249 lines
8.1 KiB
C
249 lines
8.1 KiB
C
/*
|
|
* Copyright (c) 2008 Swedish Institute of 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:
|
|
*
|
|
* * Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* * 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.
|
|
* * Neither the name of the copyright holders nor the names of
|
|
* contributors may be used to endorse or promote products derived
|
|
* from this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
|
|
*/
|
|
/**
|
|
* \file
|
|
*
|
|
* \brief
|
|
* Driver for the on board temperature sensor.
|
|
*
|
|
* \author
|
|
* Mike Vidales mavida404@gmail.com
|
|
*
|
|
*/
|
|
|
|
#include "key.h"
|
|
#include "temp.h"
|
|
#include "lcd.h"
|
|
|
|
/**
|
|
* \addtogroup lcd
|
|
* \{
|
|
*/
|
|
|
|
/** Type used together with find_temp() to find temperature */
|
|
typedef enum {
|
|
TEMP_ZERO_OFFSET_CELCIUS = -15,
|
|
TEMP_ZERO_OFFSET_FAHRENHEIT = 0
|
|
} temp_zero_offset_t;
|
|
|
|
#if defined( DOXYGEN )
|
|
static uint16_t temp_table_celcius[];
|
|
static uint16_t temp_table_fahrenheit[];
|
|
#else /* !DOXYGEN */
|
|
/** Celcius temperatures (ADC-value) from -15 to 60 degrees */
|
|
static const uint16_t temp_table_celcius[] PROGMEM = {
|
|
923,917,911,904,898,891,883,876,868,860,851,843,834,825,815,
|
|
806,796,786,775,765,754,743,732,720,709,697,685,673,661,649,
|
|
636,624,611,599,586,574,562,549,537,524,512,500,488,476,464,
|
|
452,440,429,418,406,396,385,374,364,354,344,334,324,315,306,
|
|
297,288,279,271,263,255,247,240,233,225,219,212,205,199,193,
|
|
187,
|
|
};
|
|
|
|
/** Fahrenheit temperatures (ADC-value) from 0 to 140 degrees */
|
|
static const uint16_t temp_table_fahrenheit[] PROGMEM = {
|
|
938, 935, 932, 929, 926, 923, 920, 916, 913, 909, 906, 902, 898,
|
|
894, 891, 887, 882, 878, 874, 870, 865, 861, 856, 851, 847, 842,
|
|
837, 832, 827, 822, 816, 811, 806, 800, 795, 789, 783, 778, 772,
|
|
766, 760, 754, 748, 742, 735, 729, 723, 716, 710, 703, 697, 690,
|
|
684, 677, 670, 663, 657, 650, 643, 636, 629, 622, 616, 609, 602,
|
|
595, 588, 581, 574, 567, 560, 553, 546, 539, 533, 526, 519, 512,
|
|
505, 498, 492, 485, 478, 472, 465, 459, 452, 446, 439, 433, 426,
|
|
420, 414, 408, 402, 396, 390, 384, 378, 372, 366, 360, 355, 349,
|
|
344, 338, 333, 327, 322, 317, 312, 307, 302, 297, 292, 287, 282,
|
|
277, 273, 268, 264, 259, 255, 251, 246, 242, 238, 234, 230, 226,
|
|
222, 219, 215, 211, 207, 204, 200, 197, 194, 190, 187,
|
|
};
|
|
#endif /* !DOXYGEN */
|
|
|
|
/** Flag indicating initialized or not */
|
|
bool temp_initialized = false;
|
|
|
|
/** \brief Find array index corresponding to input ADC value
|
|
*
|
|
* Returned array index is actual temperature + zero offset. To
|
|
* get actual temperature, the zero offset (\ref temp_zero_offset_t)
|
|
* has to be subtracted.
|
|
*
|
|
* \param[in] value Value to seracah for in table
|
|
* \param[in] array Pointer to array in which to look for ADC value
|
|
* \param[in] count Size of array
|
|
*
|
|
*
|
|
* \return EOF on error
|
|
*/
|
|
static int find_temp(int16_t value, const uint16_t* array, int count);
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* \brief This will initialize the digital IO and adc channel for temperture readings.
|
|
* Optionally enable adc channel 2 for measurement of EXT_SUPL_SIG.
|
|
*
|
|
* \retval 0 Place holder for returning status.
|
|
*/
|
|
int
|
|
temp_init(void)
|
|
{
|
|
/* Disable the Digital IO for the analog readings. */
|
|
DIDR0 |= (1 << ADC4D);
|
|
|
|
/* Temp sens power pin as output */
|
|
TEMP_DDR |= (1 << TEMP_BIT_PWR);
|
|
|
|
/* Power off temp sensor */
|
|
TEMP_PORT &= ~(1 << TEMP_BIT_PWR);
|
|
|
|
/* Temp sens input, no pullup */
|
|
TEMP_DDR &= ~(1 << TEMP_BIT_IN);
|
|
TEMP_PORT &= ~(1 << TEMP_BIT_IN);
|
|
|
|
#if MEASURE_ADC2
|
|
DIDR0 |= (1 << ADC2D);
|
|
TEMP_DDR &= ~(1 << 2);
|
|
TEMP_PORT &= ~(1 << 2);
|
|
#endif
|
|
|
|
temp_initialized = true;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* \brief This will disable temperature readings by reseting the initialed flag.
