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bme280.h
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bme280.h
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/** \mainpage
*
****************************************************************************
* Copyright (C) 2015 - 2016 Bosch Sensortec GmbH
*
* File : bme280.h
*
* Date : 2016/07/04
*
* Revision : 2.0.5(Pressure and Temperature compensation code revision is 1.1
* and Humidity compensation code revision is 1.0)
*
* Usage: Sensor Driver for BME280 sensor
*
****************************************************************************
*
* \section 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 bme280.h
\brief BME280 Sensor Driver Support Header File */
#ifndef __BME280_H__
#define __BME280_H__
/*!
* @brief The following definition uses for define the data types
*
* @note While porting the API please consider the following
* @note Please check the version of C standard
* @note Are you using Linux platform
*/
/*!
* @brief For the Linux platform support
* Please use the types.h for your data types definitions
*/
#ifdef __KERNEL__
#include <linux/types.h>
#include <linux/math64.h>
#define BME280_64BITSUPPORT_PRESENT
/* singed integer type*/
typedef int8_t s8;/**< used for signed 8bit */
typedef int16_t s16;/**< used for signed 16bit */
typedef int32_t s32;/**< used for signed 32bit */
typedef int64_t s64;/**< used for signed 64bit */
typedef u_int8_t u8;/**< used for unsigned 8bit */
typedef u_int16_t u16;/**< used for unsigned 16bit */
typedef u_int32_t u32;/**< used for unsigned 32bit */
typedef u_int64_t u64;/**< used for unsigned 64bit */
#else /* ! __KERNEL__ */
/**********************************************************
* These definition uses for define the C
* standard version data types
***********************************************************/
# if defined(__STDC_VERSION__)
/************************************************
* compiler is C11 C standard
************************************************/
#if (__STDC_VERSION__ == 201112L)
/************************************************/
#include <stdint.h>
/************************************************/
/*unsigned integer types*/
typedef uint8_t u8;/**< used for unsigned 8bit */
typedef uint16_t u16;/**< used for unsigned 16bit */
typedef uint32_t u32;/**< used for unsigned 32bit */
typedef uint64_t u64;/**< used for unsigned 64bit */
/*signed integer types*/
typedef int8_t s8;/**< used for signed 8bit */
typedef int16_t s16;/**< used for signed 16bit */
typedef int32_t s32;/**< used for signed 32bit */
typedef int64_t s64;/**< used for signed 64bit */
#define BME280_64BITSUPPORT_PRESENT
/************************************************
* compiler is C99 C standard
************************************************/
#elif (__STDC_VERSION__ == 199901L)
/* stdint.h is a C99 supported c library.
which is used to fixed the integer size*/
/************************************************/
#include <stdint.h>
/************************************************/
/*unsigned integer types*/
typedef uint8_t u8;/**< used for unsigned 8bit */
typedef uint16_t u16;/**< used for unsigned 16bit */
typedef uint32_t u32;/**< used for unsigned 32bit */
typedef uint64_t u64;/**< used for unsigned 64bit */
/*signed integer types*/
typedef int8_t s8;/**< used for signed 8bit */
typedef int16_t s16;/**< used for signed 16bit */
typedef int32_t s32;/**< used for signed 32bit */
typedef int64_t s64;/**< used for signed 64bit */
#define BME280_64BITSUPPORT_PRESENT
/************************************************
* compiler is C89 or other C standard
************************************************/
#else /* !defined(__STDC_VERSION__) */
/*!
* @brief By default it is defined as 32 bit machine configuration
* define your data types based on your
* machine/compiler/controller configuration
*/
#define MACHINE_32_BIT
/*! @brief
* If your machine support 16 bit
* define the MACHINE_16_BIT
*/
#ifdef MACHINE_16_BIT
#include <limits.h>
/*signed integer types*/
typedef signed char s8;/**< used for signed 8bit */
typedef signed short int s16;/**< used for signed 16bit */
typedef signed long int s32;/**< used for signed 32bit */
#if defined(LONG_MAX) && LONG_MAX == 0x7fffffffffffffffL
typedef long int s64;/**< used for signed 64bit */
typedef unsigned long int u64;/**< used for unsigned 64bit */
#define BME280_64BITSUPPORT_PRESENT
#elif defined(LLONG_MAX) && (LLONG_MAX == 0x7fffffffffffffffLL)
typedef long long int s64;/**< used for signed 64bit */
typedef unsigned long long int u64;/**< used for unsigned 64bit */
#define BME280_64BITSUPPORT_PRESENT
#else
#warning Either the correct data type for signed 64 bit integer \
could not be found, or 64 bit integers are not supported in your environment.
#warning The API will only offer 32 bit pressure calculation.This will \
slightly impede accuracy(noise of ~1 pascal RMS will be added to output).
#warning If 64 bit integers are supported on your platform, \
please set s64 manually and "#define(BME280_64BITSUPPORT_PRESENT)" manually.
