Class that stores state and functions for interacting with BME280 IC. More...

#include <Adafruit_BME280.h>

Classes
struct	config
	config register More...

struct	ctrl_hum
	ctrl_hum register More...

struct	ctrl_meas
	ctrl_meas register More...

Public Types
enum	sensor_sampling { SAMPLING_NONE = 0b000, SAMPLING_X1 = 0b001, SAMPLING_X2 = 0b010, SAMPLING_X4 = 0b011, SAMPLING_X8 = 0b100, SAMPLING_X16 = 0b101 }
	sampling rates

enum	sensor_mode { MODE_SLEEP = 0b00, MODE_FORCED = 0b01, MODE_NORMAL = 0b11 }
	power modes

enum	sensor_filter { FILTER_OFF = 0b000, FILTER_X2 = 0b001, FILTER_X4 = 0b010, FILTER_X8 = 0b011, FILTER_X16 = 0b100 }
	filter values

enum	standby_duration { STANDBY_MS_0_5 = 0b000, STANDBY_MS_10 = 0b110, STANDBY_MS_20 = 0b111, STANDBY_MS_62_5 = 0b001, STANDBY_MS_125 = 0b010, STANDBY_MS_250 = 0b011, STANDBY_MS_500 = 0b100, STANDBY_MS_1000 = 0b101 }
	standby duration in ms

Public Member Functions
	Adafruit_BME280 ()
	class constructor

	Adafruit_BME280 (int8_t cspin, SPIClass *theSPI=&SPI)
	class constructor if using hardware SPI More...

	Adafruit_BME280 (int8_t cspin, int8_t mosipin, int8_t misopin, int8_t sckpin)
	class constructor if using software SPI More...

bool	begin (uint8_t addr=BME280_ADDRESS, TwoWire *theWire=&Wire)
	Initialise sensor with given parameters / settings. More...

bool	init ()
	Initialise sensor with given parameters / settings. More...

void	setSampling (sensor_mode mode=MODE_NORMAL, sensor_sampling tempSampling=SAMPLING_X16, sensor_sampling pressSampling=SAMPLING_X16, sensor_sampling humSampling=SAMPLING_X16, sensor_filter filter=FILTER_OFF, standby_duration duration=STANDBY_MS_0_5)
	setup sensor with given parameters / settings More...

bool	takeForcedMeasurement (void)
	Take a new measurement (only possible in forced mode) More...

float	readTemperature (void)
	Returns the temperature from the sensor. More...

float	readPressure (void)
	Returns the pressure from the sensor. More...

float	readHumidity (void)
	Returns the humidity from the sensor. More...

float	readAltitude (float seaLevel)

float	seaLevelForAltitude (float altitude, float pressure)

uint32_t	sensorID (void)

float	getTemperatureCompensation (void)

void	setTemperatureCompensation (float)

Adafruit_Sensor *	getTemperatureSensor (void)
	Gets an Adafruit Unified Sensor object for the temp sensor component. More...

Adafruit_Sensor *	getPressureSensor (void)
	Gets an Adafruit Unified Sensor object for the pressure sensor component. More...

Adafruit_Sensor *	getHumiditySensor (void)
	Gets an Adafruit Unified Sensor object for the humidity sensor component. More...

Protected Member Functions
void	readCoefficients (void)
	Reads the factory-set coefficients.

bool	isReadingCalibration (void)
	return true if chip is busy reading cal data More...

void	write8 (byte reg, byte value)
	Writes an 8 bit value over I2C or SPI. More...

uint8_t	read8 (byte reg)
	Reads an 8 bit value over I2C or SPI. More...

uint16_t	read16 (byte reg)
	Reads a 16 bit value over I2C or SPI. More...

uint32_t	read24 (byte reg)
	Reads a 24 bit value over I2C. More...

int16_t	readS16 (byte reg)
	Reads a signed 16 bit value over I2C or SPI. More...

uint16_t	read16_LE (byte reg)
	Reads a signed 16 bit little endian value over I2C or SPI. More...

int16_t	readS16_LE (byte reg)
	Reads a signed little endian 16 bit value over I2C or SPI. More...

Protected Attributes
Adafruit_I2CDevice *	i2c_dev = NULL
	Pointer to I2C bus interface.

Adafruit_SPIDevice *	spi_dev = NULL
	Pointer to SPI bus interface.

Adafruit_BME280_Temp *	temp_sensor = NULL
	Adafruit_Sensor compat temperature sensor component.

Adafruit_BME280_Pressure *	pressure_sensor = NULL
	Adafruit_Sensor compat pressure sensor component.

