Diff: BME280.cpp

Revision:

2:853301624d95

Parent:

0:ac5ce2103c04

Child:

3:ab857b70346e

--- a/BME280.cpp	Tue Sep 03 15:00:49 2019 +0000
+++ b/BME280.cpp	Tue Sep 03 15:15:15 2019 +0000
@@ -0,0 +1,1367 @@
+/**
+ * @brief       BME280.cpp
+ * @details     Combined humidity and pressure sensor.
+ *              Function file.
+ *
+ *
+ * @return      N/A
+ *
+ * @author      Manuel Caballero
+ * @date        03/September/2019
+ * @version     03/September/2019    The ORIGIN
+ * @pre         This is just a port from Bosh driver to mBed ( c++ )
+ * @warning     N/A
+ * @pre         This code belongs to AqueronteBlog ( http://unbarquero.blogspot.com ).
+ */
+/**\mainpage
+* Copyright (C) 2018 - 2019 Bosch Sensortec GmbH
+*
+* 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.c
+* Date     08 Mar 2019
+* Version  3.3.6
+*
+*/
+
+/*! @file bme280.c
+ * @brief Sensor driver for BME280 sensor
+ */
+#include "BME280.h"
+
+BME280::BME280 ( PinName sda, PinName scl, uint32_t freq )
+    : _i2c          ( sda, scl )
+{
+    _i2c.frequency  ( freq );
+}
+
+
+BME280::~BME280()
+{
+}
+
+
+/**\name Internal macros */
+/* To identify osr settings selected by user */
+#define OVERSAMPLING_SETTINGS   UINT8_C(0x07)
+
+/* To identify filter and standby settings selected by user */
+#define FILTER_STANDBY_SETTINGS UINT8_C(0x18)
+
+/*!
+ * @brief This internal API puts the device to sleep mode.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ *
+ * @return Result of API execution status.
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+static int8_t put_device_to_sleep(const struct bme280_dev *dev);
+
+/*!
+ * @brief This internal API writes the power mode in the sensor.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[in] sensor_mode : Variable which contains the power mode to be set.
+ *
+ * @return Result of API execution status.
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+static int8_t write_power_mode(uint8_t sensor_mode, const struct bme280_dev *dev);
+
+/*!
+ * @brief This internal API is used to validate the device pointer for
+ * null conditions.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+static int8_t null_ptr_check(const struct bme280_dev *dev);
+
+/*!
+ * @brief This internal API interleaves the register address between the
+ * register data buffer for burst write operation.
+ *
+ * @param[in] reg_addr : Contains the register address array.
+ * @param[out] temp_buff : Contains the temporary buffer to store the
+ * register data and register address.
+ * @param[in] reg_data : Contains the register data to be written in the
+ * temporary buffer.
+ * @param[in] len : No of bytes of data to be written for burst write.
+ */
+static void interleave_reg_addr(const uint8_t *reg_addr, uint8_t *temp_buff, const uint8_t *reg_data, uint8_t len);
+
+/*!
+ * @brief This internal API reads the calibration data from the sensor, parse
+ * it and store in the device structure.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+static int8_t get_calib_data(struct bme280_dev *dev);
+
+/*!
+ *  @brief This internal API is used to parse the temperature and
+ *  pressure calibration data and store it in the device structure.
+ *
+ *  @param[out] dev : Structure instance of bme280_dev to store the calib data.
+ *  @param[in] reg_data : Contains the calibration data to be parsed.
+ */
+static void parse_temp_press_calib_data(const uint8_t *reg_data, struct bme280_dev *dev);
+
+/*!
+ *  @brief This internal API is used to parse the humidity calibration data
+ *  and store it in device structure.
+ *
+ *  @param[out] dev : Structure instance of bme280_dev to store the calib data.
+ *  @param[in] reg_data : Contains calibration data to be parsed.
+ */
+static void parse_humidity_calib_data(const uint8_t *reg_data, struct bme280_dev *dev);
+
+#ifdef BME280_FLOAT_ENABLE
+
+/*!
+ * @brief This internal API is used to compensate the raw pressure data and
+ * return the compensated pressure data in double data type.
+ *
+ * @param[in] uncomp_data : Contains the uncompensated pressure data.
+ * @param[in] calib_data : Pointer to the calibration data structure.
+ *
+ * @return Compensated pressure data.
+ * @retval Compensated pressure data in double.
+ */
+static double compensate_pressure(const struct bme280_uncomp_data *uncomp_data,
+                                  const struct bme280_calib_data *calib_data);
+
+/*!
+ * @brief This internal API is used to compensate the raw humidity data and
+ * return the compensated humidity data in double data type.
+ *
+ * @param[in] uncomp_data : Contains the uncompensated humidity data.
+ * @param[in] calib_data : Pointer to the calibration data structure.
+ *
+ * @return Compensated humidity data.
+ * @retval Compensated humidity data in double.
+ */
+static double compensate_humidity(const struct bme280_uncomp_data *uncomp_data,
+                                  const struct bme280_calib_data *calib_data);
+
+/*!
+ * @brief This internal API is used to compensate the raw temperature data and
+ * return the compensated temperature data in double data type.
+ *
+ * @param[in] uncomp_data : Contains the uncompensated temperature data.
+ * @param[in] calib_data : Pointer to calibration data structure.
+ *
+ * @return Compensated temperature data.
+ * @retval Compensated temperature data in double.
+ */
+static double compensate_temperature(const struct bme280_uncomp_data *uncomp_data,
+                                     struct bme280_calib_data *calib_data);
+
+#else
+
+/*!
+ * @brief This internal API is used to compensate the raw temperature data and
+ * return the compensated temperature data in integer data type.
+ *
+ * @param[in] uncomp_data : Contains the uncompensated temperature data.
+ * @param[in] calib_data : Pointer to calibration data structure.
+ *
+ * @return Compensated temperature data.
+ * @retval Compensated temperature data in integer.
+ */
+static int32_t compensate_temperature(const struct bme280_uncomp_data *uncomp_data,
+                                      struct bme280_calib_data *calib_data);
+
+/*!
+ * @brief This internal API is used to compensate the raw pressure data and
+ * return the compensated pressure data in integer data type.
