Standalone driver for the Bosch BME280 environmental sensor. More...

Collaboration diagram for BME280 Driver:

Data Structures
struct	driver_bme280_data_t
	BME280 measurement data. More...

struct	driver_bme280_t
	BME280 driver instance. More...

Enumerations
enum	driver_bme280_oversampling_t { DRIVER_BME280_OVERSAMPLING_NONE = 0, DRIVER_BME280_OVERSAMPLING_1X = 1, DRIVER_BME280_OVERSAMPLING_2X = 2, DRIVER_BME280_OVERSAMPLING_4X = 3, DRIVER_BME280_OVERSAMPLING_8X = 4, DRIVER_BME280_OVERSAMPLING_16X = 5 }
	BME280 oversampling settings. More...

enum	driver_bme280_filter_t { DRIVER_BME280_FILTER_OFF = 0, DRIVER_BME280_FILTER_2 = 1, DRIVER_BME280_FILTER_4 = 2, DRIVER_BME280_FILTER_8 = 3, DRIVER_BME280_FILTER_16 = 4 }
	BME280 IIR filter coefficients. More...

Functions
bool	driver_bme280_init_i2c (driver_bme280_t driver, hw_i2c_t i2c, uint8_t addr_offset)
	Initialize BME280 with I2C interface and default settingsInitializes with default settings: 1x oversampling for all sensors, filter off. More...

bool	driver_bme280_init_i2c_with_config (driver_bme280_t driver, hw_i2c_t i2c, uint8_t addr_offset, driver_bme280_oversampling_t temp_os, driver_bme280_oversampling_t press_os, driver_bme280_oversampling_t hum_os, driver_bme280_filter_t filter)
	Initialize BME280 with I2C interface and custom settingsAllows configuration of oversampling and filter settings. More...

bool	driver_bme280_valid (driver_bme280_t *driver)
	Check if driver instance is valid. More...

void	driver_bme280_finalize (driver_bme280_t *driver)
	Finalize and power down BME280. More...

void	driver_bme280_set_temp_offset (driver_bme280_t *driver, float offset)
	Set temperature offset for calibrationUse this to compensate for self-heating or other temperature offsets. More...

bool	driver_bme280_read_data (driver_bme280_t driver, driver_bme280_data_t data)
	Read all sensor data (temperature, pressure, humidity)Triggers a forced measurement (single shot), waits for completion, and reads all three sensor values in a single transaction. More...

float	driver_bme280_calculate_altitude (const driver_bme280_data_t *data, float sea_level_pressure)
	Calculate altitude from pressureUses the international barometric formula. More...

float	driver_bme280_calculate_sea_level_pressure (const driver_bme280_data_t *data, float altitude)
	Calculate sea level pressure from altitude. More...

Detailed Description

Standalone driver for the Bosch BME280 environmental sensor.

Provides temperature, pressure, and humidity measurements.

Enumeration Type Documentation

◆ driver_bme280_filter_t

enum driver_bme280_filter_t

BME280 IIR filter coefficients.

Enumerator
DRIVER_BME280_FILTER_OFF	Filter off.
DRIVER_BME280_FILTER_2	Filter coefficient 2.
DRIVER_BME280_FILTER_4	Filter coefficient 4.
DRIVER_BME280_FILTER_8	Filter coefficient 8.
DRIVER_BME280_FILTER_16	Filter coefficient 16.

Definition at line 35 of file drivers_bme280.h.

              {
   DRIVER_BME280_FILTER_OFF = 0, 
   DRIVER_BME280_FILTER_2 = 1,   
   DRIVER_BME280_FILTER_4 = 2,   
   DRIVER_BME280_FILTER_8 = 3,   
   DRIVER_BME280_FILTER_16 = 4   
 } driver_bme280_filter_t;

◆ driver_bme280_oversampling_t

enum driver_bme280_oversampling_t

BME280 oversampling settings.

Enumerator
DRIVER_BME280_OVERSAMPLING_NONE	No oversampling (output set to 0)
DRIVER_BME280_OVERSAMPLING_1X	Oversampling ×1.
DRIVER_BME280_OVERSAMPLING_2X	Oversampling ×2.
DRIVER_BME280_OVERSAMPLING_4X	Oversampling ×4.
DRIVER_BME280_OVERSAMPLING_8X	Oversampling ×8.
DRIVER_BME280_OVERSAMPLING_16X	Oversampling ×16.

Definition at line 22 of file drivers_bme280.h.