#endif
/*unsigned integer types*/
typedef unsigned char u8;/**< used for unsigned 8bit */
typedef unsigned short int u16;/**< used for unsigned 16bit */
typedef unsigned long int u32;/**< used for unsigned 32bit */
/* If your machine support 32 bit
define the MACHINE_32_BIT*/
#elif defined MACHINE_32_BIT
/*signed integer types*/
typedef signed char s8;/**< used for signed 8bit */
typedef signed short int s16;/**< used for signed 16bit */
typedef signed int s32;/**< used for signed 32bit */
typedef signed long long int s64;/**< used for signed 64bit */
/*unsigned integer types*/
typedef unsigned char u8;/**< used for unsigned 8bit */
typedef unsigned short int u16;/**< used for unsigned 16bit */
typedef unsigned int u32;/**< used for unsigned 32bit */
typedef unsigned long long int u64;/**< used for unsigned 64bit */
/*! @brief
* If your machine support 64 bit
* define the MACHINE_64_BIT
*/
#define BME280_64BITSUPPORT_PRESENT
/* If your machine support 64 bit
define the MACHINE_64_BIT*/
#elif defined MACHINE_64_BIT
/*signed integer types*/
typedef signed char s8;/**< used for signed 8bit */
typedef signed short int s16;/**< used for signed 16bit */
typedef signed int s32;/**< used for signed 32bit */
typedef signed long int s64;/**< used for signed 64bit */
/*unsigned integer types*/
typedef unsigned char u8;/**< used for unsigned 8bit */
typedef unsigned short int u16;/**< used for unsigned 16bit */
typedef unsigned int u32;/**< used for unsigned 32bit */
typedef unsigned long int u64;/**< used for unsigned 64bit */
#define BME280_64BITSUPPORT_PRESENT
#else
#warning The data types defined above which not supported \
define the data types manually
#endif
#endif
/*** This else will execute for the compilers
* which are not supported the C standards
* Like C89/C99/C11***/
#else
/*!
* @brief By default it is defined as 32 bit machine configuration
* define your data types based on your
* machine/compiler/controller configuration
*/
#define MACHINE_32_BIT
/* If your machine support 16 bit
define the MACHINE_16_BIT*/
#ifdef MACHINE_16_BIT
#include <limits.h>
/*signed integer types*/
typedef signed char s8;/**< used for signed 8bit */
typedef signed short int s16;/**< used for signed 16bit */
typedef signed long int s32;/**< used for signed 32bit */
#if defined(LONG_MAX) && LONG_MAX == 0x7fffffffffffffffL
typedef long int s64;/**< used for signed 64bit */
typedef unsigned long int u64;/**< used for unsigned 64bit */
#define BME280_64BITSUPPORT_PRESENT
#elif defined(LLONG_MAX) && (LLONG_MAX == 0x7fffffffffffffffLL)
typedef long long int s64;/**< used for signed 64bit */
typedef unsigned long long int u64;/**< used for unsigned 64bit */
#define BME280_64BITSUPPORT_PRESENT
#else
#warning Either the correct data type for signed 64 bit integer \
could not be found, or 64 bit integers are not supported in your environment.
#warning The API will only offer 32 bit pressure calculation.This will \
slightly impede accuracy(noise of ~1 pascal RMS will be added to output).
#warning If 64 bit integers are supported on your platform, \
please set s64 manually and "#define(BME280_64BITSUPPORT_PRESENT)" manually.
#endif
/*unsigned integer types*/
typedef unsigned char u8;/**< used for unsigned 8bit */
typedef unsigned short int u16;/**< used for unsigned 16bit */
typedef unsigned long int u32;/**< used for unsigned 32bit */
/*! @brief If your machine support 32 bit
define the MACHINE_32_BIT*/
#elif defined MACHINE_32_BIT
/*signed integer types*/
typedef signed char s8;/**< used for signed 8bit */
typedef signed short int s16;/**< used for signed 16bit */
typedef signed int s32;/**< used for signed 32bit */
typedef signed long long int s64;/**< used for signed 64bit */
/*unsigned integer types*/
typedef unsigned char u8;/**< used for unsigned 8bit */
typedef unsigned short int u16;/**< used for unsigned 16bit */
typedef unsigned int u32;/**< used for unsigned 32bit */
typedef unsigned long long int u64;/**< used for unsigned 64bit */
#define BME280_64BITSUPPORT_PRESENT
/* If your machine support 64 bit
define the MACHINE_64_BIT*/
#elif defined MACHINE_64_BIT
/*signed integer types*/
typedef signed char s8;/**< used for signed 8bit */
typedef signed short int s16;/**< used for signed 16bit */
typedef signed int s32;/**< used for signed 32bit */
typedef signed long int s64;/**< used for signed 64bit */
/*unsigned integer types*/
typedef unsigned char u8;/**< used for unsigned 8bit */
typedef unsigned short int u16;/**< used for unsigned 16bit */
typedef unsigned int u32;/**< used for unsigned 32bit */
typedef unsigned long int u64;/**< used for unsigned 64bit */
#define BME280_64BITSUPPORT_PRESENT
#else
#warning The data types defined above which not supported \
define the data types manually
#endif
#endif
#endif
/********************************************/
/**\name ENABLE FLOATING OUTPUT */
/**************************************/
/*!
* @brief If the user wants to support floating point calculations, please set
the following define. If floating point
calculation is not wanted or allowed
(e.g. in Linux kernel), please do not set the define. */
#define BME280_ENABLE_FLOAT
/*!
* @brief If the user wants to support 64 bit integer calculation
(needed for optimal pressure accuracy) please set
the following define. If int64 calculation is not wanted
(e.g. because it would include
large libraries), please do not set the define. */
#define BME280_ENABLE_INT64
/***************************************************************/
/**\name BUS READ AND WRITE FUNCTION POINTERS */
/***************************************************************/
/*!
@brief Define the calling convention of YOUR bus communication routine.
@note This includes types of parameters. This example shows the
configuration for an SPI bus link.
