane - dec;
PRINTF("Supply=%d.%02u V (%d)\n", dec, (unsigned int)(frac*100), rv);
/* Store rv temporarily in dec so we can use it for the battery */
dec = rv;
}
/*
* Battery Voltage - ToDo
* rv = sensor->value(ADC_SENSOR_TYPE_BATTERY);
*/
leds_off(LEDS_RED);
}
etimer_reset(&et);
}
PROCESS_END();
}
/*---------------------------------------------------------------------------*/