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f1d8ab09ca
bme680-driver-fork/bme680_calculations.c
nagarajan f1d8ab09ca BME680 driver release
2016-06-22 17:53:09 +05:30

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/*
****************************************************************************
* Copyright (C) 2015 Bosch Sensortec GmbH
*
* File : bme680_calculations.c
*
* Date : 2016/06/10
*
* Revision: 2.0.0
*
* Usage: Sensor Driver for BME680 sensor
*
****************************************************************************
* \Section Disclaimer
* License:
*
* 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 holder nor the names of the
* 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 COPYRIGHT HOLDER
* 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
*
* The information provided is believed to be accurate and reliable.
* The copyright holder assumes no responsibility
* for the consequences of use
* of such information nor for any infringement of patents or
* other rights of third parties which may result from its use.
* No license is granted by implication or otherwise under any patent or
* patent rights of the copyright holder.
**************************************************************************/
/*! \file bme680_calculations.c
\brief BME680 Sensor Driver calculation source File */
/***************************************************************************
Header files
****************************************************************************/
#include "bme680_calculations.h"
/***************************************************************************
Macros, Enums, Constants
****************************************************************************/
/***************************************************************************
File globals, typedefs
****************************************************************************/
/***************************************************************************
Function definitions
****************************************************************************/
/* bme680.c */
#ifdef FIXED_POINT_COMPENSATION
/*!
* @brief This function is used to convert uncompensated gas data to
* compensated gas data using compensation formula(integer version)
*
* @param gas_adc_u16: The value of gas resistance calculated
* using temperature
* @param gas_range_u8: The value of gas range form register value
* @param bme680: structure pointer.
*
* @return calculated compensated gas from compensation formula
* @retval compensated gas data
*
*
*/
s32 bme680_calculate_gas_int32(u16 gas_adc_u16, u8 gas_range_u8,
struct bme680_t *bme680)
{
s8 range_switching_error_val = BME680_INIT_VALUE;
s64 var1 = BME680_INIT_VALUE;
s64 var2 = BME680_INIT_VALUE;
s32 gas_res = BME680_INIT_VALUE;
const u64 lookup_k1_range[BME680_GAS_RANGE_RL_LENGTH] = {
2147483647UL, 2147483647UL, 2147483647UL, 2147483647UL, 2147483647UL,
2126008810UL, 2147483647UL, 2130303777UL, 2147483647UL, 2147483647UL,
2143188679UL, 2136746228UL, 2147483647UL, 2126008810UL, 2147483647UL,
2147483647UL};
const u64 lookup_k2_range[BME680_GAS_RANGE_RL_LENGTH] = {
4096000000UL, 2048000000UL, 1024000000UL, 512000000UL,
255744255UL, 127110228UL, 64000000UL, 32258064UL, 16016016UL,
8000000UL, 4000000UL, 2000000UL, 1000000UL, 500000UL, 250000UL,
125000UL};
range_switching_error_val =
bme680->cal_param.range_switching_error;
var1 = (s64)((1340 + (5 * (s64)range_switching_error_val)) *
((s64)lookup_k1_range[gas_range_u8])) >> 16;
var2 = (s64)((s64)gas_adc_u16 << 15) - (s64)(1 << 24) + var1;
#ifndef __KERNEL__
gas_res = (s32)(((((s64)lookup_k2_range[gas_range_u8] *
(s64)var1) >> 9) + (var2 >> 1)) / var2);
#else
gas_res = (s32)(div64_s64(((((s64)lookup_k2_range[gas_range_u8] *
(s64)var1) >> 9) + (var2 >> 1)), var2));
#endif
return gas_res;
}
/*!
* @brief This function is used to convert the uncompensated
* temperature data to compensated temperature data using
* compensation formula(integer version)
* @note Returns the value in 0.01 degree Centigrade
* Output value of "5123" equals 51.23 DegC.
*
*
*
* @param v_uncomp_temperature_u32 : value of uncompensated temperature
* @param bme680: structure pointer.