              {
   DRIVER_BME280_OVERSAMPLING_NONE = 0, 
   DRIVER_BME280_OVERSAMPLING_1X = 1,   
   DRIVER_BME280_OVERSAMPLING_2X = 2,   
   DRIVER_BME280_OVERSAMPLING_4X = 3,   
   DRIVER_BME280_OVERSAMPLING_8X = 4,   
   DRIVER_BME280_OVERSAMPLING_16X = 5   
 } driver_bme280_oversampling_t;

Function Documentation

◆ driver_bme280_calculate_altitude()

float driver_bme280_calculate_altitude	(	const driver_bme280_data_t *	data,
		float	sea_level_pressure
	)

Calculate altitude from pressureUses the international barometric formula.

Parameters

data	Pointer to measurement data containing pressure
sea_level_pressure	Sea level pressure in Pa (default: 101325 Pa)

Returns: Altitude in meters

◆ driver_bme280_calculate_sea_level_pressure()

float driver_bme280_calculate_sea_level_pressure	(	const driver_bme280_data_t *	data,
		float	altitude
	)

Calculate sea level pressure from altitude.

Parameters

data	Pointer to measurement data containing pressure
altitude	Current altitude in meters

Returns: Sea level pressure in Pa

◆ driver_bme280_finalize()

void driver_bme280_finalize ( driver_bme280_t * driver )

Finalize and power down BME280.

Parameters

driver Pointer to driver structure

◆ driver_bme280_init_i2c()

bool driver_bme280_init_i2c	(	driver_bme280_t *	driver,
		hw_i2c_t *	i2c,
		uint8_t	addr_offset
	)

Initialize BME280 with I2C interface and default settingsInitializes with default settings: 1x oversampling for all sensors, filter off.

Parameters

driver	Pointer to driver structure
i2c	Pointer to initialized I2C interface
addr_offset	Address offset (0 for 0x76, 1 for 0x77)

Returns: true if initialization succeeded, false otherwise

◆ driver_bme280_init_i2c_with_config()

bool driver_bme280_init_i2c_with_config	(	driver_bme280_t *	driver,
		hw_i2c_t *	i2c,
		uint8_t	addr_offset,
		driver_bme280_oversampling_t	temp_os,
		driver_bme280_oversampling_t	press_os,
		driver_bme280_oversampling_t	hum_os,
		driver_bme280_filter_t	filter
	)

Initialize BME280 with I2C interface and custom settingsAllows configuration of oversampling and filter settings.

Parameters

driver	Pointer to driver structure
i2c	Pointer to initialized I2C interface
addr_offset	Address offset (0 for 0x76, 1 for 0x77)
temp_os	Temperature oversampling
press_os	Pressure oversampling
hum_os	Humidity oversampling
filter	IIR filter coefficient

Returns: true if initialization succeeded, false otherwise

◆ driver_bme280_read_data()

bool driver_bme280_read_data	(	driver_bme280_t *	driver,
		driver_bme280_data_t *	data
	)

Read all sensor data (temperature, pressure, humidity)Triggers a forced measurement (single shot), waits for completion, and reads all three sensor values in a single transaction.

The sensor returns to sleep mode after the measurement.

Parameters

driver	Pointer to driver structure
data	Pointer to structure to receive measurement data

Returns: true if successful, false otherwise

◆ driver_bme280_set_temp_offset()

void driver_bme280_set_temp_offset	(	driver_bme280_t *	driver,
		float	offset
	)

Set temperature offset for calibrationUse this to compensate for self-heating or other temperature offsets.

For example, if the sensor reads 33°C but ambient is 22°C, use -11°C offset.

Parameters

driver	Pointer to driver structure
offset	Temperature offset in °C (can be negative)

◆ driver_bme280_valid()

bool driver_bme280_valid ( driver_bme280_t * driver )

Check if driver instance is valid.

Parameters

driver Pointer to driver structure

Returns: true if valid, false otherwise

objc

Data Structures

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

◆ driver_bme280_filter_t

◆ driver_bme280_oversampling_t

Function Documentation

◆ driver_bme280_calculate_altitude()

◆ driver_bme280_calculate_sea_level_pressure()

◆ driver_bme280_finalize()

◆ driver_bme280_init_i2c()

◆ driver_bme280_init_i2c_with_config()

◆ driver_bme280_read_data()

◆ driver_bme280_set_temp_offset()

◆ driver_bme280_valid()