+ *
+ * @param[in] uncomp_data : Contains the uncompensated pressure data.
+ * @param[in] calib_data : Pointer to the calibration data structure.
+ *
+ * @return Compensated pressure data.
+ * @retval Compensated pressure data in integer.
+ */
+static uint32_t compensate_pressure(const struct bme280_uncomp_data *uncomp_data,
+                                    const struct bme280_calib_data *calib_data);
+
+/*!
+ * @brief This internal API is used to compensate the raw humidity data and
+ * return the compensated humidity data in integer data type.
+ *
+ * @param[in] uncomp_data : Contains the uncompensated humidity data.
+ * @param[in] calib_data : Pointer to the calibration data structure.
+ *
+ * @return Compensated humidity data.
+ * @retval Compensated humidity data in integer.
+ */
+static uint32_t compensate_humidity(const struct bme280_uncomp_data *uncomp_data,
+                                    const struct bme280_calib_data *calib_data);
+
+#endif
+
+/*!
+ * @brief This internal API is used to identify the settings which the user
+ * wants to modify in the sensor.
+ *
+ * @param[in] sub_settings : Contains the settings subset to identify particular
+ * group of settings which the user is interested to change.
+ * @param[in] desired_settings : Contains the user specified settings.
+ *
+ * @return Indicates whether user is interested to modify the settings which
+ * are related to sub_settings.
+ * @retval True -> User wants to modify this group of settings
+ * @retval False -> User does not want to modify this group of settings
+ */
+static uint8_t are_settings_changed(uint8_t sub_settings, uint8_t desired_settings);
+
+/*!
+ * @brief This API sets the humidity oversampling settings of the sensor.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+static int8_t set_osr_humidity_settings(const struct bme280_settings *settings, const struct bme280_dev *dev);
+
+/*!
+ * @brief This internal API sets the oversampling settings for pressure,
+ * temperature and humidity in the sensor.
+ *
+ * @param[in] desired_settings : Variable used to select the settings which
+ * are to be set.
+ * @param[in] dev : Structure instance of bme280_dev.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+static int8_t set_osr_settings(uint8_t desired_settings,
+                               const struct bme280_settings *settings,
+                               const struct bme280_dev *dev);
+
+/*!
+ * @brief This API sets the pressure and/or temperature oversampling settings
+ * in the sensor according to the settings selected by the user.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[in] desired_settings: variable to select the pressure and/or
+ * temperature oversampling settings.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+static int8_t set_osr_press_temp_settings(uint8_t desired_settings,
+        const struct bme280_settings *settings,
+        const struct bme280_dev *dev);
+
+/*!
+ * @brief This internal API fills the pressure oversampling settings provided by
+ * the user in the data buffer so as to write in the sensor.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[out] reg_data : Variable which is filled according to the pressure
+ * oversampling data provided by the user.
+ */
+static void fill_osr_press_settings(uint8_t *reg_data, const struct bme280_settings *settings);
+
+/*!
+ * @brief This internal API fills the temperature oversampling settings provided
+ * by the user in the data buffer so as to write in the sensor.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[out] reg_data : Variable which is filled according to the temperature
+ * oversampling data provided by the user.
+ */
+static void fill_osr_temp_settings(uint8_t *reg_data, const struct bme280_settings *settings);
+
+/*!
+ * @brief This internal API sets the filter and/or standby duration settings
+ * in the sensor according to the settings selected by the user.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[in] desired_settings : variable to select the filter and/or
+ * standby duration settings.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+static int8_t set_filter_standby_settings(uint8_t desired_settings,
+        const struct bme280_settings *settings,
+        const struct bme280_dev *dev);
+
+/*!
+ * @brief This internal API fills the filter settings provided by the user
+ * in the data buffer so as to write in the sensor.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[out] reg_data : Variable which is filled according to the filter
+ * settings data provided by the user.
+ */
+static void fill_filter_settings(uint8_t *reg_data, const struct bme280_settings *settings);
+
+/*!
+ * @brief This internal API fills the standby duration settings provided by the
+ * user in the data buffer so as to write in the sensor.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[out] reg_data : Variable which is filled according to the standby
+ * settings data provided by the user.
+ */
+static void fill_standby_settings(uint8_t *reg_data, const struct bme280_settings *settings);
+
+/*!
+ * @brief This internal API parse the oversampling(pressure, temperature
+ * and humidity), filter and standby duration settings and store in the
+ * device structure.
+ *
+ * @param[out] dev : Structure instance of bme280_dev.
+ * @param[in] reg_data : Register data to be parsed.
+ */
+static void parse_device_settings(const uint8_t *reg_data, struct bme280_settings *settings);
+
+/*!
+ * @brief This internal API reloads the already existing device settings in the
+ * sensor after soft reset.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[in] settings : Pointer variable which contains the settings to
+ * be set in the sensor.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+static int8_t reload_device_settings(const struct bme280_settings *settings, const struct bme280_dev *dev);
+
+/****************** Global Function Definitions *******************************/
+
+/*!
+ *  @brief This API is the entry point.
+ *  It reads the chip-id and calibration data from the sensor.
+ */
+int8_t BME280::bme280_init(struct bme280_dev *dev)
+{
+    int8_t rslt;
+
+    /* chip id read try count */
+    uint8_t try_count = 5;
+    uint8_t chip_id = 0;
+
+    /* Check for null pointer in the device structure*/
+    rslt = null_ptr_check(dev);
+
+    /* Proceed if null check is fine */
+    if (rslt == BME280_OK) {
+        while (try_count) {
+            /* Read the chip-id of bme280 sensor */
+            rslt = bme280_get_regs(BME280_CHIP_ID_ADDR, &chip_id, 1, dev);
+
+            /* Check for chip id validity */
+            if ((rslt == BME280_OK) && (chip_id == BME280_CHIP_ID)) {
+                dev->chip_id = chip_id;
+
+                /* Reset the sensor */
+                rslt = bme280_soft_reset(dev);
+                if (rslt == BME280_OK) {
+                    /* Read the calibration data */
+                    rslt = get_calib_data(dev);
+                }
+                break;
+            }
+
+            /* Wait for 1 ms */
+            dev->delay_ms(1);
+            --try_count;
+        }
+
+        /* Chip id check failed */
+        if (!try_count) {
+            rslt = BME280_E_DEV_NOT_FOUND;
+        }
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API reads the data from the given register address of the sensor.