*
* @return Returns the compensated temperature data
*
*/
s32 bme680_compensate_temperature_int32(u32 v_uncomp_temperature_u32,
struct bme680_t *bme680)
{
s32 var1 = BME680_INIT_VALUE;
s32 var2 = BME680_INIT_VALUE;
s32 var3 = BME680_INIT_VALUE;
s32 temp_comp = BME680_INIT_VALUE;
var1 = ((s32)v_uncomp_temperature_u32 >> 3) -
((s32)bme680->cal_param.par_T1 << 1);
var2 = (var1 * (s32)bme680->cal_param.par_T2) >> 11;
var3 = ((((var1 >> 1) * (var1 >> 1)) >> 12) *
((s32)bme680->cal_param.par_T3 << 4)) >> 14;
bme680->cal_param.t_fine = var2 + var3;
temp_comp = ((bme680->cal_param.t_fine * 5) + 128) >> 8;
return temp_comp;
}
/*!
* @brief This function is used to convert the uncompensated
* humidity data to compensated humidity data using
* compensation formula(integer version)
*
* @note Returns the value in %rH as unsigned 32bit integer
* in Q22.10 format(22 integer 10 fractional bits).
* @note An output value of 42313
* represents 42313 / 1024 = 41.321 %rH
*
*
*
* @param v_uncomp_humidity_u32: value of uncompensated humidity
* @param bme680: structure pointer.
*
* @return Return the compensated humidity data
*
*/
s32 bme680_compensate_humidity_int32(u32 v_uncomp_humidity_u32,
struct bme680_t *bme680)
{
s32 temp_scaled = BME680_INIT_VALUE;
s32 var1 = BME680_INIT_VALUE;
s32 var2 = BME680_INIT_VALUE;
s32 var3 = BME680_INIT_VALUE;
s32 var4 = BME680_INIT_VALUE;
s32 var5 = BME680_INIT_VALUE;
s32 var6 = BME680_INIT_VALUE;
s32 humidity_comp = BME680_INIT_VALUE;
temp_scaled = (((s32)bme680->cal_param.t_fine * 5) + 128) >> 8;
var1 = (s32)v_uncomp_humidity_u32 -
((s32)((s32)bme680->cal_param.par_H1 << 4)) -
(((temp_scaled * (s32)bme680->cal_param.par_H3) /
((s32)100)) >> 1);
var2 = ((s32)bme680->cal_param.par_H2 *
(((temp_scaled * (s32)bme680->cal_param.par_H4) /
((s32)100)) + (((temp_scaled *
((temp_scaled * (s32)bme680->cal_param.par_H5) /
((s32)100))) >> 6) / ((s32)100)) + (s32)(1 << 14))) >> 10;
var3 = var1 * var2;
var4 = ((((s32)bme680->cal_param.par_H6) << 7) +
((temp_scaled * (s32)bme680->cal_param.par_H7) /
((s32)100))) >> 4;
var5 = ((var3 >> 14) * (var3 >> 14)) >> 10;
var6 = (var4 * var5) >> 1;
humidity_comp = (var3 + var6) >> 12;
if (humidity_comp > BME680_MAX_HUMIDITY_VALUE)
humidity_comp = BME680_MAX_HUMIDITY_VALUE;
else if (humidity_comp < BME680_MIN_HUMIDITY_VALUE)
humidity_comp = BME680_MIN_HUMIDITY_VALUE;
return humidity_comp;
}
/*!
* @brief This function is used to convert the uncompensated
* pressure data to compensated pressure data data using
* compensation formula(integer version)
*
* @note Returns the value in Pascal(Pa)
* Output value of "96386" equals 96386 Pa =
* 963.86 hPa = 963.86 millibar
*
*
*
* @param v_uncomp_pressure_u32 : value of uncompensated pressure
* @param bme680: structure pointer.
