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Posted to commits@mynewt.apache.org by an...@apache.org on 2018/11/23 16:16:44 UTC

[mynewt-core] 12/26: apps: Add sample bus_test app

This is an automated email from the ASF dual-hosted git repository.

andk pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/mynewt-core.git

commit 24f071f4d5978c898f43e3d48841109dd5b1d09d
Author: Andrzej Kaczmarek <an...@codecoup.pl>
AuthorDate: Mon Nov 5 17:00:04 2018 +0100

    apps: Add sample bus_test app
    
    This is a simple app for evaluating hw/bus driver.
---
 .../bme280_node/include/bme280_node/bme280_node.h  |   48 +
 apps/bus_test/bme280_node/pkg.yml                  |   27 +
 apps/bus_test/bme280_node/src/bme280_node.c        |  154 +++
 apps/bus_test/bme280_node/src/ext/bme280.c         | 1273 ++++++++++++++++++++
 apps/bus_test/bme280_node/src/ext/bme280.h         |  240 ++++
 apps/bus_test/bme280_node/src/ext/bme280_defs.h    |  362 ++++++
 .../lis2dh_node/include/lis2dh_node/lis2dh_node.h  |   46 +
 apps/bus_test/lis2dh_node/pkg.yml                  |   27 +
 apps/bus_test/lis2dh_node/src/lis2dh_node.c        |   94 ++
 apps/bus_test/pkg.yml                              |   39 +
 apps/bus_test/src/main.c                           |  231 ++++
 apps/bus_test/syscfg.yml                           |   62 +
 12 files changed, 2603 insertions(+)

diff --git a/apps/bus_test/bme280_node/include/bme280_node/bme280_node.h b/apps/bus_test/bme280_node/include/bme280_node/bme280_node.h
new file mode 100644
index 0000000..91463e4
--- /dev/null
+++ b/apps/bus_test/bme280_node/include/bme280_node/bme280_node.h
@@ -0,0 +1,48 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#ifndef BME280_NODE_H_
+#define BME280_NODE_H_
+
+#include <stddef.h>
+#include <stdint.h>
+#include "os/os_dev.h"
+#include "sys/queue.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct bme280_node_measurement {
+    float temperature;
+    float pressure;
+    float humidity;
+};
+
+int
+bme280_node_read(struct os_dev *dev, struct bme280_node_measurement *measurment);
+
+int
+bme280_node_i2c_create(const char *name, const struct bus_i2c_node_cfg *cfg);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* BME280_NODE_H_ */
diff --git a/apps/bus_test/bme280_node/pkg.yml b/apps/bus_test/bme280_node/pkg.yml
new file mode 100644
index 0000000..b6f2251
--- /dev/null
+++ b/apps/bus_test/bme280_node/pkg.yml
@@ -0,0 +1,27 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+# 
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+pkg.name: apps/bus_test/bme280_node
+pkg.description:
+pkg.author: "Apache Mynewt <de...@mynewt.apache.org>"
+pkg.homepage: "http://mynewt.apache.org/"
+pkg.keywords:
+
+pkg.deps:
+    - "@apache-mynewt-core/hw/bus/i2c"
diff --git a/apps/bus_test/bme280_node/src/bme280_node.c b/apps/bus_test/bme280_node/src/bme280_node.c
new file mode 100644
index 0000000..120ecc1
--- /dev/null
+++ b/apps/bus_test/bme280_node/src/bme280_node.c
@@ -0,0 +1,154 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "os/mynewt.h"
+#include "console/console.h"
+#include "bus/bus.h"
+#include "bus/i2c.h"
+#include "bme280_node/bme280_node.h"
+#include "ext/bme280.h"
+
+#define BME280_ODEV(_node) ((struct os_dev *)(&(_node)->i2c_node))
+
+struct bme280_node {
+    struct bme280_dev bme280_dev;
+    struct bus_i2c_node i2c_node;
+};
+
+static struct bme280_node g_bme280_node;
+
+struct reg_val {
+    uint8_t addr;
+    uint8_t val[32];
+};
+
+static int8_t
+bme280_read(uint8_t dev_id, uint8_t reg_addr, uint8_t *data, uint16_t len)
+{
+    struct reg_val reg;
+    int rc;
+
+    assert(len <= sizeof(reg.val));
+
+    reg.addr = reg_addr;
+
+    rc = bus_node_simple_write_read_transact(BME280_ODEV(&g_bme280_node),
+                                             &reg.addr, 1, &reg.val[0], len);
+    if (!rc) {
+        memcpy(data, &reg.val[0], len);
+    }
+
+    return rc;
+}
+
+static int8_t
+bme280_write(uint8_t dev_id, uint8_t reg_addr, uint8_t *data, uint16_t len)
+{
+    struct reg_val reg;
+    int rc;
+
+    assert(len <= sizeof(reg.val));
+
+    reg.addr = reg_addr;
+    memcpy(reg.val, data, len);
+
+    rc = bus_node_simple_write(BME280_ODEV(&g_bme280_node), &reg.addr, 1 + len);
+
+    return rc;
+}
+
+static void
+bme280_delay_ms(uint32_t period)
+{
+    os_cputime_delay_usecs(period * 1000);
+}
+
+static void
+open_node_cb(struct bus_node *node)
+{
+    struct bme280_node *bme280_node = CONTAINER_OF(node, struct bme280_node, i2c_node);
+    struct bme280_dev *bme280_dev = &bme280_node->bme280_dev;
+    int rc;
+
+    console_printf("%s: node %p\n", __func__, node);
+
+    bme280_dev->dev_id = 0x76;
+    bme280_dev->intf = BME280_I2C_INTF;
+    bme280_dev->read = bme280_read;
+    bme280_dev->write = bme280_write;
+    bme280_dev->delay_ms = bme280_delay_ms;
+    rc = bme280_init(bme280_dev);
+    SYSINIT_PANIC_ASSERT(rc == 0);
+
+    bme280_dev->settings.osr_h = BME280_OVERSAMPLING_1X;
+    bme280_dev->settings.osr_p = BME280_OVERSAMPLING_16X;
+    bme280_dev->settings.osr_t = BME280_OVERSAMPLING_2X;
+    bme280_dev->settings.filter = BME280_FILTER_COEFF_16;
+
+    rc = bme280_set_sensor_settings(BME280_OSR_PRESS_SEL | BME280_OSR_TEMP_SEL |