+ */
+int8_t BME280::bme280_get_regs(uint8_t reg_addr, uint8_t *reg_data, uint16_t len, const struct bme280_dev *dev)
+{
+    int8_t rslt;
+
+    /* Check for null pointer in the device structure*/
+    rslt = null_ptr_check(dev);
+
+    /* Proceed if null check is fine */
+    if (rslt == BME280_OK) {
+        /* If interface selected is SPI */
+        if (dev->intf != BME280_I2C_INTF) {
+            reg_addr = reg_addr | 0x80;
+        }
+
+        /* Read the data  */
+        rslt = dev->read(dev->dev_id, reg_addr, reg_data, len);
+
+        /* Check for communication error */
+        if (rslt != BME280_OK) {
+            rslt = BME280_E_COMM_FAIL;
+        }
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API writes the given data to the register address
+ * of the sensor.
+ */
+int8_t BME280::bme280_set_regs(uint8_t *reg_addr, const uint8_t *reg_data, uint8_t len, const struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t temp_buff[20]; /* Typically not to write more than 10 registers */
+
+    if (len > 10) {
+        len = 10;
+    }
+    uint16_t temp_len;
+    uint8_t reg_addr_cnt;
+
+    /* Check for null pointer in the device structure*/
+    rslt = null_ptr_check(dev);
+
+    /* Check for arguments validity */
+    if ((rslt == BME280_OK) && (reg_addr != NULL) && (reg_data != NULL)) {
+        if (len != 0) {
+            temp_buff[0] = reg_data[0];
+
+            /* If interface selected is SPI */
+            if (dev->intf != BME280_I2C_INTF) {
+                for (reg_addr_cnt = 0; reg_addr_cnt < len; reg_addr_cnt++) {
+                    reg_addr[reg_addr_cnt] = reg_addr[reg_addr_cnt] & 0x7F;
+                }
+            }
+
+            /* Burst write mode */
+            if (len > 1) {
+                /* Interleave register address w.r.t data for
+                 * burst write
+                 */
+                interleave_reg_addr(reg_addr, temp_buff, reg_data, len);
+                temp_len = ((len * 2) - 1);
+            } else {
+                temp_len = len;
+            }
+            rslt = dev->write(dev->dev_id, reg_addr[0], temp_buff, temp_len);
+
+            /* Check for communication error */
+            if (rslt != BME280_OK) {
+                rslt = BME280_E_COMM_FAIL;
+            }
+        } else {
+            rslt = BME280_E_INVALID_LEN;
+        }
+    } else {
+        rslt = BME280_E_NULL_PTR;
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API sets the oversampling, filter and standby duration
+ * (normal mode) settings in the sensor.
+ */
+int8_t BME280::bme280_set_sensor_settings(uint8_t desired_settings, const struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t sensor_mode;
+
+    /* Check for null pointer in the device structure*/
+    rslt = null_ptr_check(dev);
+
+    /* Proceed if null check is fine */
+    if (rslt == BME280_OK) {
+        rslt = bme280_get_sensor_mode(&sensor_mode, dev);
+        if ((rslt == BME280_OK) && (sensor_mode != BME280_SLEEP_MODE)) {
+            rslt = put_device_to_sleep(dev);
+        }
+        if (rslt == BME280_OK) {
+            /* Check if user wants to change oversampling
+             * settings
+             */
+            if (are_settings_changed(OVERSAMPLING_SETTINGS, desired_settings)) {
+                rslt = set_osr_settings(desired_settings, &dev->settings, dev);
+            }
+
+            /* Check if user wants to change filter and/or
+             * standby settings
+             */
+            if ((rslt == BME280_OK) && are_settings_changed(FILTER_STANDBY_SETTINGS, desired_settings)) {
+                rslt = set_filter_standby_settings(desired_settings, &dev->settings, dev);
+            }
+        }
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API gets the oversampling, filter and standby duration
+ * (normal mode) settings from the sensor.
+ */
+int8_t BME280::bme280_get_sensor_settings(struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t reg_data[4];
+
+    /* Check for null pointer in the device structure*/
+    rslt = null_ptr_check(dev);
+
+    /* Proceed if null check is fine */
+    if (rslt == BME280_OK) {
+        rslt = bme280_get_regs(BME280_CTRL_HUM_ADDR, reg_data, 4, dev);
+        if (rslt == BME280_OK) {
+            parse_device_settings(reg_data, &dev->settings);
+        }
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API sets the power mode of the sensor.
+ */
+int8_t BME280::bme280_set_sensor_mode(uint8_t sensor_mode, const struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t last_set_mode;
+
+    /* Check for null pointer in the device structure*/
+    rslt = null_ptr_check(dev);
+    if (rslt == BME280_OK) {
+        rslt = bme280_get_sensor_mode(&last_set_mode, dev);
+
+        /* If the sensor is not in sleep mode put the device to sleep
+         * mode
+         */
+        if ((rslt == BME280_OK) && (last_set_mode != BME280_SLEEP_MODE)) {
+            rslt = put_device_to_sleep(dev);
+        }
+
+        /* Set the power mode */
+        if (rslt == BME280_OK) {
+            rslt = write_power_mode(sensor_mode, dev);
+        }
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API gets the power mode of the sensor.
+ */
+int8_t BME280::bme280_get_sensor_mode(uint8_t *sensor_mode, const struct bme280_dev *dev)
+{
+    int8_t rslt;
+
+    /* Check for null pointer in the device structure*/
+    rslt = null_ptr_check(dev);
+    if (rslt == BME280_OK) {
+        /* Read the power mode register */
+        rslt = bme280_get_regs(BME280_PWR_CTRL_ADDR, sensor_mode, 1, dev);
+
+        /* Assign the power mode in the device structure */
+        *sensor_mode = BME280_GET_BITS_POS_0(*sensor_mode, BME280_SENSOR_MODE);
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API performs the soft reset of the sensor.