If your communication function looks like this:
write_my_bus_xy(u8 device_addr, u8 register_addr,
u8 * data, u8 length);
The BME280_WR_FUNC_PTR would equal:
BME280_WR_FUNC_PTR s8 (* bus_write)(u8,
u8, u8 *, u8)
Parameters can be mixed as needed refer to the
refer BME280_BUS_WRITE_FUNC macro.
*/
/** defines the return parameter type of the BME280_WR_FUNCTION */
#define BME280_BUS_WR_RETURN_TYPE s8
/* links the order of parameters defined in
BME280_BUS_WR_PARAM_TYPE to function calls used inside the API*/
#define BME280_BUS_WR_PARAM_TYPES u8, u8,\
u8 *, u8
/* links the order of parameters defined in
BME280_BUS_WR_PARAM_TYPE to function calls used inside the API*/
#define BME280_BUS_WR_PARAM_ORDER(device_addr, register_addr,\
register_data, wr_len)
/* never change this line */
#define BME280_BUS_WRITE_FUNC(device_addr, register_addr,\
register_data, wr_len) bus_write(device_addr, register_addr,\
register_data, wr_len)
/*!
@brief link macro between API function calls and bus read function
@note The bus write function can change since this is a
system dependant issue.
If the bus_read parameter calling order is like: reg_addr,
reg_data, wr_len it would be as it is here.
If the parameters are differently ordered or your communication
function like I2C need to know the device address,
you can change this macro accordingly.
BME280_BUS_READ_FUNC(dev_addr, reg_addr, reg_data, wr_len)\
bus_read(dev_addr, reg_addr, reg_data, wr_len)
This macro lets all API functions call YOUR communication routine in a
way that equals your definition in the
refer BME280_WR_FUNC_PTR definition.
@note: this macro also includes the "MSB='1'
for reading BME280 addresses.
*/
/*defines the return parameter type of the BME280_RD_FUNCTION
*/
#define BME280_BUS_RD_RETURN_TYPE s8
/**\brief defines the calling parameter types of the BME280_RD_FUNCTION
*/
#define BME280_BUS_RD_PARAM_TYPES (u8, u8,\
u8 *, u8)
/* links the order of parameters defined in \
BME280_BUS_RD_PARAM_TYPE to function calls used inside the API
*/
#define BME280_BUS_RD_PARAM_ORDER (device_addr, register_addr,\
register_data)
/* never change this line */
#define BME280_BUS_READ_FUNC(device_addr, register_addr,\
register_data, rd_len)bus_read(device_addr, register_addr,\
register_data, rd_len)
/****************************************/
/**\name DELAY */
/****************************************/
/* defines the return parameter type of the BME280_DELAY_FUNCTION
*/
#define BME280_DELAY_RETURN_TYPE void
/* defines the calling parameter types of the BME280_DELAY_FUNCTION
*/
#define BME280_DELAY_PARAM_TYPES u16
/***************************************************************/
/**\name GET AND SET BITSLICE FUNCTIONS */
/***************************************************************/
/* never change this line */
#define BME280_DELAY_FUNC(delay_in_msec)\
delay_func(delay_in_msec)
#define BME280_GET_BITSLICE(regvar, bitname)\
((regvar & bitname##__MSK) >> bitname##__POS)
#define BME280_SET_BITSLICE(regvar, bitname, val)\
((regvar & ~bitname##__MSK) | ((val<<bitname##__POS)&bitname##__MSK))
/***************************************************************/
/**\name COMMON USED CONSTANTS */
/***************************************************************/
/* Constants */
#define BME280_NULL (0)
#define BME280_RETURN_FUNCTION_TYPE s8
/* shift definitions*/
#define BME280_SHIFT_BIT_POSITION_BY_01_BIT (1)
#define BME280_SHIFT_BIT_POSITION_BY_02_BITS (2)
#define BME280_SHIFT_BIT_POSITION_BY_03_BITS (3)
#define BME280_SHIFT_BIT_POSITION_BY_04_BITS (4)
#define BME280_SHIFT_BIT_POSITION_BY_07_BITS (7)
#define BME280_SHIFT_BIT_POSITION_BY_08_BITS (8)
#define BME280_SHIFT_BIT_POSITION_BY_10_BITS (10)
#define BME280_SHIFT_BIT_POSITION_BY_11_BITS (11)
#define BME280_SHIFT_BIT_POSITION_BY_12_BITS (12)
#define BME280_SHIFT_BIT_POSITION_BY_13_BITS (13)
#define BME280_SHIFT_BIT_POSITION_BY_14_BITS (14)
#define BME280_SHIFT_BIT_POSITION_BY_15_BITS (15)