+                                    BME280_OSR_HUM_SEL | BME280_FILTER_SEL,
+                                    bme280_dev);
+    assert(rc == 0);
+}
+
+static void
+close_node_cb(struct bus_node *node)
+{
+    console_printf("%s: node %p\n", __func__, node);
+}
+
+int
+bme280_node_read(struct os_dev *dev, struct bme280_node_measurement *measurement)
+{
+    struct bme280_node *bme280_node = CONTAINER_OF(dev, struct bme280_node, i2c_node);
+    struct bme280_data sensor_data;
+    int rc;
+
+    assert(measurement);
+
+    rc = bme280_set_sensor_mode(BME280_FORCED_MODE, &bme280_node->bme280_dev);
+    assert(rc == 0);
+
+    rc = bme280_get_sensor_data(0x07, &sensor_data, &bme280_node->bme280_dev);
+    assert(rc == 0);
+
+    measurement->temperature = sensor_data.temperature / 100.0f;
+    measurement->pressure = sensor_data.pressure / 10000.0f;
+    measurement->humidity = sensor_data.humidity / 1000.0f;
+
+    return 0;
+}
+
+int
+bme280_node_i2c_create(const char *name, const struct bus_i2c_node_cfg *cfg)
+{
+    struct bus_node_callbacks cbs = {
+        .init = NULL,
+        .open = open_node_cb,
+        .close = close_node_cb,
+    };
+    int rc;
+
+    bus_node_set_callbacks((struct os_dev *)&g_bme280_node.i2c_node, &cbs);
+
+    rc = bus_i2c_node_create(name, &g_bme280_node.i2c_node,
+                             (struct bus_i2c_node_cfg *)cfg);
+
+    return rc;
+}
diff --git a/apps/bus_test/bme280_node/src/ext/bme280.c b/apps/bus_test/bme280_node/src/ext/bme280.c
new file mode 100644
index 0000000..bd903b8
--- /dev/null
+++ b/apps/bus_test/bme280_node/src/ext/bme280.c
@@ -0,0 +1,1273 @@
+/**\mainpage
+ * Copyright (C) 2016 - 2017 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		14 Feb 2018
+ * Version	3.3.4
+ *
+ */
+
+/*! @file bme280.c
+    @brief Sensor driver for BME280 sensor */
+#include "../../../bme280_node/src/ext/bme280.h"
+
+/**\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_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_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_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_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_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_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_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_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_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_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_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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 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 * 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 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 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 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 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 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 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 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 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;
+}
diff --git a/apps/bus_test/bme280_node/src/ext/bme280.h b/apps/bus_test/bme280_node/src/ext/bme280.h
new file mode 100644
index 0000000..d29d862
--- /dev/null
+++ b/apps/bus_test/bme280_node/src/ext/bme280.h
@@ -0,0 +1,240 @@
+/**
+ * Copyright (C) 2016 - 2017 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.h
+ * @date	14 Feb 2018
+ * @version	3.3.4
+ * @brief
+ *
+ */
+/*! @file bme280.h
+    @brief Sensor driver for BME280 sensor */
+/*!
+ * @defgroup BME280 SENSOR API
+ * @{*/
+#ifndef BME280_H_
+#define BME280_H_
+
+/*! CPP guard */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Header includes */
+#include "../../../bme280_node/src/ext/bme280_defs.h"
+
+/*!
+ *  @brief This API is the entry point.
+ *  It reads the chip-id and calibration data from the sensor.
+ *
+ *  @param[in,out] dev : Structure instance of bme280_dev
+ *
+ *  @return Result of API execution status
+ *  @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+int8_t bme280_init(struct bme280_dev *dev);
+
+/*!
+ * @brief This API writes the given data to the register address
+ * of the sensor.
+ *
+ * @param[in] reg_addr : Register address from where the data to be written.
+ * @param[in] reg_data : Pointer to data buffer which is to be written
+ * in the sensor.
+ * @param[in] len : No of bytes of data to write..
+ * @param[in] dev : Structure instance of bme280_dev.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+int8_t bme280_set_regs(uint8_t *reg_addr, const uint8_t *reg_data, uint8_t len, const struct bme280_dev *dev);
+
+/*!
+ * @brief This API reads the data from the given register address of the sensor.
+ *
+ * @param[in] reg_addr : Register address from where the data to be read
+ * @param[out] reg_data : Pointer to data buffer to store the read data.
+ * @param[in] len : No of bytes of data to be read.
+ * @param[in] dev : Structure instance of bme280_dev.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+int8_t bme280_get_regs(uint8_t reg_addr, uint8_t *reg_data, uint16_t len, const struct bme280_dev *dev);
+
+/*!