+ */
+int8_t BME280::bme280_soft_reset(const struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t reg_addr = BME280_RESET_ADDR;
+
+    /* 0xB6 is the soft reset command */
+    uint8_t soft_rst_cmd = 0xB6;
+
+    /* Check for null pointer in the device structure*/
+    rslt = null_ptr_check(dev);
+
+    /* Proceed if null check is fine */
+    if (rslt == BME280_OK) {
+        /* Write the soft reset command in the sensor */
+        rslt = bme280_set_regs(&reg_addr, &soft_rst_cmd, 1, dev);
+
+        /* As per data sheet, startup time is 2 ms. */
+        dev->delay_ms(2);
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API reads the pressure, temperature and humidity data from the
+ * sensor, compensates the data and store it in the bme280_data structure
+ * instance passed by the user.
+ */
+int8_t BME280::bme280_get_sensor_data(uint8_t sensor_comp, struct bme280_data *comp_data, struct bme280_dev *dev)
+{
+    int8_t rslt;
+
+    /* Array to store the pressure, temperature and humidity data read from
+     * the sensor
+     */
+    uint8_t reg_data[BME280_P_T_H_DATA_LEN] = { 0 };
+    struct bme280_uncomp_data uncomp_data = { 0 };
+
+    /* Check for null pointer in the device structure*/
+    rslt = null_ptr_check(dev);
+    if ((rslt == BME280_OK) && (comp_data != NULL)) {
+        /* Read the pressure and temperature data from the sensor */
+        rslt = bme280_get_regs(BME280_DATA_ADDR, reg_data, BME280_P_T_H_DATA_LEN, dev);
+        if (rslt == BME280_OK) {
+            /* Parse the read data from the sensor */
+            bme280_parse_sensor_data(reg_data, &uncomp_data);
+
+            /* Compensate the pressure and/or temperature and/or
+             * humidity data from the sensor
+             */
+            rslt = bme280_compensate_data(sensor_comp, &uncomp_data, comp_data, &dev->calib_data);
+        }
+    } else {
+        rslt = BME280_E_NULL_PTR;
+    }
+
+    return rslt;
+}
+
+/*!
+ *  @brief This API is used to parse the pressure, temperature and
+ *  humidity data and store it in the bme280_uncomp_data structure instance.
+ */
+void BME280::bme280_parse_sensor_data(const uint8_t *reg_data, struct bme280_uncomp_data *uncomp_data)
+{
+    /* Variables to store the sensor data */
+    uint32_t data_xlsb;
+    uint32_t data_lsb;
+    uint32_t data_msb;
+
+    /* Store the parsed register values for pressure data */
+    data_msb = (uint32_t)reg_data[0] << 12;
+    data_lsb = (uint32_t)reg_data[1] << 4;
+    data_xlsb = (uint32_t)reg_data[2] >> 4;
+    uncomp_data->pressure = data_msb | data_lsb | data_xlsb;
+
+    /* Store the parsed register values for temperature data */
+    data_msb = (uint32_t)reg_data[3] << 12;
+    data_lsb = (uint32_t)reg_data[4] << 4;
+    data_xlsb = (uint32_t)reg_data[5] >> 4;
+    uncomp_data->temperature = data_msb | data_lsb | data_xlsb;
+
+    /* Store the parsed register values for temperature data */
+    data_lsb = (uint32_t)reg_data[6] << 8;
+    data_msb = (uint32_t)reg_data[7];
+    uncomp_data->humidity = data_msb | data_lsb;
+}
+
+/*!
+ * @brief This API is used to compensate the pressure and/or
+ * temperature and/or humidity data according to the component selected
+ * by the user.
+ */
+int8_t BME280::bme280_compensate_data(uint8_t sensor_comp,
+                                      const struct bme280_uncomp_data *uncomp_data,
+                                      struct bme280_data *comp_data,
+                                      struct bme280_calib_data *calib_data)
+{
+    int8_t rslt = BME280_OK;
+
+    if ((uncomp_data != NULL) && (comp_data != NULL) && (calib_data != NULL)) {
+        /* Initialize to zero */
+        comp_data->temperature = 0;
+        comp_data->pressure = 0;
+        comp_data->humidity = 0;
+
+        /* If pressure or temperature component is selected */
+        if (sensor_comp & (BME280_PRESS | BME280_TEMP | BME280_HUM)) {
+            /* Compensate the temperature data */
+            comp_data->temperature = compensate_temperature(uncomp_data, calib_data);
+        }
+        if (sensor_comp & BME280_PRESS) {
+            /* Compensate the pressure data */
+            comp_data->pressure = compensate_pressure(uncomp_data, calib_data);
+        }
+        if (sensor_comp & BME280_HUM) {
+            /* Compensate the humidity data */
+            comp_data->humidity = compensate_humidity(uncomp_data, calib_data);
+        }
+    } else {
+        rslt = BME280_E_NULL_PTR;
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This internal API sets the oversampling settings for pressure,
+ * temperature and humidity in the sensor.
+ */
+static int8_t BME280::set_osr_settings(uint8_t desired_settings,
+                                       const struct bme280_settings *settings,
+                                       const struct bme280_dev *dev)
+{
+    int8_t rslt = BME280_W_INVALID_OSR_MACRO;
+
+    if (desired_settings & BME280_OSR_HUM_SEL) {
+        rslt = set_osr_humidity_settings(settings, dev);
+    }
+    if (desired_settings & (BME280_OSR_PRESS_SEL | BME280_OSR_TEMP_SEL)) {
+        rslt = set_osr_press_temp_settings(desired_settings, settings, dev);
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API sets the humidity oversampling settings of the sensor.
+ */
+static int8_t BME280::set_osr_humidity_settings(const struct bme280_settings *settings, const struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t ctrl_hum;
+    uint8_t ctrl_meas;
+    uint8_t reg_addr = BME280_CTRL_HUM_ADDR;
+
+    ctrl_hum = settings->osr_h & BME280_CTRL_HUM_MSK;
+
+    /* Write the humidity control value in the register */
+    rslt = bme280_set_regs(&reg_addr, &ctrl_hum, 1, dev);
+
+    /* Humidity related changes will be only effective after a
+     * write operation to ctrl_meas register
+     */
+    if (rslt == BME280_OK) {
+        reg_addr = BME280_CTRL_MEAS_ADDR;
+        rslt = bme280_get_regs(reg_addr, &ctrl_meas, 1, dev);
+        if (rslt == BME280_OK) {
+            rslt = bme280_set_regs(&reg_addr, &ctrl_meas, 1, dev);
+        }
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This API sets the pressure and/or temperature oversampling settings
+ * in the sensor according to the settings selected by the user.