#define BME280_SHIFT_BIT_POSITION_BY_16_BITS (16)
#define BME280_SHIFT_BIT_POSITION_BY_17_BITS (17)
#define BME280_SHIFT_BIT_POSITION_BY_18_BITS (18)
#define BME280_SHIFT_BIT_POSITION_BY_19_BITS (19)
#define BME280_SHIFT_BIT_POSITION_BY_20_BITS (20)
#define BME280_SHIFT_BIT_POSITION_BY_25_BITS (25)
#define BME280_SHIFT_BIT_POSITION_BY_31_BITS (31)
#define BME280_SHIFT_BIT_POSITION_BY_33_BITS (33)
#define BME280_SHIFT_BIT_POSITION_BY_35_BITS (35)
#define BME280_SHIFT_BIT_POSITION_BY_47_BITS (47)
/* numeric definitions */
#define BME280_PRESSURE_TEMPERATURE_CALIB_DATA_LENGTH (26)
#define BME280_HUMIDITY_CALIB_DATA_LENGTH (7)
#define BME280_GEN_READ_WRITE_DATA_LENGTH (1)
#define BME280_HUMIDITY_DATA_LENGTH (2)
#define BME280_TEMPERATURE_DATA_LENGTH (3)
#define BME280_PRESSURE_DATA_LENGTH (3)
#define BME280_ALL_DATA_FRAME_LENGTH (8)
#define BME280_INIT_VALUE (0)
#define BME280_CHIP_ID_READ_COUNT (5)
#define BME280_INVALID_DATA (0)
/****************************************************/
/**\name ERROR CODE DEFINITIONS */
/***************************************************/
#define SUCCESS ((u8)0)
#define E_BME280_NULL_PTR ((s8)-127)
#define E_BME280_COMM_RES ((s8)-1)
#define E_BME280_OUT_OF_RANGE ((s8)-2)
#define ERROR ((s8)-1)
#define BME280_CHIP_ID_READ_FAIL ((s8)-1)
#define BME280_CHIP_ID_READ_SUCCESS ((u8)0)
/****************************************************/
/**\name CHIP ID DEFINITIONS */
/***************************************************/
#define BME280_CHIP_ID (0x60)
/****************************************************/
/**\name I2C ADDRESS DEFINITIONS */
/***************************************************/
#define BME280_I2C_ADDRESS1 (0x76)
#define BME280_I2C_ADDRESS2 (0x77)
/****************************************************/
/**\name POWER MODE DEFINITIONS */
/***************************************************/
/* Sensor Specific constants */
#define BME280_SLEEP_MODE (0x00)
#define BME280_FORCED_MODE (0x01)
#define BME280_NORMAL_MODE (0x03)
#define BME280_SOFT_RESET_CODE (0xB6)
/****************************************************/
/**\name STANDBY DEFINITIONS */
/***************************************************/
#define BME280_STANDBY_TIME_1_MS (0x00)
#define BME280_STANDBY_TIME_63_MS (0x01)
#define BME280_STANDBY_TIME_125_MS (0x02)
#define BME280_STANDBY_TIME_250_MS (0x03)
#define BME280_STANDBY_TIME_500_MS (0x04)
#define BME280_STANDBY_TIME_1000_MS (0x05)
#define BME280_STANDBY_TIME_10_MS (0x06)
#define BME280_STANDBY_TIME_20_MS (0x07)
/****************************************************/
/**\name OVER SAMPLING DEFINITIONS */
/***************************************************/
#define BME280_OVERSAMP_SKIPPED (0x00)
#define BME280_OVERSAMP_1X (0x01)
#define BME280_OVERSAMP_2X (0x02)
#define BME280_OVERSAMP_4X (0x03)
#define BME280_OVERSAMP_8X (0x04)
#define BME280_OVERSAMP_16X (0x05)
/****************************************************/
/**\name WORK MODE DEFINITIONS */
/***************************************************/
/*#define BME280_ULTRALOWPOWER_MODE (0x00)
#define BME280_LOWPOWER_MODE (0x01)
#define BME280_STANDARDRESOLUTION_MODE (0x02)
#define BME280_HIGHRESOLUTION_MODE (0x03)
#define BME280_ULTRAHIGHRESOLUTION_MODE (0x04)
#define BME280_ULTRALOWPOWER_OSRS_P BME280_OVERSAMP_1X
#define BME280_ULTRALOWPOWER_OSRS_T BME280_OVERSAMP_1X
#define BME280_LOWPOWER_OSRS_P BME280_OVERSAMP_2X
#define BME280_LOWPOWER_OSRS_T BME280_OVERSAMP_1X
#define BME280_STANDARDRESOLUTION_OSRS_P BME280_OVERSAMP_4X
#define BME280_STANDARDRESOLUTION_OSRS_T BME280_OVERSAMP_1X
#define BME280_HIGHRESOLUTION_OSRS_P BME280_OVERSAMP_8X
#define BME280_HIGHRESOLUTION_OSRS_T BME280_OVERSAMP_1X
#define BME280_ULTRAHIGHRESOLUTION_OSRS_P BME280_OVERSAMP_16X
#define BME280_ULTRAHIGHRESOLUTION_OSRS_T BME280_OVERSAMP_2X */
#define BME280_STANDARD_OVERSAMP_HUMIDITY BME280_OVERSAMP_1X
/****************************************************/
/**\name FILTER DEFINITIONS */