+ * @brief This API sets the oversampling, filter and standby duration
+ * (normal mode) settings in the sensor.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[in] desired_settings : Variable used to select the settings which
+ * are to be set in the sensor.
+ *
+ * @note : Below are the macros to be used by the user for selecting the
+ * desired settings. User can do OR operation of these macros for configuring
+ * multiple settings.
+ *
+ * Macros		  |   Functionality
+ * -----------------------|----------------------------------------------
+ * BME280_OSR_PRESS_SEL    |   To set pressure oversampling.
+ * BME280_OSR_TEMP_SEL     |   To set temperature oversampling.
+ * BME280_OSR_HUM_SEL    |   To set humidity oversampling.
+ * BME280_FILTER_SEL     |   To set filter setting.
+ * BME280_STANDBY_SEL  |   To set standby duration setting.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error.
+ */
+int8_t bme280_set_sensor_settings(uint8_t desired_settings, const struct bme280_dev *dev);
+
+/*!
+ * @brief This API gets the oversampling, filter and standby duration
+ * (normal mode) settings from the sensor.
+ *
+ * @param[in,out] dev : Structure instance of bme280_dev.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error.
+ */
+int8_t bme280_get_sensor_settings(struct bme280_dev *dev);
+
+/*!
+ * @brief This API sets the power mode of the sensor.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[in] sensor_mode : Variable which contains the power mode to be set.
+ *
+ *    sensor_mode           |   Macros
+ * ---------------------|-------------------
+ *     0                | BME280_SLEEP_MODE
+ *     1                | BME280_FORCED_MODE
+ *     3                | BME280_NORMAL_MODE
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+int8_t bme280_set_sensor_mode(uint8_t sensor_mode,
+				const struct bme280_dev *dev);
+
+/*!
+ * @brief This API gets the power mode of the sensor.
+ *
+ * @param[in] dev : Structure instance of bme280_dev.
+ * @param[out] sensor_mode : Pointer variable to store the power mode.
+ *
+ *   sensor_mode            |   Macros
+ * ---------------------|-------------------
+ *     0                | BME280_SLEEP_MODE
+ *     1                | BME280_FORCED_MODE
+ *     3                | BME280_NORMAL_MODE
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+int8_t bme280_get_sensor_mode(uint8_t *sensor_mode, const struct bme280_dev *dev);
+
+/*!
+ * @brief This API performs the soft reset 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.
+ */
+int8_t bme280_soft_reset(const struct bme280_dev *dev);
+
+/*!
+ * @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.
+ *
+ * @param[in] sensor_comp : Variable which selects which data to be read from
+ * the sensor.
+ *
+ * sensor_comp |   Macros
+ * ------------|-------------------
+ *     1       | BME280_PRESS
+ *     2       | BME280_TEMP
+ *     4       | BME280_HUM
+ *     7       | BME280_ALL
+ *
+ * @param[out] comp_data : Structure instance of bme280_data.
+ * @param[in] dev : Structure instance of bme280_dev.
+ *
+ * @return Result of API execution status
+ * @retval zero -> Success / +ve value -> Warning / -ve value -> Error
+ */
+int8_t bme280_get_sensor_data(uint8_t sensor_comp, struct bme280_data *comp_data, struct bme280_dev *dev);
+
+/*!
+ *  @brief This API is used to parse the pressure, temperature and
+ *  humidity data and store it in the bme280_uncomp_data structure instance.
+ *
+ *  @param[in] reg_data     : Contains register data which needs to be parsed
+ *  @param[out] uncomp_data : Contains the uncompensated pressure, temperature
+ *  and humidity data.
+ */
+void bme280_parse_sensor_data(const uint8_t *reg_data, struct bme280_uncomp_data *uncomp_data);
+
+/*!
+ * @brief This API is used to compensate the pressure and/or
+ * temperature and/or humidity data according to the component selected by the
+ * user.
+ *
+ * @param[in] sensor_comp : Used to select pressure and/or temperature and/or
+ * humidity.
+ * @param[in] uncomp_data : Contains the uncompensated pressure, temperature and
+ * humidity data.
+ * @param[out] comp_data : Contains the compensated pressure and/or temperature
+ * and/or humidity data.
+ * @param[in] calib_data : Pointer to the calibration data structure.
+ *
+ * @return Result of API execution status.
+ * @retval zero -> Success / -ve value -> Error
+ */
+int8_t 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);
+
+#ifdef __cplusplus
+}
+#endif /* End of CPP guard */
+#endif /* BME280_H_ */
+/** @}*/
diff --git a/apps/bus_test/bme280_node/src/ext/bme280_defs.h b/apps/bus_test/bme280_node/src/ext/bme280_defs.h
new file mode 100644
index 0000000..06abc8a
--- /dev/null
+++ b/apps/bus_test/bme280_node/src/ext/bme280_defs.h
@@ -0,0 +1,362 @@
+/**
+ * Copyright (C) 2016 - 2017 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_defs.h
+ * @date	14 Feb 2018
+ * @version	3.3.4
+ * @brief
+ *
+ */
+
+/*! @file bme280_defs.h
+    @brief Sensor driver for BME280 sensor */
+/*!