*
* @return Return the compensated pressure data
*
*/
s32 bme680_compensate_pressure_int32(u32 v_uncomp_pressure_u32,
struct bme680_t *bme680)
{
s32 var1 = BME680_INIT_VALUE;
s32 var2 = BME680_INIT_VALUE;
s32 var3 = BME680_INIT_VALUE;
s32 var4 = BME680_INIT_VALUE;
s32 pressure_comp = BME680_INIT_VALUE;
var1 = (((s32)bme680->cal_param.t_fine) >> 1) - 64000;
var2 = ((((var1 >> 2) * (var1 >> 2)) >> 11) *
(s32)bme680->cal_param.par_P6) >> 2;
var2 = var2 + ((var1 * (s32)bme680->cal_param.par_P5) << 1);
var2 = (var2 >> 2) + ((s32)bme680->cal_param.par_P4 << 16);
var1 = (((((var1 >> 2) * (var1 >> 2)) >> 13) *
((s32)bme680->cal_param.par_P3 << 5)) >> 3) +
(((s32)bme680->cal_param.par_P2 * var1) >> 1);
var1 = var1 >> 18;
var1 = ((32768 + var1) * (s32)bme680->cal_param.par_P1) >> 15;
pressure_comp = 1048576 - v_uncomp_pressure_u32;
pressure_comp = (s32)((pressure_comp - (var2 >> 12)) * ((u32)3125));
var4 = (1 << 31);
if (pressure_comp >= var4)
pressure_comp = ((pressure_comp / (u32)var1) << 1);
else
pressure_comp = ((pressure_comp << 1) / (u32)var1);
var1 = ((s32)bme680->cal_param.par_P9 * (s32)(((pressure_comp >> 3) *
(pressure_comp >> 3)) >> 13)) >> 12;
var2 = ((s32)(pressure_comp >> 2) *
(s32)bme680->cal_param.par_P8) >> 13;
var3 = ((s32)(pressure_comp >> 8) * (s32)(pressure_comp >> 8) *
(s32)(pressure_comp >> 8) *
(s32)bme680->cal_param.par_P10) >> 17;
pressure_comp = (s32)(pressure_comp) + ((var1 + var2 + var3 +
((s32)bme680->cal_param.par_P7 << 7)) >> 4);
return pressure_comp;
}
/*!
* @brief This function is used to convert temperature to resistance
* using the integer compensation formula
*
* @param heater_temp_u16: The value of heater temperature
* @param ambient_temp_s16: The value of ambient temperature
* @param bme680: structure pointer.
*
* @return calculated resistance from temperature
*
*
*
*/
u8 bme680_convert_temperature_to_resistance_int32(u16 heater_temp_u16,
s16 ambient_temp_s16, struct bme680_t *bme680)
{
s32 var1 = BME680_INIT_VALUE;
s32 var2 = BME680_INIT_VALUE;
s32 var3 = BME680_INIT_VALUE;
s32 var4 = BME680_INIT_VALUE;
s32 var5 = BME680_INIT_VALUE;
s32 res_heat_x100 = BME680_INIT_VALUE;
u8 res_heat = BME680_INIT_VALUE;
if ((heater_temp_u16 >= BME680_GAS_PROFILE_TEMPERATURE_MIN)
&& (heater_temp_u16 <= BME680_GAS_PROFILE_TEMPERATURE_MAX)) {
var1 = (((s32)ambient_temp_s16 *
bme680->cal_param.par_GH3) / 10) << 8;
var2 = (bme680->cal_param.par_GH1 + 784) *
(((((bme680->cal_param.par_GH2 + 154009) *
heater_temp_u16 * 5) / 100) + 3276800) / 10);
var3 = var1 + (var2 >> 1);
var4 = (var3 / (bme680->cal_param.res_heat_range + 4));
var5 = (131 * bme680->cal_param.res_heat_val) + 65536;
res_heat_x100 = (s32)(((var4 / var5) - 250) * 34);
res_heat = (u8) ((res_heat_x100 + 50) / 100);
}
return res_heat;
}
/*!
* @brief Reads actual humidity from uncompensated humidity
* @note Returns the value in %rH as unsigned 16bit integer
* @note An output value of 42313
* represents 42313/512 = 82.643 %rH
*
*
*
* @param v_uncomp_humidity_u32: value of uncompensated humidity
* @param bme680: structure pointer.