/***************************************************/
#define BME280_FILTER_COEFF_OFF (0x00)
#define BME280_FILTER_COEFF_2 (0x01)
#define BME280_FILTER_COEFF_4 (0x02)
#define BME280_FILTER_COEFF_8 (0x03)
#define BME280_FILTER_COEFF_16 (0x04)
/****************************************************/
/**\name DELAY DEFINITIONS */
/***************************************************/
#define T_INIT_MAX (20)
/* 20/16 = 1.25 ms */
#define T_MEASURE_PER_OSRS_MAX (37)
/* 37/16 = 2.3125 ms*/
#define T_SETUP_PRESSURE_MAX (10)
/* 10/16 = 0.625 ms */
#define T_SETUP_HUMIDITY_MAX (10)
/* 10/16 = 0.625 ms */
/****************************************************/
/**\name DEFINITIONS FOR ARRAY SIZE OF DATA */
/***************************************************/
#define BME280_HUMIDITY_DATA_SIZE (2)
#define BME280_TEMPERATURE_DATA_SIZE (3)
#define BME280_PRESSURE_DATA_SIZE (3)
#define BME280_DATA_FRAME_SIZE (8)
/**< data frames includes temperature,
pressure and humidity*/
#define BME280_CALIB_DATA_SIZE (26)
#define BME280_TEMPERATURE_MSB_DATA (0)
#define BME280_TEMPERATURE_LSB_DATA (1)
#define BME280_TEMPERATURE_XLSB_DATA (2)
#define BME280_PRESSURE_MSB_DATA (0)
#define BME280_PRESSURE_LSB_DATA (1)
#define BME280_PRESSURE_XLSB_DATA (2)
#define BME280_HUMIDITY_MSB_DATA (0)
#define BME280_HUMIDITY_LSB_DATA (1)
#define BME280_DATA_FRAME_PRESSURE_MSB_BYTE (0)
#define BME280_DATA_FRAME_PRESSURE_LSB_BYTE (1)
#define BME280_DATA_FRAME_PRESSURE_XLSB_BYTE (2)
#define BME280_DATA_FRAME_TEMPERATURE_MSB_BYTE (3)
#define BME280_DATA_FRAME_TEMPERATURE_LSB_BYTE (4)
#define BME280_DATA_FRAME_TEMPERATURE_XLSB_BYTE (5)
#define BME280_DATA_FRAME_HUMIDITY_MSB_BYTE (6)
#define BME280_DATA_FRAME_HUMIDITY_LSB_BYTE (7)
/****************************************************/
/**\name ARRAY PARAMETER FOR CALIBRATION */
/***************************************************/
#define BME280_TEMPERATURE_CALIB_DIG_T1_LSB (0)
#define BME280_TEMPERATURE_CALIB_DIG_T1_MSB (1)
#define BME280_TEMPERATURE_CALIB_DIG_T2_LSB (2)
#define BME280_TEMPERATURE_CALIB_DIG_T2_MSB (3)
#define BME280_TEMPERATURE_CALIB_DIG_T3_LSB (4)
#define BME280_TEMPERATURE_CALIB_DIG_T3_MSB (5)
#define BME280_PRESSURE_CALIB_DIG_P1_LSB (6)
#define BME280_PRESSURE_CALIB_DIG_P1_MSB (7)
#define BME280_PRESSURE_CALIB_DIG_P2_LSB (8)
#define BME280_PRESSURE_CALIB_DIG_P2_MSB (9)
#define BME280_PRESSURE_CALIB_DIG_P3_LSB (10)
#define BME280_PRESSURE_CALIB_DIG_P3_MSB (11)
#define BME280_PRESSURE_CALIB_DIG_P4_LSB (12)
#define BME280_PRESSURE_CALIB_DIG_P4_MSB (13)
#define BME280_PRESSURE_CALIB_DIG_P5_LSB (14)
#define BME280_PRESSURE_CALIB_DIG_P5_MSB (15)
#define BME280_PRESSURE_CALIB_DIG_P6_LSB (16)
#define BME280_PRESSURE_CALIB_DIG_P6_MSB (17)
#define BME280_PRESSURE_CALIB_DIG_P7_LSB (18)
#define BME280_PRESSURE_CALIB_DIG_P7_MSB (19)
#define BME280_PRESSURE_CALIB_DIG_P8_LSB (20)
#define BME280_PRESSURE_CALIB_DIG_P8_MSB (21)
#define BME280_PRESSURE_CALIB_DIG_P9_LSB (22)
#define BME280_PRESSURE_CALIB_DIG_P9_MSB (23)
#define BME280_HUMIDITY_CALIB_DIG_H1 (25)
#define BME280_HUMIDITY_CALIB_DIG_H2_LSB (0)
#define BME280_HUMIDITY_CALIB_DIG_H2_MSB (1)
#define BME280_HUMIDITY_CALIB_DIG_H3 (2)
#define BME280_HUMIDITY_CALIB_DIG_H4_MSB (3)
#define BME280_HUMIDITY_CALIB_DIG_H4_LSB (4)
#define BME280_HUMIDITY_CALIB_DIG_H5_MSB (5)
#define BME280_HUMIDITY_CALIB_DIG_H6 (6)
#define BME280_MASK_DIG_H4 (0x0F)
/****************************************************/
/**\name CALIBRATION REGISTER ADDRESS DEFINITIONS */
/***************************************************/
/*calibration parameters */
#define BME280_TEMPERATURE_CALIB_DIG_T1_LSB_REG (0x88)
#define BME280_TEMPERATURE_CALIB_DIG_T1_MSB_REG (0x89)
#define BME280_TEMPERATURE_CALIB_DIG_T2_LSB_REG (0x8A)
#define BME280_TEMPERATURE_CALIB_DIG_T2_MSB_REG (0x8B)
#define BME280_TEMPERATURE_CALIB_DIG_T3_LSB_REG (0x8C)
#define BME280_TEMPERATURE_CALIB_DIG_T3_MSB_REG (0x8D)
#define BME280_PRESSURE_CALIB_DIG_P1_LSB_REG (0x8E)