+ * @defgroup BME280 SENSOR API
+ * @brief
+ * @{*/
+#ifndef BME280_DEFS_H_
+#define BME280_DEFS_H_
+
+/********************************************************/
+/* header includes */
+#ifdef __KERNEL__
+#include <linux/types.h>
+#include <linux/kernel.h>
+#else
+#include <stdint.h>
+#include <stddef.h>
+#endif
+
+/********************************************************/
+/*! @name		Common macros		        */
+/********************************************************/
+
+#if !defined(UINT8_C) && !defined(INT8_C)
+#define INT8_C(x)       S8_C(x)
+#define UINT8_C(x)      U8_C(x)
+#endif
+
+#if !defined(UINT16_C) && !defined(INT16_C)
+#define INT16_C(x)      S16_C(x)
+#define UINT16_C(x)     U16_C(x)
+#endif
+
+#if !defined(INT32_C) && !defined(UINT32_C)
+#define INT32_C(x)      S32_C(x)
+#define UINT32_C(x)     U32_C(x)
+#endif
+
+#if !defined(INT64_C) && !defined(UINT64_C)
+#define INT64_C(x)      S64_C(x)
+#define UINT64_C(x)     U64_C(x)
+#endif
+
+/**@}*/
+
+/**\name C standard macros */
+#ifndef NULL
+#ifdef __cplusplus
+#define NULL   0
+#else
+#define NULL   ((void *) 0)
+#endif
+#endif
+/********************************************************/
+
+#ifndef BME280_FLOAT_ENABLE
+/* #define BME280_FLOAT_ENABLE */
+#endif
+
+#ifndef BME280_FLOAT_ENABLE
+#ifndef BME280_64BIT_ENABLE
+#define BME280_64BIT_ENABLE
+#endif
+#endif
+
+#ifndef TRUE
+#define TRUE                UINT8_C(1)
+#endif
+#ifndef FALSE
+#define FALSE               UINT8_C(0)
+#endif
+
+/**\name I2C addresses */
+#define BME280_I2C_ADDR_PRIM	UINT8_C(0x76)
+#define BME280_I2C_ADDR_SEC		UINT8_C(0x77)
+
+/**\name BME280 chip identifier */
+#define BME280_CHIP_ID  UINT8_C(0x60)
+
+/**\name Register Address */
+#define BME280_CHIP_ID_ADDR					UINT8_C(0xD0)
+#define BME280_RESET_ADDR					UINT8_C(0xE0)
+#define BME280_TEMP_PRESS_CALIB_DATA_ADDR	UINT8_C(0x88)
+#define BME280_HUMIDITY_CALIB_DATA_ADDR		UINT8_C(0xE1)
+#define BME280_PWR_CTRL_ADDR				UINT8_C(0xF4)
+#define BME280_CTRL_HUM_ADDR				UINT8_C(0xF2)
+#define BME280_CTRL_MEAS_ADDR				UINT8_C(0xF4)
+#define BME280_CONFIG_ADDR					UINT8_C(0xF5)
+#define BME280_DATA_ADDR					UINT8_C(0xF7)
+
+/**\name API success code */
+#define BME280_OK					INT8_C(0)
+
+/**\name API error codes */
+#define BME280_E_NULL_PTR			INT8_C(-1)
+#define BME280_E_DEV_NOT_FOUND		INT8_C(-2)
+#define BME280_E_INVALID_LEN		INT8_C(-3)
+#define BME280_E_COMM_FAIL			INT8_C(-4)
+#define BME280_E_SLEEP_MODE_FAIL	INT8_C(-5)
+
+/**\name API warning codes */
+#define BME280_W_INVALID_OSR_MACRO      INT8_C(1)
+
+/**\name Macros related to size */
+#define BME280_TEMP_PRESS_CALIB_DATA_LEN	UINT8_C(26)
+#define BME280_HUMIDITY_CALIB_DATA_LEN		UINT8_C(7)
+#define BME280_P_T_H_DATA_LEN				UINT8_C(8)
+
+/**\name Sensor power modes */
+#define	BME280_SLEEP_MODE		UINT8_C(0x00)
+#define	BME280_FORCED_MODE		UINT8_C(0x01)
+#define	BME280_NORMAL_MODE		UINT8_C(0x03)
+
+/**\name Macro to combine two 8 bit data's to form a 16 bit data */
+#define BME280_CONCAT_BYTES(msb, lsb)     (((uint16_t)msb << 8) | (uint16_t)lsb)
+
+#define BME280_SET_BITS(reg_data, bitname, data) \
+				((reg_data & ~(bitname##_MSK)) | \
+				((data << bitname##_POS) & bitname##_MSK))
+#define BME280_SET_BITS_POS_0(reg_data, bitname, data) \
+				((reg_data & ~(bitname##_MSK)) | \
+				(data & bitname##_MSK))
+
+#define BME280_GET_BITS(reg_data, bitname)  ((reg_data & (bitname##_MSK)) >> \
+							(bitname##_POS))
+#define BME280_GET_BITS_POS_0(reg_data, bitname)  (reg_data & (bitname##_MSK))
+
+/**\name Macros for bit masking */
+#define BME280_SENSOR_MODE_MSK	UINT8_C(0x03)
+#define BME280_SENSOR_MODE_POS	UINT8_C(0x00)
+
+#define BME280_CTRL_HUM_MSK		UINT8_C(0x07)