+ */
+static int8_t BME280::set_osr_press_temp_settings(uint8_t desired_settings,
+        const struct bme280_settings *settings,
+        const struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t reg_addr = BME280_CTRL_MEAS_ADDR;
+    uint8_t reg_data;
+
+    rslt = bme280_get_regs(reg_addr, &reg_data, 1, dev);
+    if (rslt == BME280_OK) {
+        if (desired_settings & BME280_OSR_PRESS_SEL) {
+            fill_osr_press_settings(&reg_data, settings);
+        }
+        if (desired_settings & BME280_OSR_TEMP_SEL) {
+            fill_osr_temp_settings(&reg_data, settings);
+        }
+
+        /* Write the oversampling settings in the register */
+        rslt = bme280_set_regs(&reg_addr, &reg_data, 1, dev);
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This internal API sets the filter and/or standby duration settings
+ * in the sensor according to the settings selected by the user.
+ */
+static int8_t BME280::set_filter_standby_settings(uint8_t desired_settings,
+        const struct bme280_settings *settings,
+        const struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t reg_addr = BME280_CONFIG_ADDR;
+    uint8_t reg_data;
+
+    rslt = bme280_get_regs(reg_addr, &reg_data, 1, dev);
+    if (rslt == BME280_OK) {
+        if (desired_settings & BME280_FILTER_SEL) {
+            fill_filter_settings(&reg_data, settings);
+        }
+        if (desired_settings & BME280_STANDBY_SEL) {
+            fill_standby_settings(&reg_data, settings);
+        }
+
+        /* Write the oversampling settings in the register */
+        rslt = bme280_set_regs(&reg_addr, &reg_data, 1, dev);
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This internal API fills the filter settings provided by the user
+ * in the data buffer so as to write in the sensor.
+ */
+static void BME280::fill_filter_settings(uint8_t *reg_data, const struct bme280_settings *settings)
+{
+    *reg_data = BME280_SET_BITS(*reg_data, BME280_FILTER, settings->filter);
+}
+
+/*!
+ * @brief This internal API fills the standby duration settings provided by
+ * the user in the data buffer so as to write in the sensor.
+ */
+static void BME280::fill_standby_settings(uint8_t *reg_data, const struct bme280_settings *settings)
+{
+    *reg_data = BME280_SET_BITS(*reg_data, BME280_STANDBY, settings->standby_time);
+}
+
+/*!
+ * @brief This internal API fills the pressure oversampling settings provided by
+ * the user in the data buffer so as to write in the sensor.
+ */
+static void BME280::fill_osr_press_settings(uint8_t *reg_data, const struct bme280_settings *settings)
+{
+    *reg_data = BME280_SET_BITS(*reg_data, BME280_CTRL_PRESS, settings->osr_p);
+}
+
+/*!
+ * @brief This internal API fills the temperature oversampling settings
+ * provided by the user in the data buffer so as to write in the sensor.
+ */
+static void BME280::fill_osr_temp_settings(uint8_t *reg_data, const struct bme280_settings *settings)
+{
+    *reg_data = BME280_SET_BITS(*reg_data, BME280_CTRL_TEMP, settings->osr_t);
+}
+
+/*!
+ * @brief This internal API parse the oversampling(pressure, temperature
+ * and humidity), filter and standby duration settings and store in the
+ * device structure.
+ */
+static void BME280::parse_device_settings(const uint8_t *reg_data, struct bme280_settings *settings)
+{
+    settings->osr_h = BME280_GET_BITS_POS_0(reg_data[0], BME280_CTRL_HUM);
+    settings->osr_p = BME280_GET_BITS(reg_data[2], BME280_CTRL_PRESS);
+    settings->osr_t = BME280_GET_BITS(reg_data[2], BME280_CTRL_TEMP);
+    settings->filter = BME280_GET_BITS(reg_data[3], BME280_FILTER);
+    settings->standby_time = BME280_GET_BITS(reg_data[3], BME280_STANDBY);
+}
+
+/*!
+ * @brief This internal API writes the power mode in the sensor.
+ */
+static int8_t BME280::write_power_mode(uint8_t sensor_mode, const struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t reg_addr = BME280_PWR_CTRL_ADDR;
+
+    /* Variable to store the value read from power mode register */
+    uint8_t sensor_mode_reg_val;
+
+    /* Read the power mode register */
+    rslt = bme280_get_regs(reg_addr, &sensor_mode_reg_val, 1, dev);
+
+    /* Set the power mode */
+    if (rslt == BME280_OK) {
+        sensor_mode_reg_val = BME280_SET_BITS_POS_0(sensor_mode_reg_val, BME280_SENSOR_MODE, sensor_mode);
+
+        /* Write the power mode in the register */
+        rslt = bme280_set_regs(&reg_addr, &sensor_mode_reg_val, 1, dev);
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This internal API puts the device to sleep mode.
+ */
+static int8_t BME280::put_device_to_sleep(const struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t reg_data[4];
+    struct bme280_settings settings;
+
+    rslt = bme280_get_regs(BME280_CTRL_HUM_ADDR, reg_data, 4, dev);
+    if (rslt == BME280_OK) {
+        parse_device_settings(reg_data, &settings);
+        rslt = bme280_soft_reset(dev);
+        if (rslt == BME280_OK) {
+            rslt = reload_device_settings(&settings, dev);
+        }
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This internal API reloads the already existing device settings in
+ * the sensor after soft reset.