#define BME280_PRESSURE_CALIB_DIG_P1_MSB_REG (0x8F)
#define BME280_PRESSURE_CALIB_DIG_P2_LSB_REG (0x90)
#define BME280_PRESSURE_CALIB_DIG_P2_MSB_REG (0x91)
#define BME280_PRESSURE_CALIB_DIG_P3_LSB_REG (0x92)
#define BME280_PRESSURE_CALIB_DIG_P3_MSB_REG (0x93)
#define BME280_PRESSURE_CALIB_DIG_P4_LSB_REG (0x94)
#define BME280_PRESSURE_CALIB_DIG_P4_MSB_REG (0x95)
#define BME280_PRESSURE_CALIB_DIG_P5_LSB_REG (0x96)
#define BME280_PRESSURE_CALIB_DIG_P5_MSB_REG (0x97)
#define BME280_PRESSURE_CALIB_DIG_P6_LSB_REG (0x98)
#define BME280_PRESSURE_CALIB_DIG_P6_MSB_REG (0x99)
#define BME280_PRESSURE_CALIB_DIG_P7_LSB_REG (0x9A)
#define BME280_PRESSURE_CALIB_DIG_P7_MSB_REG (0x9B)
#define BME280_PRESSURE_CALIB_DIG_P8_LSB_REG (0x9C)
#define BME280_PRESSURE_CALIB_DIG_P8_MSB_REG (0x9D)
#define BME280_PRESSURE_CALIB_DIG_P9_LSB_REG (0x9E)
#define BME280_PRESSURE_CALIB_DIG_P9_MSB_REG (0x9F)
#define BME280_HUMIDITY_CALIB_DIG_H1_REG (0xA1)
#define BME280_HUMIDITY_CALIB_DIG_H2_LSB_REG (0xE1)
#define BME280_HUMIDITY_CALIB_DIG_H2_MSB_REG (0xE2)
#define BME280_HUMIDITY_CALIB_DIG_H3_REG (0xE3)
#define BME280_HUMIDITY_CALIB_DIG_H4_MSB_REG (0xE4)
#define BME280_HUMIDITY_CALIB_DIG_H4_LSB_REG (0xE5)
#define BME280_HUMIDITY_CALIB_DIG_H5_MSB_REG (0xE6)
#define BME280_HUMIDITY_CALIB_DIG_H6_REG (0xE7)
/****************************************************/
/**\name REGISTER ADDRESS DEFINITIONS */
/***************************************************/
#define BME280_CHIP_ID_REG (0xD0) /*Chip ID Register */
#define BME280_RST_REG (0xE0) /*Softreset Register */
#define BME280_STAT_REG (0xF3) /*Status Register */
#define BME280_CTRL_MEAS_REG (0xF4) /*Ctrl Measure Register */
#define BME280_CTRL_HUMIDITY_REG (0xF2) /*Ctrl Humidity Register*/
#define BME280_CONFIG_REG (0xF5) /*Configuration Register */
#define BME280_PRESSURE_MSB_REG (0xF7) /*Pressure MSB Register */
#define BME280_PRESSURE_LSB_REG (0xF8) /*Pressure LSB Register */
#define BME280_PRESSURE_XLSB_REG (0xF9) /*Pressure XLSB Register */
#define BME280_TEMPERATURE_MSB_REG (0xFA) /*Temperature MSB Reg */
#define BME280_TEMPERATURE_LSB_REG (0xFB) /*Temperature LSB Reg */
#define BME280_TEMPERATURE_XLSB_REG (0xFC) /*Temperature XLSB Reg */
#define BME280_HUMIDITY_MSB_REG (0xFD) /*Humidity MSB Reg */
#define BME280_HUMIDITY_LSB_REG (0xFE) /*Humidity LSB Reg */
/****************************************************/
/**\name BIT MASK, LENGTH AND POSITION DEFINITIONS */
/***************************************************/
/* Status Register */
#define BME280_STAT_REG_MEASURING__POS (3)
#define BME280_STAT_REG_MEASURING__MSK (0x08)
#define BME280_STAT_REG_MEASURING__LEN (1)
#define BME280_STAT_REG_MEASURING__REG (BME280_STAT_REG)
#define BME280_STAT_REG_IM_UPDATE__POS (0)
#define BME280_STAT_REG_IM_UPDATE__MSK (0x01)
#define BME280_STAT_REG_IM_UPDATE__LEN (1)
#define BME280_STAT_REG_IM_UPDATE__REG (BME280_STAT_REG)
/****************************************************/
/**\name BIT MASK, LENGTH AND POSITION DEFINITIONS
FOR TEMPERATURE OVERSAMPLING */
/***************************************************/
/* Control Measurement Register */
#define BME280_CTRL_MEAS_REG_OVERSAMP_TEMPERATURE__POS (5)
#define BME280_CTRL_MEAS_REG_OVERSAMP_TEMPERATURE__MSK (0xE0)
#define BME280_CTRL_MEAS_REG_OVERSAMP_TEMPERATURE__LEN (3)
#define BME280_CTRL_MEAS_REG_OVERSAMP_TEMPERATURE__REG \
(BME280_CTRL_MEAS_REG)
/****************************************************/
/**\name BIT MASK, LENGTH AND POSITION DEFINITIONS
FOR PRESSURE OVERSAMPLING */
/***************************************************/
#define BME280_CTRL_MEAS_REG_OVERSAMP_PRESSURE__POS (2)
#define BME280_CTRL_MEAS_REG_OVERSAMP_PRESSURE__MSK (0x1C)
#define BME280_CTRL_MEAS_REG_OVERSAMP_PRESSURE__LEN (3)
#define BME280_CTRL_MEAS_REG_OVERSAMP_PRESSURE__REG \
(BME280_CTRL_MEAS_REG)
/****************************************************/
/**\name BIT MASK, LENGTH AND POSITION DEFINITIONS