*
* @return Return the actual relative humidity output as u16
*
*/
u16 bme680_compensate_H_int32_sixteen_bit_output(u32 v_uncomp_humidity_u32,
struct bme680_t *bme680)
{
u32 v_x1_u32 = BME680_INIT_VALUE;
u16 v_x2_u32 = BME680_INIT_VALUE;
v_x1_u32 = (u32) bme680_compensate_humidity_int32(
v_uncomp_humidity_u32, bme680);
v_x2_u32 = (u16)(v_x1_u32 >> 1);
return v_x2_u32;
}
/*!
* @brief Reads actual temperature from uncompensated temperature
* @note Returns the value with 500LSB/DegC centred around 24 DegC
* output value of "5123" equals(5123/500)+24 = 34.246DegC
*
*
* @param v_uncomp_temperature_u32: value of uncompensated temperature
* @param bme680: structure pointer.
*
*
* @return Return the actual temperature as s16 output
*
*/
s16 bme680_compensate_T_int32_sixteen_bit_output(u32 v_uncomp_temperature_u32,
struct bme680_t *bme680)
{
s16 temperature = BME680_INIT_VALUE;
bme680_compensate_temperature_int32(v_uncomp_temperature_u32, bme680);
temperature = (s16)((((
bme680->cal_param.t_fine - 122880) * 25) + 128) >> 8);
return temperature;
}
/*!
* @brief Reads actual pressure from uncompensated pressure
* @note Returns the value in Pa.
* @note Output value of "12337434"
* @note represents 12337434 / 128 = 96386.2 Pa = 963.862 hPa
*
*
*
* @param v_uncomp_pressure_u32 : value of uncompensated pressure
* @param bme680: structure pointer.
*
* @return the actual pressure in u32
*
*/
u32 bme680_compensate_P_int32_twentyfour_bit_output(u32 v_uncomp_pressure_u32,
struct bme680_t *bme680)
{
u32 pressure = BME680_INIT_VALUE;
pressure = (u32)bme680_compensate_pressure_int32(
v_uncomp_pressure_u32, bme680);
pressure = (u32)(pressure >> 1);
return pressure;
}
#else
/*!
* @brief This function is used to convert uncompensated gas data to
* compensated gas data using compensation formula
*
* @param gas_adc_u16: The value of gas resistance calculated
* using temperature
* @param gas_range_u8: The value of gas range form register value
* @param bme680: structure pointer.
*
* @return calculated compensated gas from compensation formula
* @retval compensated gas
*
*
*/
double bme680_compensate_gas_double(u16 gas_adc_u16, u8 gas_range_u8,
struct bme680_t *bme680)
{
double gas_res_d = BME680_INIT_VALUE;
#ifdef HEATER_C1_ENABLE
const double lookup_k1_range[BME680_GAS_RANGE_RL_LENGTH] = {
0.0, 0.0, 0.0, 0.0, 0.0, -1.0, 0.0, -0.8,
0.0, 0.0, -0.2, -0.5, 0.0, -1.0, 0.0, 0.0};
const double lookup_k2_range[BME680_GAS_RANGE_RL_LENGTH] = {
0.0, 0.0, 0.0, 0.0, 0.1, 0.7, 0.0, -0.8,
-0.1, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0};
s8 range_switching_error_val = BME680_INIT_VALUE;
double var1 = BME680_INIT_VALUE;
double var2 = BME680_INIT_VALUE;
double var3 = BME680_INIT_VALUE;
range_switching_error_val =
bme680->cal_param.range_switching_error;
var1 = (1340.0 + (5.0 * range_switching_error_val));
var2 = (var1) * (1.0 + lookup_k1_range[gas_range_u8]/100.0);
var3 = 1.0 + (lookup_k2_range[gas_range_u8]/100.0);
gas_res_d = 1.0 / (double)(var3 * (0.000000125) *
(double)(1 << gas_range_u8)
* (((((double)gas_adc_u16) - 512.00)/var2) + 1.0));
#else
gas_res_d = 1.0 / ((0.000000125) * (double)(1 << gas_range_u8) *
((((double)(gas_adc_u16) - 512.00) / 1365.3333) + 1.0));
#endif
return gas_res_d;
}
/*!