+ */
+static int8_t BME280::reload_device_settings(const struct bme280_settings *settings, const struct bme280_dev *dev)
+{
+    int8_t rslt;
+
+    rslt = set_osr_settings(BME280_ALL_SETTINGS_SEL, settings, dev);
+    if (rslt == BME280_OK) {
+        rslt = set_filter_standby_settings(BME280_ALL_SETTINGS_SEL, settings, dev);
+    }
+
+    return rslt;
+}
+
+#ifdef BME280_FLOAT_ENABLE
+
+/*!
+ * @brief This internal API is used to compensate the raw temperature data and
+ * return the compensated temperature data in double data type.
+ */
+static double BME280::compensate_temperature(const struct bme280_uncomp_data *uncomp_data, struct bme280_calib_data *calib_data)
+{
+    double var1;
+    double var2;
+    double temperature;
+    double temperature_min = -40;
+    double temperature_max = 85;
+
+    var1 = ((double)uncomp_data->temperature) / 16384.0 - ((double)calib_data->dig_T1) / 1024.0;
+    var1 = var1 * ((double)calib_data->dig_T2);
+    var2 = (((double)uncomp_data->temperature) / 131072.0 - ((double)calib_data->dig_T1) / 8192.0);
+    var2 = (var2 * var2) * ((double)calib_data->dig_T3);
+    calib_data->t_fine = (int32_t)(var1 + var2);
+    temperature = (var1 + var2) / 5120.0;
+    if (temperature < temperature_min) {
+        temperature = temperature_min;
+    } else if (temperature > temperature_max) {
+        temperature = temperature_max;
+    }
+
+    return temperature;
+}
+
+/*!
+ * @brief This internal API is used to compensate the raw pressure data and
+ * return the compensated pressure data in double data type.
+ */
+static double BME280::compensate_pressure(const struct bme280_uncomp_data *uncomp_data,
+        const struct bme280_calib_data *calib_data)
+{
+    double var1;
+    double var2;
+    double var3;
+    double pressure;
+    double pressure_min = 30000.0;
+    double pressure_max = 110000.0;
+
+    var1 = ((double)calib_data->t_fine / 2.0) - 64000.0;
+    var2 = var1 * var1 * ((double)calib_data->dig_P6) / 32768.0;
+    var2 = var2 + var1 * ((double)calib_data->dig_P5) * 2.0;
+    var2 = (var2 / 4.0) + (((double)calib_data->dig_P4) * 65536.0);
+    var3 = ((double)calib_data->dig_P3) * var1 * var1 / 524288.0;
+    var1 = (var3 + ((double)calib_data->dig_P2) * var1) / 524288.0;
+    var1 = (1.0 + var1 / 32768.0) * ((double)calib_data->dig_P1);
+
+    /* avoid exception caused by division by zero */
+    if (var1) {
+        pressure = 1048576.0 - (double) uncomp_data->pressure;
+        pressure = (pressure - (var2 / 4096.0)) * 6250.0 / var1;
+        var1 = ((double)calib_data->dig_P9) * pressure * pressure / 2147483648.0;
+        var2 = pressure * ((double)calib_data->dig_P8) / 32768.0;
+        pressure = pressure + (var1 + var2 + ((double)calib_data->dig_P7)) / 16.0;
+        if (pressure < pressure_min) {
+            pressure = pressure_min;
+        } else if (pressure > pressure_max) {
+            pressure = pressure_max;
+        }
+    } else { /* Invalid case */
+        pressure = pressure_min;
+    }
+
+    return pressure;
+}
+
+/*!
+ * @brief This internal API is used to compensate the raw humidity data and
+ * return the compensated humidity data in double data type.
+ */
+static double BME280::compensate_humidity(const struct bme280_uncomp_data *uncomp_data,
+        const struct bme280_calib_data *calib_data)
+{
+    double humidity;
+    double humidity_min = 0.0;
+    double humidity_max = 100.0;
+    double var1;
+    double var2;
+    double var3;
+    double var4;
+    double var5;
+    double var6;
+
+    var1 = ((double)calib_data->t_fine) - 76800.0;
+    var2 = (((double)calib_data->dig_H4) * 64.0 + (((double)calib_data->dig_H5) / 16384.0) * var1);
+    var3 = uncomp_data->humidity - var2;
+    var4 = ((double)calib_data->dig_H2) / 65536.0;
+    var5 = (1.0 + (((double)calib_data->dig_H3) / 67108864.0) * var1);
+    var6 = 1.0 + (((double)calib_data->dig_H6) / 67108864.0) * var1 * var5;
+    var6 = var3 * var4 * (var5 * var6);
+    humidity = var6 * (1.0 - ((double)calib_data->dig_H1) * var6 / 524288.0);
+    if (humidity > humidity_max) {
+        humidity = humidity_max;
+    } else if (humidity < humidity_min) {
+        humidity = humidity_min;
+    }
+
+    return humidity;
+}
+
+#else
+
+/*!
+ * @brief This internal API is used to compensate the raw temperature data and
+ * return the compensated temperature data in integer data type.
+ */
+static int32_t BME280::compensate_temperature(const struct bme280_uncomp_data *uncomp_data,
+        struct bme280_calib_data *calib_data)
+{
+    int32_t var1;
+    int32_t var2;
+    int32_t temperature;
+    int32_t temperature_min = -4000;
+    int32_t temperature_max = 8500;
+
+    var1 = (int32_t)((uncomp_data->temperature / 8) - ((int32_t)calib_data->dig_T1 * 2));
+    var1 = (var1 * ((int32_t)calib_data->dig_T2)) / 2048;
+    var2 = (int32_t)((uncomp_data->temperature / 16) - ((int32_t)calib_data->dig_T1));
+    var2 = (((var2 * var2) / 4096) * ((int32_t)calib_data->dig_T3)) / 16384;
+    calib_data->t_fine = var1 + var2;
+    temperature = (calib_data->t_fine * 5 + 128) / 256;
+    if (temperature < temperature_min) {
+        temperature = temperature_min;
+    } else if (temperature > temperature_max) {
+        temperature = temperature_max;
+    }
+
+    return temperature;
+}
+#ifdef BME280_64BIT_ENABLE
+
+/*!
+ * @brief This internal API is used to compensate the raw pressure data and
+ * return the compensated pressure data in integer data type with higher
+ * accuracy.