FOR POWER MODE */
/***************************************************/
#define BME280_CTRL_MEAS_REG_POWER_MODE__POS (0)
#define BME280_CTRL_MEAS_REG_POWER_MODE__MSK (0x03)
#define BME280_CTRL_MEAS_REG_POWER_MODE__LEN (2)
#define BME280_CTRL_MEAS_REG_POWER_MODE__REG \
(BME280_CTRL_MEAS_REG)
/****************************************************/
/**\name BIT MASK, LENGTH AND POSITION DEFINITIONS
FOR HUMIDITY OVERSAMPLING */
/***************************************************/
#define BME280_CTRL_HUMIDITY_REG_OVERSAMP_HUMIDITY__POS (0)
#define BME280_CTRL_HUMIDITY_REG_OVERSAMP_HUMIDITY__MSK (0x07)
#define BME280_CTRL_HUMIDITY_REG_OVERSAMP_HUMIDITY__LEN (3)
#define BME280_CTRL_HUMIDITY_REG_OVERSAMP_HUMIDITY__REG \
(BME280_CTRL_HUMIDITY_REG)
/****************************************************/
/**\name BIT MASK, LENGTH AND POSITION DEFINITIONS
FOR STANDBY TIME */
/***************************************************/
/* Configuration Register */
#define BME280_CONFIG_REG_TSB__POS (5)
#define BME280_CONFIG_REG_TSB__MSK (0xE0)
#define BME280_CONFIG_REG_TSB__LEN (3)
#define BME280_CONFIG_REG_TSB__REG (BME280_CONFIG_REG)
/****************************************************/
/**\name BIT MASK, LENGTH AND POSITION DEFINITIONS
FOR FILTER */
/***************************************************/
#define BME280_CONFIG_REG_FILTER__POS (2)
#define BME280_CONFIG_REG_FILTER__MSK (0x1C)
#define BME280_CONFIG_REG_FILTER__LEN (3)
#define BME280_CONFIG_REG_FILTER__REG (BME280_CONFIG_REG)
/****************************************************/
/**\name BIT MASK, LENGTH AND POSITION DEFINITIONS
FOR SPI ENABLE */
/***************************************************/
#define BME280_CONFIG_REG_SPI3_ENABLE__POS (0)
#define BME280_CONFIG_REG_SPI3_ENABLE__MSK (0x01)
#define BME280_CONFIG_REG_SPI3_ENABLE__LEN (1)
#define BME280_CONFIG_REG_SPI3_ENABLE__REG (BME280_CONFIG_REG)
/****************************************************/
/**\name BIT MASK, LENGTH AND POSITION DEFINITIONS
FOR PRESSURE AND TEMPERATURE DATA */
/***************************************************/
/* Data Register */
#define BME280_PRESSURE_XLSB_REG_DATA__POS (4)
#define BME280_PRESSURE_XLSB_REG_DATA__MSK (0xF0)
#define BME280_PRESSURE_XLSB_REG_DATA__LEN (4)
#define BME280_PRESSURE_XLSB_REG_DATA__REG (BME280_PRESSURE_XLSB_REG)
#define BME280_TEMPERATURE_XLSB_REG_DATA__POS (4)
#define BME280_TEMPERATURE_XLSB_REG_DATA__MSK (0xF0)
#define BME280_TEMPERATURE_XLSB_REG_DATA__LEN (4)
#define BME280_TEMPERATURE_XLSB_REG_DATA__REG (BME280_TEMPERATURE_XLSB_REG)
/****************************************************/
/**\name BUS READ AND WRITE FUNCTION POINTERS */
/***************************************************/
#define BME280_WR_FUNC_PTR\
s8 (*bus_write)(u8, u8,\
u8 *, u8)
#define BME280_RD_FUNC_PTR\
s8 (*bus_read)(u8, u8,\
u8 *, u8)
#define BME280_MDELAY_DATA_TYPE u32
#define BME280_3MS_DELAY (3)
#define BME280_REGISTER_READ_DELAY (1)
/**************************************************************/
/**\name STRUCTURE DEFINITIONS */
/**************************************************************/
/*!
* @brief This structure holds all device specific calibration parameters
*/
struct bme280_calibration_param_t {
u16 dig_T1;/**<calibration T1 data*/
s16 dig_T2;/**<calibration T2 data*/
s16 dig_T3;/**<calibration T3 data*/
u16 dig_P1;/**<calibration P1 data*/
s16 dig_P2;/**<calibration P2 data*/
s16 dig_P3;/**<calibration P3 data*/
s16 dig_P4;/**<calibration P4 data*/
s16 dig_P5;/**<calibration P5 data*/
s16 dig_P6;/**<calibration P6 data*/
s16 dig_P7;/**<calibration P7 data*/
s16 dig_P8;/**<calibration P8 data*/
s16 dig_P9;/**<calibration P9 data*/
u8 dig_H1;/**<calibration H1 data*/
s16 dig_H2;/**<calibration H2 data*/
u8 dig_H3;/**<calibration H3 data*/
s16 dig_H4;/**<calibration H4 data*/
s16 dig_H5;/**<calibration H5 data*/
s8 dig_H6;/**<calibration H6 data*/
s32 t_fine;/**<calibration T_FINE data*/
};
/*!