* @brief This function is used to convert the uncompensated
* humidity data to compensated humidity data data using
* compensation formula
* @note returns the value in relative humidity (%rH)
* @note Output value of "42.12" equals 42.12 %rH
*
* @param uncom_humidity_u16 : value of uncompensated humidity
* @param comp_temperature : value of compensated temperature
* @param bme680: structure pointer.
*
*
* @return Return the compensated humidity data in floating point
*
*/
double bme680_compensate_humidity_double(u16 uncom_humidity_u16,
double comp_temperature, struct bme680_t *bme680)
{
double humidity_comp = BME680_INIT_VALUE;
double var1 = BME680_INIT_VALUE;
double var2 = BME680_INIT_VALUE;
double var3 = BME680_INIT_VALUE;
double var4 = BME680_INIT_VALUE;
var1 = (double)((double)uncom_humidity_u16) - (((double)
bme680->cal_param.par_H1 * 16.0) +
(((double)bme680->cal_param.par_H3 / 2.0)
* comp_temperature));
var2 = var1 * ((double)(
((double) bme680->cal_param.par_H2 / 262144.0)
*(1.0 + (((double)bme680->cal_param.par_H4 / 16384.0)
* comp_temperature) + (((double)bme680->cal_param.par_H5
/ 1048576.0) * comp_temperature
* comp_temperature))));
var3 = (double) bme680->cal_param.par_H6 / 16384.0;
var4 = (double) bme680->cal_param.par_H7 / 2097152.0;
humidity_comp = var2 +
((var3 + (var4 * comp_temperature)) * var2 * var2);
if (humidity_comp > BME680_MAX_HUMIDITY_VALUE)
humidity_comp = BME680_MAX_HUMIDITY_VALUE;
else if (humidity_comp < BME680_MIN_HUMIDITY_VALUE)
humidity_comp = BME680_MIN_HUMIDITY_VALUE;
return humidity_comp;
}
/*!
* @brief This function is used to convert the uncompensated
* pressure data to compensated data using compensation formula
* @note Returns pressure in Pa as double.
* @note Output value of "96386.2"
* equals 96386.2 Pa = 963.862 hPa.
*
*
* @param uncom_pressure_u32 : value of uncompensated pressure
* @param bme680: structure pointer.
*
* @return Return the compensated pressure data in floating point
*
*/
double bme680_compensate_pressure_double(u32 uncom_pressure_u32,
struct bme680_t *bme680)
{
double data1_d = BME680_INIT_VALUE;
double data2_d = BME680_INIT_VALUE;
double data3_d = BME680_INIT_VALUE;
double pressure_comp = BME680_INIT_VALUE;
data1_d = (((double)bme680->cal_param.t_fine / 2.0) - 64000.0);
data2_d = data1_d * data1_d * (((double)bme680->cal_param.par_P6) /
(131072.0));
data2_d = data2_d + (data1_d * ((double)bme680->cal_param.par_P5) *
2.0);
data2_d = (data2_d / 4.0) + (((double)bme680->cal_param.par_P4) *
65536.0);
data1_d = (((((double)bme680->cal_param.par_P3 * data1_d
* data1_d) / 16384.0) + ((double)bme680->cal_param.par_P2
* data1_d)) / 524288.0);
data1_d = ((1.0 + (data1_d / 32768.0)) *
((double)bme680->cal_param.par_P1));
pressure_comp = (1048576.0 - ((double)uncom_pressure_u32));
/* Avoid exception caused by division by zero */
if ((int)data1_d != BME680_INIT_VALUE) {
pressure_comp = (((pressure_comp - (data2_d
/ 4096.0)) * 6250.0) / data1_d);
data1_d = (((double)bme680->cal_param.par_P9) *
pressure_comp * pressure_comp) / 2147483648.0;
data2_d = pressure_comp * (((double)bme680->cal_param.par_P8)
/ 32768.0);
data3_d = ((pressure_comp / 256.0) * (pressure_comp / 256.0) *
(pressure_comp / 256.0) *
(bme680->cal_param.par_P10 / 131072.0));
pressure_comp = (pressure_comp + (data1_d + data2_d + data3_d +
((double)bme680->cal_param.par_P7 * 128.0)) / 16.0);
return pressure_comp;
} else {
return BME680_INIT_VALUE;
}
}
/*!