+#define BME280_CTRL_HUM_POS		UINT8_C(0x00)
+
+#define BME280_CTRL_PRESS_MSK	UINT8_C(0x1C)
+#define BME280_CTRL_PRESS_POS	UINT8_C(0x02)
+
+#define BME280_CTRL_TEMP_MSK	UINT8_C(0xE0)
+#define BME280_CTRL_TEMP_POS	UINT8_C(0x05)
+
+#define BME280_FILTER_MSK		UINT8_C(0x1C)
+#define BME280_FILTER_POS		UINT8_C(0x02)
+
+#define BME280_STANDBY_MSK		UINT8_C(0xE0)
+#define BME280_STANDBY_POS		UINT8_C(0x05)
+
+/**\name Sensor component selection macros
+   These values are internal for API implementation. Don't relate this to
+   data sheet.*/
+#define BME280_PRESS		UINT8_C(1)
+#define BME280_TEMP			UINT8_C(1 << 1)
+#define BME280_HUM			UINT8_C(1 << 2)
+#define BME280_ALL			UINT8_C(0x07)
+
+/**\name Settings selection macros */
+#define BME280_OSR_PRESS_SEL		UINT8_C(1)
+#define BME280_OSR_TEMP_SEL			UINT8_C(1 << 1)
+#define BME280_OSR_HUM_SEL			UINT8_C(1 << 2)
+#define BME280_FILTER_SEL			UINT8_C(1 << 3)
+#define BME280_STANDBY_SEL			UINT8_C(1 << 4)
+#define BME280_ALL_SETTINGS_SEL		UINT8_C(0x1F)
+
+/**\name Oversampling macros */
+#define BME280_NO_OVERSAMPLING		UINT8_C(0x00)
+#define BME280_OVERSAMPLING_1X		UINT8_C(0x01)
+#define BME280_OVERSAMPLING_2X		UINT8_C(0x02)
+#define BME280_OVERSAMPLING_4X		UINT8_C(0x03)
+#define BME280_OVERSAMPLING_8X		UINT8_C(0x04)
+#define BME280_OVERSAMPLING_16X		UINT8_C(0x05)
+
+/**\name Standby duration selection macros */
+#define BME280_STANDBY_TIME_1_MS              (0x00)
+#define BME280_STANDBY_TIME_62_5_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 Filter coefficient selection macros */
+#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)
+
+/*!
+ * @brief Interface selection Enums
+ */
+enum bme280_intf {
+	/*! SPI interface */
+	BME280_SPI_INTF,
+	/*! I2C interface */
+	BME280_I2C_INTF
+};
+
+/*!
+ * @brief Type definitions
+ */
+typedef int8_t (*bme280_com_fptr_t)(uint8_t dev_id, uint8_t reg_addr,
+		uint8_t *data, uint16_t len);
+
+typedef void (*bme280_delay_fptr_t)(uint32_t period);
+
+/*!
+ * @brief Calibration data
+ */
+struct bme280_calib_data {
+ /**
+ * @ Trim Variables
+ */
+/**@{*/
+	uint16_t dig_T1;
+	int16_t dig_T2;
+	int16_t dig_T3;
+	uint16_t dig_P1;
+	int16_t dig_P2;
+	int16_t dig_P3;
+	int16_t dig_P4;
+	int16_t dig_P5;
+	int16_t dig_P6;
+	int16_t dig_P7;
+	int16_t dig_P8;
+	int16_t dig_P9;
+	uint8_t  dig_H1;
+	int16_t dig_H2;
+	uint8_t  dig_H3;
+	int16_t dig_H4;
+	int16_t dig_H5;
+	int8_t  dig_H6;
+	int32_t t_fine;
+/**@}*/
+};
+
+/*!
+ * @brief bme280 sensor structure which comprises of temperature, pressure and
+ * humidity data
+ */
+#ifdef BME280_FLOAT_ENABLE
+struct bme280_data {
+	/*! Compensated pressure */
+	double pressure;
+	/*! Compensated temperature */
+	double temperature;
+	/*! Compensated humidity */
+	double humidity;
+};
+#else
+struct bme280_data {
+	/*! Compensated pressure */
+	uint32_t pressure;
+	/*! Compensated temperature */
+	int32_t temperature;
+	/*! Compensated humidity */
+	uint32_t humidity;
+};
+#endif /* BME280_USE_FLOATING_POINT */
+
+/*!
+ * @brief bme280 sensor structure which comprises of uncompensated temperature,
+ * pressure and humidity data
+ */
+struct bme280_uncomp_data {
+	/*! un-compensated pressure */
+	uint32_t pressure;
+	/*! un-compensated temperature */
+	uint32_t temperature;
+	/*! un-compensated humidity */
+	uint32_t humidity;
+};
+
+/*!
+ * @brief bme280 sensor settings structure which comprises of mode,
+ * oversampling and filter settings.
+ */
+struct bme280_settings {
+	/*! pressure oversampling */
+	uint8_t osr_p;
+	/*! temperature oversampling */
+	uint8_t osr_t;
+	/*! humidity oversampling */
+	uint8_t osr_h;
+	/*! filter coefficient */
+	uint8_t filter;
+	/*! standby time */
+	uint8_t standby_time;
+};
+
+/*!