* @brief This structure holds BME280 initialization parameters
*/
struct bme280_t {
struct bme280_calibration_param_t cal_param;
/**< calibration parameters*/
u8 chip_id;/**< chip id of the sensor*/
u8 dev_addr;/**< device address of the sensor*/
u8 oversamp_temperature;/**< temperature over sampling*/
u8 oversamp_pressure;/**< pressure over sampling*/
u8 oversamp_humidity;/**< humidity over sampling*/
u8 ctrl_hum_reg;/**< status of control humidity register*/
u8 ctrl_meas_reg;/**< status of control measurement register*/
u8 config_reg;/**< status of configuration register*/
BME280_WR_FUNC_PTR;/**< bus write function pointer*/
BME280_RD_FUNC_PTR;/**< bus read function pointer*/
void (*delay_msec)(BME280_MDELAY_DATA_TYPE);/**< delay function pointer*/
};
/**************************************************************/
/**\name FUNCTION DECLARATIONS */
/**************************************************************/
/**************************************************************/
/**\name FUNCTION FOR INTIALIZATION */
/**************************************************************/
/*!
* @brief This function is used for initialize
* the bus read and bus write functions
* and assign the chip id and I2C address of the BME280 sensor
* chip id is read in the register 0xD0 bit from 0 to 7
*
* @param bme280 structure pointer.
*
* @note While changing the parameter of the bme280_t
* @note consider the following point:
* Changing the reference value of the parameter
* will changes the local copy or local reference
* make sure your changes will not
* affect the reference value of the parameter
* (Better case don't change the reference value of the parameter)
*
*
*
*
* @return results of bus communication function
* @retval 0 -> Success
* @retval -1 -> Error
*
*
*/
BME280_RETURN_FUNCTION_TYPE bme280_init(struct bme280_t *bme280);
/**************************************************************/
/**\name FUNCTION FOR INTIALIZATION UNCOMPENSATED TEMPERATURE */
/**************************************************************/
/*!
* @brief This API is used to read uncompensated temperature
* in the registers 0xFA, 0xFB and 0xFC
* @note 0xFA -> MSB -> bit from 0 to 7
* @note 0xFB -> LSB -> bit from 0 to 7
* @note 0xFC -> LSB -> bit from 4 to 7
*
* @param v_uncomp_temperature_s32 : The value of uncompensated temperature
*
*
*
* @return results of bus communication function
* @retval 0 -> Success
* @retval -1 -> Error
*
*
*/
BME280_RETURN_FUNCTION_TYPE bme280_read_uncomp_temperature(
s32 *v_uncomp_temperature_s32);
/**************************************************************/
/**\name FUNCTION FOR INTIALIZATION TRUE TEMPERATURE */
/**************************************************************/
/*!
* @brief Reads actual temperature from uncompensated temperature
* @note Returns the value in 0.01 degree Centigrade
* Output value of "5123" equals 51.23 DegC.
*
*
*
* @param v_uncomp_temperature_s32 : value of uncompensated temperature
*
*
* @return Returns the actual temperature
*
*/
s32 bme280_compensate_temperature_int32(s32 v_uncomp_temperature_s32);
/*!
* @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_s32: value of uncompensated temperature
*
*
*
* @return Return the actual temperature as s16 output
*
*/
s16 bme280_compensate_temperature_int32_sixteen_bit_output(
s32 v_uncomp_temperature_s32);
/**************************************************************/
/**\name FUNCTION FOR INTIALIZATION UNCOMPENSATED PRESSURE */
/**************************************************************/
/*!
* @brief This API is used to read uncompensated pressure.
* in the registers 0xF7, 0xF8 and 0xF9
* @note 0xF7 -> MSB -> bit from 0 to 7
* @note 0xF8 -> LSB -> bit from 0 to 7
* @note 0xF9 -> LSB -> bit from 4 to 7
*
*
*
* @param v_uncomp_pressure_s32 : The value of uncompensated pressure
*
*
*
* @return results of bus communication function
* @retval 0 -> Success
* @retval -1 -> Error
*
*
*/
BME280_RETURN_FUNCTION_TYPE bme280_read_uncomp_pressure(
s32 *v_uncomp_pressure_s32);
/**************************************************************/
/**\name FUNCTION FOR INTIALIZATION TRUE PRESSURE */
/**************************************************************/
/*!
* @brief Reads actual pressure from uncompensated pressure
* @note Returns the value in Pascal(Pa)
* Output value of "96386" equals 96386 Pa =
* 963.86 hPa = 963.86 millibar
*
*
*
* @param v_uncomp_pressure_s32 : value of uncompensated pressure
*
*
*
* @return Return the actual pressure output as u32
*
*/
u32 bme280_compensate_pressure_int32(s32 v_uncomp_pressure_s32);
/**************************************************************/
/**\name FUNCTION FOR INTIALIZATION UNCOMPENSATED HUMIDITY */
/**************************************************************/
/*!
* @brief This API is used to read uncompensated humidity.
* in the registers 0xF7, 0xF8 and 0xF9
* @note 0xFD -> MSB -> bit from 0 to 7
* @note 0xFE -> LSB -> bit from 0 to 7
*
*
*
* @param v_uncomp_humidity_s32 : The value of uncompensated humidity
*
*
*
* @return results of bus communication function
* @retval 0 -> Success
* @retval -1 -> Error
*
*
*/
BME280_RETURN_FUNCTION_TYPE bme280_read_uncomp_humidity(
s32 *v_uncomp_humidity_s32);
/**************************************************************/
/**\name FUNCTION FOR INTIALIZATION RELATIVE HUMIDITY */
/**************************************************************/
/*!
* @brief Reads actual humidity from uncompensated humidity