|
|
*/
|
|
void
|
|
temp_deinit(void)
|
|
{
|
|
temp_initialized = false;
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* \brief This will turn on the adc channel for reading the temp sensor.
|
|
*
|
|
* After the raw adc value is stored, it will be used to lookup a degree conversion
|
|
* based on the tables for F or C.
|
|
* Optionally, EXT_SUPL_SIG is also read on channel 2 and stored in the global
|
|
* ADC2_reading for subsequent transfer to the 1284p web server.
|
|
*
|
|
* \param unit Used to determine what unit needs to be appended with the value.
|
|
*
|
|
* \return EOF This is an uninitialized adc error.
|
|
* \retval temp The newly converted value in degrees F or C.
|
|
*/
|
|
#if MEASURE_ADC2
|
|
uint16_t ADC2_reading;
|
|
#endif
|
|
|
|
int16_t
|
|
temp_get(temp_unit_t unit)
|
|
{
|
|
int16_t res;
|
|
int16_t temp;
|
|
|
|
/* Return if temp sensor driver not initialized */
|
|
if (temp_initialized == false) {
|
|
return EOF;
|
|
}
|
|
|
|
/* Power up sensor */
|
|
TEMP_PORT |= (1 << TEMP_BIT_PWR);
|
|
|
|
/* Init ADC and measure */
|
|
adc_init(ADC_CHAN_ADC4, ADC_TRIG_FREE_RUN, ADC_REF_AVCC, ADC_PS_128);
|
|
adc_conversion_start();
|
|
while ((res = adc_result_get(ADC_ADJ_RIGHT)) == EOF ){
|
|
;
|
|
}
|
|
|
|
#if MEASURE_ADC2
|
|
/* Measure external voltage supply, routed to ADC2 through a 470K/100K divider*/
|
|
/* AVCC is 3.3 volts if using external supply, else Vbat which will be lower */
|
|
/* Convert result to millivolts assuming AVCC is 3.3 volts, on battery it will be lower! */
|
|
adc_init(ADC_CHAN_ADC2, ADC_TRIG_FREE_RUN, ADC_REF_AVCC, ADC_PS_128);
|
|
adc_conversion_start();
|
|
while ((ADC2_reading = adc_result_get(ADC_ADJ_RIGHT)) == EOF ){
|
|
;
|
|
}
|
|
ADC2_reading = (ADC2_reading*((470+100)*3300UL))/(100*1024UL);
|
|
#endif
|
|
|
|
adc_deinit();
|
|
/* Re-init the adc for buttons. */
|
|
key_init();
|
|
|
|
/* Power down sensor */
|
|
TEMP_PORT &= ~(1 << TEMP_BIT_PWR);
|
|
|
|
/* Get corresponding temperature from table */
|
|
if (unit == TEMP_UNIT_CELCIUS) {
|
|
temp = find_temp(res, temp_table_celcius, sizeof(temp_table_celcius)/sizeof(int)) + TEMP_ZERO_OFFSET_CELCIUS;
|
|
} else /*unit == TEMP_UNIT_FAHRENHEIT*/{
|
|
temp = find_temp(res, temp_table_fahrenheit, sizeof(temp_table_fahrenheit)/sizeof(int)) + TEMP_ZERO_OFFSET_FAHRENHEIT;
|
|
}
|
|
|
|
return temp;
|
|
}
|
|
|
|
/*---------------------------------------------------------------------------*/
|
|
|
|
/**
|
|
* \brief Find array index corresponding to input ADC value
|
|
*
|
|
* Returned array index is actual temperature + zero offset. To
|
|
* get actual temperature, the zero offset (\ref temp_zero_offset_t)
|
|
* has to be subtracted.
|
|
*
|
|
* \param[in] value Value to search for in table
|
|
* \param[in] array Pointer to array in which to look for ADC value
|
|
* \param[in] count Size of array
|
|
*
|
|
* \return EOF on error
|
|
*/
|
|
static int
|
|
find_temp(int16_t value, const uint16_t* array, int count)
|
|
{
|
|
int i = 0;
|
|
int table_val = 0;
|
|
do{
|
|
table_val = pgm_read_word(&array[i]);
|
|
if (table_val < value) {
|
|
return i;
|
|
}
|
|
} while(++i<count);
|
|
return EOF;
|
|
}
|
|
|
|
/** \} */
|