+ * @brief bme280 device structure
+ */
+struct bme280_dev {
+	/*! Chip Id */
+	uint8_t chip_id;
+	/*! Device Id */
+	uint8_t dev_id;
+	/*! SPI/I2C interface */
+	enum bme280_intf intf;
+	/*! Read function pointer */
+	bme280_com_fptr_t read;
+	/*! Write function pointer */
+	bme280_com_fptr_t write;
+	/*! Delay function pointer */
+	bme280_delay_fptr_t delay_ms;
+	/*! Trim data */
+	struct bme280_calib_data calib_data;
+	/*! Sensor settings */
+	struct bme280_settings settings;
+};
+
+#endif /* BME280_DEFS_H_ */
+/** @}*/
+/** @}*/
diff --git a/apps/bus_test/lis2dh_node/include/lis2dh_node/lis2dh_node.h b/apps/bus_test/lis2dh_node/include/lis2dh_node/lis2dh_node.h
new file mode 100644
index 0000000..f97a66c
--- /dev/null
+++ b/apps/bus_test/lis2dh_node/include/lis2dh_node/lis2dh_node.h
@@ -0,0 +1,46 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#ifndef LIS2DH_NODE_H_
+#define LIS2DH_NODE_H_
+
+#include <stdint.h>
+#include "os/os_dev.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct lis2dh_node_pos {
+    uint16_t x;
+    uint16_t y;
+    uint16_t z;
+};
+
+int
+lis2dh_node_read(struct os_dev *dev, struct lis2dh_node_pos *pos);
+
+int
+lis2dh_node_i2c_create(const char *name, const struct bus_i2c_node_cfg *cfg);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LIS2DH_NODE_H_ */
diff --git a/apps/bus_test/lis2dh_node/pkg.yml b/apps/bus_test/lis2dh_node/pkg.yml
new file mode 100644
index 0000000..08f3b72
--- /dev/null
+++ b/apps/bus_test/lis2dh_node/pkg.yml
@@ -0,0 +1,27 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+# 
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+pkg.name: apps/bus_test/lis2dh_node
+pkg.description:
+pkg.author: "Apache Mynewt <de...@mynewt.apache.org>"
+pkg.homepage: "http://mynewt.apache.org/"
+pkg.keywords:
+
+pkg.deps:
+    - "@apache-mynewt-core/hw/bus/i2c"
diff --git a/apps/bus_test/lis2dh_node/src/lis2dh_node.c b/apps/bus_test/lis2dh_node/src/lis2dh_node.c
new file mode 100644
index 0000000..47e14ae
--- /dev/null
+++ b/apps/bus_test/lis2dh_node/src/lis2dh_node.c
@@ -0,0 +1,94 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "os/mynewt.h"
+#include "console/console.h"
+#include "bus/bus.h"
+#include "bus/i2c.h"
+#include "lis2dh_node/lis2dh_node.h"
+
+static struct bus_i2c_node g_lis2dh_node;
+
+struct reg_val {
+    uint8_t addr;
+    uint8_t val[32];
+};
+
+static void
+open_node_cb(struct bus_node *node)
+{
+    struct os_dev *odev = (struct os_dev *)node;
+    struct reg_val reg;
+    int rc;
+
+    console_printf("%s: node %p\n", __func__, node);
+
+    reg.addr = 0x0f; /* WHO_AM_I */
+    rc = bus_node_simple_write_read_transact(odev, &reg.addr, 1, reg.val, 1);
+    assert(rc == 0);
+    assert(reg.val[0] == 0x33);
+
+    reg.addr = 0x20; /* CTRL_REG1 */
+    reg.val[0] = 0x37;
+    rc = bus_node_simple_write(odev, &reg.addr, 2);
+    assert(rc == 0);
+}
+
+static void
+close_node_cb(struct bus_node *node)
+{
+    console_printf("%s: node %p\n", __func__, node);
+}
+
+int
+lis2dh_node_read(struct os_dev *node, struct lis2dh_node_pos *pos)
+{
+    struct reg_val reg;
+    int rc;
+
+    assert(pos);
+
+    reg.addr = 0x80 | 0x28; /* OUT_X_L */
+    rc = bus_node_simple_write_read_transact(node, &reg.addr, 1, reg.val, 6);
+    assert(rc == 0);
+
+    pos->x = get_le16(&reg.val[0]);
+    pos->y = get_le16(&reg.val[2]);
+    pos->z = get_le16(&reg.val[4]);
+
+    return 0;
+}
+
+int
+lis2dh_node_i2c_create(const char *name, const struct bus_i2c_node_cfg *cfg)
+{
+    struct bus_node_callbacks cbs = {
+        .init = NULL,
+        .open = open_node_cb,
+        .close = close_node_cb,
+    };
+    int rc;
+
+    bus_node_set_callbacks((struct os_dev *)&g_lis2dh_node, &cbs);
+
+    rc = bus_i2c_node_create(name, &g_lis2dh_node,
+                             (struct bus_i2c_node_cfg *)cfg);
+
+    return rc;
+}
diff --git a/apps/bus_test/pkg.yml b/apps/bus_test/pkg.yml
new file mode 100644
index 0000000..db30ec9
--- /dev/null
+++ b/apps/bus_test/pkg.yml
@@ -0,0 +1,39 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+# 
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+pkg.name: apps/bus_test
+pkg.type: app
+pkg.description:
+pkg.author: "Apache Mynewt <de...@mynewt.apache.org>"
+pkg.homepage: "http://mynewt.apache.org/"
+pkg.keywords:
+
+pkg.deps:
+    - "@apache-mynewt-core/kernel/os"
+    - "@apache-mynewt-core/sys/console/full"
+    - "@apache-mynewt-core/sys/log/full"
+    - "@apache-mynewt-core/sys/stats/stub"
+
+pkg.deps.APP_USE_LIS2DH_NODE:
+    - "@apache-mynewt-core/apps/bus_test/lis2dh_node"
+pkg.deps.APP_USE_BME280_NODE:
+    - "@apache-mynewt-core/apps/bus_test/bme280_node"
+pkg.deps.APP_USE_BME280_SENSOR:
+    - "@apache-mynewt-core/hw/drivers/sensors/bme280"
+    - "@apache-mynewt-core/hw/sensor"
diff --git a/apps/bus_test/src/main.c b/apps/bus_test/src/main.c
new file mode 100644
index 0000000..3869f24
--- /dev/null
+++ b/apps/bus_test/src/main.c
@@ -0,0 +1,231 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "os/mynewt.h"
+#include "bus/bus.h"
+#include "bus/i2c.h"
+#include "bus/spi.h"
+#include "console/console.h"
+#include "hal/hal_gpio.h"
+#include "sensor/sensor.h"
+#include "sensor/temperature.h"
+
+#if MYNEWT_VAL(APP_USE_BME280_NODE)
+#include "bme280_node/bme280_node.h"
+#endif
+#if MYNEWT_VAL(APP_USE_LIS2DH_NODE)
+#include "lis2dh_node/lis2dh_node.h"
+#endif
+#if MYNEWT_VAL(APP_USE_BME280_SENSOR)
+#include "bme280/bme280.h"
+#endif
+
+#if MYNEWT_VAL(APP_USE_BME280_NODE) || MYNEWT_VAL(APP_USE_BME280_SENSOR)
+#if MYNEWT_VAL(APP_USE_BME280_SENSOR)
+static const struct bus_i2c_node_cfg g_bme280_node_i2c_cfg = {
+    .node_cfg = {
+        .bus_name = MYNEWT_VAL(BME280_NODE_BUS_NAME),
+    },
+    .addr = MYNEWT_VAL(BME280_NODE_I2C_ADDRESS),
+    .freq = MYNEWT_VAL(BME280_NODE_I2C_FREQUENCY),
+};
+#endif
+
+static const struct bus_spi_node_cfg g_bme280_node_spi_cfg = {
+    .node_cfg = {
+        .bus_name = MYNEWT_VAL(BME280_NODE_BUS_NAME),
+    },
+    .pin_cs = MYNEWT_VAL(BME280_NODE_SPI_CS_PIN),
+    .mode = BUS_SPI_MODE_0,
+    .data_order = BUS_SPI_DATA_ORDER_MSB,
+    .freq = MYNEWT_VAL(BME280_NODE_SPI_FREQUENCY),
+};
+
+static struct os_dev *g_bme280_node;
+#endif
+
+#if MYNEWT_VAL(APP_USE_LIS2DH_NODE)
+static const struct bus_i2c_node_cfg g_lis2dh_node_i2c_cfg = {
+    .node_cfg = {
+        .bus_name = MYNEWT_VAL(LIS2DH_NODE_BUS_NAME),
+    },
+    .addr = MYNEWT_VAL(LIS2DH_NODE_I2C_ADDRESS),
+    .freq = MYNEWT_VAL(LIS2DH_NODE_I2C_FREQUENCY),
+};
+
+static struct os_dev *g_lis2dh_node;
+#endif
+
+#if MYNEWT_VAL(APP_USE_BME280_SENSOR)
+static struct bme280 bme280;
+static struct sensor *bme280_sensor;
+struct sensor_listener bme280_listener;
+
+#endif
+
+static struct os_callout co_read;
+
+static void
+co_read_cb(struct os_event *ev)
+{
+#if MYNEWT_VAL(APP_USE_BME280_NODE)
+    struct bme280_node_measurement meas;
+#endif
+#if MYNEWT_VAL(APP_USE_LIS2DH_NODE)
+    struct lis2dh_node_pos pos;
+#endif
+    int rc;
+
+#if MYNEWT_VAL(APP_USE_BME280_NODE)
+    rc = bme280_node_read(g_bme280_node, &meas);
+    assert(rc == 0);
+    console_printf("T=%f P=%f H=%f\n", meas.temperature, meas.pressure, meas.humidity);
+#endif
+
+#if MYNEWT_VAL(APP_USE_LIS2DH_NODE)
+    rc = lis2dh_node_read(g_lis2dh_node, &pos);
+    assert(rc == 0);
+    console_printf("X=%04x Y=%04x Z=%04x\n", pos.x, pos.y, pos.z);
+#endif
+
+    rc = os_callout_reset(&co_read, os_time_ms_to_ticks32(1000));
+    assert(rc == 0);
+}
+
+#if MYNEWT_VAL(APP_USE_BME280_SENSOR)
+static int
+bme280_sensor_listener_cb(struct sensor *sensor, void *arg,
+                          void *data, sensor_type_t type)
+{
+    struct sensor_temp_data *std;
+
+    std = data;
+
+    console_printf("T=%f (valid %d)\n", std->std_temp, std->std_temp_is_valid);
+
+    return 0;
+}
+
+
+static void
+bme280_sensor_configure(void)
+{
+    struct os_dev *dev;
+    struct bme280_cfg cfg;
+    int rc;
+
+    dev = os_dev_open("bme280", OS_TIMEOUT_NEVER, NULL);
+    assert(dev != NULL);
+
+    memset(&cfg, 0, sizeof(cfg));
+
+    cfg.bc_mode = BME280_MODE_FORCED;
+    cfg.bc_iir = BME280_FILTER_OFF;
+    cfg.bc_sby_dur = BME280_STANDBY_MS_0_5;
+    cfg.bc_boc[0].boc_type = SENSOR_TYPE_RELATIVE_HUMIDITY;
+    cfg.bc_boc[1].boc_type = SENSOR_TYPE_PRESSURE;
+    cfg.bc_boc[2].boc_type = SENSOR_TYPE_AMBIENT_TEMPERATURE;
+    cfg.bc_boc[0].boc_oversample = BME280_SAMPLING_X1;