+ */
+static uint32_t BME280::compensate_pressure(const struct bme280_uncomp_data *uncomp_data,
+        const struct bme280_calib_data *calib_data)
+{
+    int64_t var1;
+    int64_t var2;
+    int64_t var3;
+    int64_t var4;
+    uint32_t pressure;
+    uint32_t pressure_min = 3000000;
+    uint32_t pressure_max = 11000000;
+
+    var1 = ((int64_t)calib_data->t_fine) - 128000;
+    var2 = var1 * var1 * (int64_t)calib_data->dig_P6;
+    var2 = var2 + ((var1 * (int64_t)calib_data->dig_P5) * 131072);
+    var2 = var2 + (((int64_t)calib_data->dig_P4) * 34359738368);
+    var1 = ((var1 * var1 * (int64_t)calib_data->dig_P3) / 256) + ((var1 * ((int64_t)calib_data->dig_P2) * 4096));
+    var3 = ((int64_t)1) * 140737488355328;
+    var1 = (var3 + var1) * ((int64_t)calib_data->dig_P1) / 8589934592;
+
+    /* To avoid divide by zero exception */
+    if (var1 != 0) {
+        var4 = 1048576 - uncomp_data->pressure;
+        var4 = (((var4 * INT64_C(2147483648)) - var2) * 3125) / var1;
+        var1 = (((int64_t)calib_data->dig_P9) * (var4 / 8192) * (var4 / 8192)) / 33554432;
+        var2 = (((int64_t)calib_data->dig_P8) * var4) / 524288;
+        var4 = ((var4 + var1 + var2) / 256) + (((int64_t)calib_data->dig_P7) * 16);
+        pressure = (uint32_t)(((var4 / 2) * 100) / 128);
+        if (pressure < pressure_min) {
+            pressure = pressure_min;
+        } else if (pressure > pressure_max) {
+            pressure = pressure_max;
+        }
+    } else {
+        pressure = pressure_min;
+    }
+
+    return pressure;
+}
+#else
+
+/*!
+ * @brief This internal API is used to compensate the raw pressure data and
+ * return the compensated pressure data in integer data type.
+ */
+static uint32_t BME280::compensate_pressure(const struct bme280_uncomp_data *uncomp_data,
+        const struct bme280_calib_data *calib_data)
+{
+    int32_t var1;
+    int32_t var2;
+    int32_t var3;
+    int32_t var4;
+    uint32_t var5;
+    uint32_t pressure;
+    uint32_t pressure_min = 30000;
+    uint32_t pressure_max = 110000;
+
+    var1 = (((int32_t)calib_data->t_fine) / 2) - (int32_t)64000;
+    var2 = (((var1 / 4) * (var1 / 4)) / 2048) * ((int32_t)calib_data->dig_P6);
+    var2 = var2 + ((var1 * ((int32_t)calib_data->dig_P5)) * 2);
+    var2 = (var2 / 4) + (((int32_t)calib_data->dig_P4) * 65536);
+    var3 = (calib_data->dig_P3 * (((var1 / 4) * (var1 / 4)) / 8192)) / 8;
+    var4 = (((int32_t)calib_data->dig_P2) * var1) / 2;
+    var1 = (var3 + var4) / 262144;
+    var1 = (((32768 + var1)) * ((int32_t)calib_data->dig_P1)) / 32768;
+
+    /* avoid exception caused by division by zero */
+    if (var1) {
+        var5 = (uint32_t)((uint32_t)1048576) - uncomp_data->pressure;
+        pressure = ((uint32_t)(var5 - (uint32_t)(var2 / 4096))) * 3125;
+        if (pressure < 0x80000000) {
+            pressure = (pressure << 1) / ((uint32_t)var1);
+        } else {
+            pressure = (pressure / (uint32_t)var1) * 2;
+        }
+        var1 = (((int32_t)calib_data->dig_P9) * ((int32_t)(((pressure / 8) * (pressure / 8)) / 8192))) / 4096;
+        var2 = (((int32_t)(pressure / 4)) * ((int32_t)calib_data->dig_P8)) / 8192;
+        pressure = (uint32_t)((int32_t)pressure + ((var1 + var2 + calib_data->dig_P7) / 16));
+        if (pressure < pressure_min) {
+            pressure = pressure_min;
+        } else if (pressure > pressure_max) {
+            pressure = pressure_max;
+        }
+    } else {
+        pressure = pressure_min;
+    }
+
+    return pressure;
+}
+#endif
+
+/*!
+ * @brief This internal API is used to compensate the raw humidity data and
+ * return the compensated humidity data in integer data type.
+ */
+static uint32_t BME280::compensate_humidity(const struct bme280_uncomp_data *uncomp_data,
+        const struct bme280_calib_data *calib_data)
+{
+    int32_t var1;
+    int32_t var2;
+    int32_t var3;
+    int32_t var4;
+    int32_t var5;
+    uint32_t humidity;
+    uint32_t humidity_max = 102400;
+
+    var1 = calib_data->t_fine - ((int32_t)76800);
+    var2 = (int32_t)(uncomp_data->humidity * 16384);
+    var3 = (int32_t)(((int32_t)calib_data->dig_H4) * 1048576);
+    var4 = ((int32_t)calib_data->dig_H5) * var1;
+    var5 = (((var2 - var3) - var4) + (int32_t)16384) / 32768;
+    var2 = (var1 * ((int32_t)calib_data->dig_H6)) / 1024;
+    var3 = (var1 * ((int32_t)calib_data->dig_H3)) / 2048;
+    var4 = ((var2 * (var3 + (int32_t)32768)) / 1024) + (int32_t)2097152;
+    var2 = ((var4 * ((int32_t)calib_data->dig_H2)) + 8192) / 16384;
+    var3 = var5 * var2;
+    var4 = ((var3 / 32768) * (var3 / 32768)) / 128;
+    var5 = var3 - ((var4 * ((int32_t)calib_data->dig_H1)) / 16);
+    var5 = (var5 < 0 ? 0 : var5);
+    var5 = (var5 > 419430400 ? 419430400 : var5);
+    humidity = (uint32_t)(var5 / 4096);
+    if (humidity > humidity_max) {
+        humidity = humidity_max;
+    }
+
+    return humidity;
+}
+#endif
+
+/*!