* @brief This function used to convert temperature data
* to uncompensated temperature data using compensation formula
* @note returns the value in Degree centigrade
* @note Output value of "51.23" equals 51.23 DegC.
*
* @param uncom_temperature_u32 : value of uncompensated temperature
* @param bme680: structure pointer.
*
* @return Return the actual temperature in floating point
*
*/
double bme680_compensate_temperature_double(u32 uncom_temperature_u32,
struct bme680_t *bme680)
{
double data1_d = BME680_INIT_VALUE;
double data2_d = BME680_INIT_VALUE;
double temperature = BME680_INIT_VALUE;
/* calculate x1 data */
data1_d = ((((double)uncom_temperature_u32 / 16384.0)
- ((double)bme680->cal_param.par_T1 / 1024.0))
* ((double)bme680->cal_param.par_T2));
/* calculate x2 data */
data2_d = (((((double)uncom_temperature_u32 / 131072.0) -
((double)bme680->cal_param.par_T1 / 8192.0)) *
(((double)uncom_temperature_u32 / 131072.0) -
((double)bme680->cal_param.par_T1 / 8192.0))) *
((double)bme680->cal_param.par_T3 * 16.0));
/* t fine value*/
bme680->cal_param.t_fine = (s32)(data1_d + data2_d);
/* compensated temperature data*/
temperature = ((data1_d + data2_d) /
5120.0);
return temperature;
}
/*!
* @brief This function is used to convert temperature to resistance
* using the compensation formula
*
* @param heater_temp_u16: The value of heater temperature
* @param ambient_temp_s16: The value of ambient temperature
* @param bme680: structure pointer.
*
* @return calculated resistance from temperature
*
*
*
*/
double bme680_convert_temperature_to_resistance_double(u16 heater_temp_u16,
s16 ambient_temp_s16, struct bme680_t *bme680)
{
double var1 = BME680_INIT_VALUE;
double var2 = BME680_INIT_VALUE;
double var3 = BME680_INIT_VALUE;
double var4 = BME680_INIT_VALUE;
double var5 = BME680_INIT_VALUE;
double res_heat = BME680_INIT_VALUE;
if ((heater_temp_u16 >= BME680_GAS_PROFILE_TEMPERATURE_MIN)
&& (heater_temp_u16 <= BME680_GAS_PROFILE_TEMPERATURE_MAX)) {
#ifdef HEATER_C1_ENABLE
var1 = (((double)bme680->cal_param.par_GH1 / (16.0)) + 49.0);
var2 = ((((double)bme680->cal_param.par_GH2
/(32768.0)) * (0.0005)) + 0.00235);
#endif
var3 = ((double)bme680->cal_param.par_GH3 / (1024.0));
var4 = (var1 * (1.0 + (var2 * (double)heater_temp_u16)));
var5 = (var4 + (var3 * (double)ambient_temp_s16));
#ifdef HEATER_C1_ENABLE
res_heat = (u8)(3.4 * ((var5 *
(4 / (4 + (double)bme680->cal_param.res_heat_range)) *
(1/(1 + ((double)bme680->cal_param.res_heat_val
* 0.002)))) - 25));
#else
res_heat = (((var5 * (4.0 /
(4.0 + (double)bme680->cal_param.res_heat_range)))
- 25.0) * 3.4);
#endif
}
return (u8)res_heat;
}
#endif
/* bme680.c */
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