+    cfg.bc_boc[1].boc_oversample = BME280_SAMPLING_X1;
+    cfg.bc_boc[2].boc_oversample = BME280_SAMPLING_X1;
+    cfg.bc_s_mask = SENSOR_TYPE_AMBIENT_TEMPERATURE|
+                       SENSOR_TYPE_PRESSURE|
+                       SENSOR_TYPE_RELATIVE_HUMIDITY;
+
+    rc = bme280_config((struct bme280 *)dev, &cfg);
+    assert(rc == 0);
+
+    os_dev_close(dev);
+}
+#endif
+
+int
+main(int argc, char **argv)
+{
+    int rc;
+
+    sysinit();
+
+#if MYNEWT_VAL(APP_USE_BME280_NODE)
+    rc = bme280_node_i2c_create("bme280", &g_bme280_node_i2c_cfg);
+    assert(rc == 0);
+
+    g_bme280_node = os_dev_open("bme280", 0, NULL);
+    assert(g_bme280_node);
+#endif
+
+#if MYNEWT_VAL(APP_USE_LIS2DH_NODE)
+    rc = lis2dh_node_i2c_create("lis2dh", &g_lis2dh_node_i2c_cfg);
+    assert(rc == 0);
+
+    g_lis2dh_node = os_dev_open("lis2dh", 0, NULL);
+    assert(g_lis2dh_node);
+#endif
+
+#if MYNEWT_VAL(APP_USE_BME280_SENSOR)
+    /* XXX hack for now... */
+    if (!strncmp("i2c", MYNEWT_VAL(BME280_NODE_BUS_NAME), 3)) {
+        /* For I2C SDO pin is address select pin */
+        hal_gpio_init_out(MYNEWT_VAL(SPI_1_MASTER_PIN_MISO), 0);
+        /* Make sure CSB is not set to low state as it will switch BME280 to SPI */
+        hal_gpio_init_out(MYNEWT_VAL(BME280_NODE_SPI_CS_PIN), 1);
+
+        rc = bme280_create_i2c_dev(&bme280.i2c_node, "bme280",
+                                   &g_bme280_node_i2c_cfg);
+        assert(rc == 0);
+    } else if (!strncmp("spi", MYNEWT_VAL(BME280_NODE_BUS_NAME), 3)) {
+        rc = bme280_create_spi_dev(&bme280.spi_node, "bme280",
+                                   &g_bme280_node_spi_cfg);
+        assert(rc == 0);
+    } else {
+        assert(0);
+    }
+
+    g_bme280_node = os_dev_open("bme280", 0, NULL);
+    assert(g_bme280_node);
+
+    bme280_sensor_configure();
+
+    bme280_sensor = sensor_mgr_find_next_bydevname("bme280", NULL);
+    assert(bme280_sensor);
+
+    bme280_listener.sl_sensor_type = SENSOR_TYPE_AMBIENT_TEMPERATURE;
+    bme280_listener.sl_func = bme280_sensor_listener_cb;
+    bme280_listener.sl_arg = NULL;
+
+    rc = sensor_register_listener(bme280_sensor, &bme280_listener);
+    assert(rc == 0);
+
+    rc = sensor_set_poll_rate_ms("bme280", 500);
+    assert(rc == 0);
+#endif
+
+    os_callout_init(&co_read, os_eventq_dflt_get(), co_read_cb, NULL);
+
+#if MYNEWT_VAL(APP_USE_BME280_NODE) || MYNEWT_VAL(APP_USE_LIS2DH_NODE)
+    rc = os_callout_reset(&co_read, os_time_ms_to_ticks32(1000));
+    assert(rc == 0);
+#endif
+
+    while (1) {
+        os_eventq_run(os_eventq_dflt_get());
+    }
+
+    return (0);
+}
diff --git a/apps/bus_test/syscfg.yml b/apps/bus_test/syscfg.yml
new file mode 100644
index 0000000..0ff54ff
--- /dev/null
+++ b/apps/bus_test/syscfg.yml
@@ -0,0 +1,62 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#  http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+syscfg.defs:
+    APP_USE_BME280_NODE:
+        value: 1
+        restrictions:
+            - '!APP_USE_BME280_SENSOR'
+    APP_USE_LIS2DH_NODE:
+        value: 1
+    APP_USE_BME280_SENSOR:
+        value: 0
+        restrictions:
+            - '!APP_USE_BME280_NODE'
+
+    BME280_NODE_BUS_NAME:
+        description: Name of bus device where BME280 is attached
+        value: '"i2c0"'
+    BME280_NODE_I2C_ADDRESS:
+        description: I2C address of BME280 device
+        value: 0x76
+    BME280_NODE_I2C_FREQUENCY:
+        description: I2C frequency [kHz] to use for BME280
+        value: 100
+    BME280_NODE_SPI_FREQUENCY:
+        description: SPI frequency [kHz] to use for BME280
+        value: 4000
+    BME280_NODE_SPI_CS_PIN:
+        description: Chip select pin for BME280
+        value: 35
+
+    LIS2DH_NODE_BUS_NAME:
+        description: Name of bus device where LIS2DH is attached
+        value: '"i2c0"'
+    LIS2DH_NODE_I2C_ADDRESS:
+        description: I2C address of LIS2DH device
+        value: 0x18
+    LIS2DH_NODE_I2C_FREQUENCY:
+        description: I2C frequency [kHz] to use for LIS2DH
+        value: 400
+
+
+syscfg.vals:
+    BUS_DEBUG_OS_DEV: 1
+    FLOAT_USER: 1
+    SENSOR_CLI: 1
+    SHELL_TASK: 1