+ * @brief This internal API reads the calibration data from the sensor, parse
+ * it and store in the device structure.
+ */
+static int8_t BME280::get_calib_data(struct bme280_dev *dev)
+{
+    int8_t rslt;
+    uint8_t reg_addr = BME280_TEMP_PRESS_CALIB_DATA_ADDR;
+
+    /* Array to store calibration data */
+    uint8_t calib_data[BME280_TEMP_PRESS_CALIB_DATA_LEN] = { 0 };
+
+    /* Read the calibration data from the sensor */
+    rslt = bme280_get_regs(reg_addr, calib_data, BME280_TEMP_PRESS_CALIB_DATA_LEN, dev);
+    if (rslt == BME280_OK) {
+        /* Parse temperature and pressure calibration data and store
+         * it in device structure
+         */
+        parse_temp_press_calib_data(calib_data, dev);
+        reg_addr = BME280_HUMIDITY_CALIB_DATA_ADDR;
+
+        /* Read the humidity calibration data from the sensor */
+        rslt = bme280_get_regs(reg_addr, calib_data, BME280_HUMIDITY_CALIB_DATA_LEN, dev);
+        if (rslt == BME280_OK) {
+            /* Parse humidity calibration data and store it in
+             * device structure
+             */
+            parse_humidity_calib_data(calib_data, dev);
+        }
+    }
+
+    return rslt;
+}
+
+/*!
+ * @brief This internal API interleaves the register address between the
+ * register data buffer for burst write operation.
+ */
+static void BME280::interleave_reg_addr(const uint8_t *reg_addr, uint8_t *temp_buff, const uint8_t *reg_data, uint8_t len)
+{
+    uint8_t index;
+
+    for (index = 1; index < len; index++) {
+        temp_buff[(index * 2) - 1] = reg_addr[index];
+        temp_buff[index * 2] = reg_data[index];
+    }
+}
+
+/*!
+ *  @brief This internal API is used to parse the temperature and
+ *  pressure calibration data and store it in device structure.
+ */
+static void BME280::parse_temp_press_calib_data(const uint8_t *reg_data, struct bme280_dev *dev)
+{
+    struct bme280_calib_data *calib_data = &dev->calib_data;
+
+    calib_data->dig_T1 = BME280_CONCAT_BYTES(reg_data[1], reg_data[0]);
+    calib_data->dig_T2 = (int16_t)BME280_CONCAT_BYTES(reg_data[3], reg_data[2]);
+    calib_data->dig_T3 = (int16_t)BME280_CONCAT_BYTES(reg_data[5], reg_data[4]);
+    calib_data->dig_P1 = BME280_CONCAT_BYTES(reg_data[7], reg_data[6]);
+    calib_data->dig_P2 = (int16_t)BME280_CONCAT_BYTES(reg_data[9], reg_data[8]);
+    calib_data->dig_P3 = (int16_t)BME280_CONCAT_BYTES(reg_data[11], reg_data[10]);
+    calib_data->dig_P4 = (int16_t)BME280_CONCAT_BYTES(reg_data[13], reg_data[12]);
+    calib_data->dig_P5 = (int16_t)BME280_CONCAT_BYTES(reg_data[15], reg_data[14]);
+    calib_data->dig_P6 = (int16_t)BME280_CONCAT_BYTES(reg_data[17], reg_data[16]);
+    calib_data->dig_P7 = (int16_t)BME280_CONCAT_BYTES(reg_data[19], reg_data[18]);
+    calib_data->dig_P8 = (int16_t)BME280_CONCAT_BYTES(reg_data[21], reg_data[20]);
+    calib_data->dig_P9 = (int16_t)BME280_CONCAT_BYTES(reg_data[23], reg_data[22]);
+    calib_data->dig_H1 = reg_data[25];
+}
+
+/*!
+ *  @brief This internal API is used to parse the humidity calibration data
+ *  and store it in device structure.
+ */
+static void BME280::parse_humidity_calib_data(const uint8_t *reg_data, struct bme280_dev *dev)
+{
+    struct bme280_calib_data *calib_data = &dev->calib_data;
+    int16_t dig_H4_lsb;
+    int16_t dig_H4_msb;
+    int16_t dig_H5_lsb;
+    int16_t dig_H5_msb;
+
+    calib_data->dig_H2 = (int16_t)BME280_CONCAT_BYTES(reg_data[1], reg_data[0]);
+    calib_data->dig_H3 = reg_data[2];
+    dig_H4_msb = (int16_t)(int8_t)reg_data[3] * 16;
+    dig_H4_lsb = (int16_t)(reg_data[4] & 0x0F);
+    calib_data->dig_H4 = dig_H4_msb | dig_H4_lsb;
+    dig_H5_msb = (int16_t)(int8_t)reg_data[5] * 16;
+    dig_H5_lsb = (int16_t)(reg_data[4] >> 4);
+    calib_data->dig_H5 = dig_H5_msb | dig_H5_lsb;
+    calib_data->dig_H6 = (int8_t)reg_data[6];
+}
+
+/*!
+ * @brief This internal API is used to identify the settings which the user
+ * wants to modify in the sensor.
+ */
+static uint8_t BME280::are_settings_changed(uint8_t sub_settings, uint8_t desired_settings)
+{
+    uint8_t settings_changed = FALSE;
+
+    if (sub_settings & desired_settings) {
+        /* User wants to modify this particular settings */
+        settings_changed = TRUE;
+    } else {
+        /* User don't want to modify this particular settings */
+        settings_changed = FALSE;
+    }
+
+    return settings_changed;
+}
+
+/*!
+ * @brief This internal API is used to validate the device structure pointer for
+ * null conditions.
+ */
+static int8_t BME280::null_ptr_check(const struct bme280_dev *dev)
+{
+    int8_t rslt;
+
+    if ((dev == NULL) || (dev->read == NULL) || (dev->write == NULL) || (dev->delay_ms == NULL)) {
+        /* Device structure pointer is not valid */
+        rslt = BME280_E_NULL_PTR;
+    } else {
+        /* Device structure is fine */
+        rslt = BME280_OK;
+    }
+
+    return rslt;
+}
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