Adafruit_BME280_Humidity *	humidity_sensor = NULL
	Adafruit_Sensor compat humidity sensor component.

uint8_t	_i2caddr
	I2C addr for the TwoWire interface.

int32_t	_sensorID
	ID of the BME Sensor.

int32_t	t_fine

int32_t	t_fine_adjust = 0

bme280_calib_data	_bme280_calib
	here calibration data is stored

config	_configReg
	config register object

ctrl_meas	_measReg
	measurement register object

ctrl_hum	_humReg
	hum register object

Detailed Description

Class that stores state and functions for interacting with BME280 IC.

Constructor & Destructor Documentation

◆ Adafruit_BME280() [1/2]

Adafruit_BME280::Adafruit_BME280	(	int8_t	cspin,
		SPIClass *	theSPI = `&SPI`
	)

class constructor if using hardware SPI

Parameters

cspin	the chip select pin to use
*theSPI	optional SPI object

◆ Adafruit_BME280() [2/2]

Adafruit_BME280::Adafruit_BME280	(	int8_t	cspin,
		int8_t	mosipin,
		int8_t	misopin,
		int8_t	sckpin
	)

class constructor if using software SPI

Parameters

cspin	the chip select pin to use
mosipin	the MOSI pin to use
misopin	the MISO pin to use
sckpin	the SCK pin to use

Member Function Documentation

◆ begin()

bool Adafruit_BME280::begin	(	uint8_t	addr = `BME280_ADDRESS`,
		TwoWire *	theWire = `&Wire`
	)

Initialise sensor with given parameters / settings.

Parameters

addr	the I2C address the device can be found on
theWire	the I2C object to use, defaults to &Wire

Returns: true on success, false otherwise

◆ init()

bool Adafruit_BME280::init ( )

Initialise sensor with given parameters / settings.

Returns: true on success, false otherwise

◆ setSampling()

void Adafruit_BME280::setSampling	(	sensor_mode	mode = `MODE_NORMAL`,
		sensor_sampling	tempSampling = `SAMPLING_X16`,
		sensor_sampling	pressSampling = `SAMPLING_X16`,
		sensor_sampling	humSampling = `SAMPLING_X16`,
		sensor_filter	filter = `FILTER_OFF`,
		standby_duration	duration = `STANDBY_MS_0_5`
	)

setup sensor with given parameters / settings

Parameters

mode	the power mode to use for the sensor
tempSampling	the temp samping rate to use
pressSampling	the pressure sampling rate to use
humSampling	the humidity sampling rate to use
filter	the filter mode to use
duration	the standby duration to use

◆ takeForcedMeasurement()

bool Adafruit_BME280::takeForcedMeasurement ( void )

Take a new measurement (only possible in forced mode)

Returns: true in case of success else false

◆ readTemperature()

float Adafruit_BME280::readTemperature ( void )

Returns the temperature from the sensor.

Returns: the temperature read from the device or NaN if sampling off

◆ readPressure()

float Adafruit_BME280::readPressure ( void )

Returns the pressure from the sensor.

Returns: the pressure value (in Pascal) or NaN if sampling off

◆ readHumidity()

float Adafruit_BME280::readHumidity ( void )

Returns the humidity from the sensor.

Returns: the humidity value read from the device or NaN if sampling off

◆ readAltitude()

float Adafruit_BME280::readAltitude ( float seaLevel )

Calculates the altitude (in meters) from the specified atmospheric pressure (in hPa), and sea-level pressure (in hPa).

Parameters

seaLevel Sea-level pressure in hPa

Returns: the altitude value read from the device

◆ seaLevelForAltitude()

float Adafruit_BME280::seaLevelForAltitude	(	float	altitude,
		float	atmospheric
	)

Calculates the pressure at sea level (in hPa) from the specified altitude (in meters), and atmospheric pressure (in hPa).

Parameters

altitude	Altitude in meters
atmospheric	Atmospheric pressure in hPa

Returns: the pressure at sea level (in hPa) from the specified altitude

◆ sensorID()

uint32_t Adafruit_BME280::sensorID ( void )

Returns Sensor ID found by init() for diagnostics

Returns: Sensor ID 0x60 for BME280, 0x56, 0x57, 0x58 BMP280

◆ getTemperatureCompensation()

float Adafruit_BME280::getTemperatureCompensation ( void )

Returns the current temperature compensation value in degrees Celsius

Returns: the current temperature compensation value in degrees Celsius

◆ setTemperatureCompensation()

void Adafruit_BME280::setTemperatureCompensation ( float adjustment )

Sets a value to be added to each temperature reading. This adjusted temperature is used in pressure and humidity readings.

Parameters

adjustment Value to be added to each temperature reading in Celsius

◆ getTemperatureSensor()

Adafruit_Sensor * Adafruit_BME280::getTemperatureSensor ( void )

Gets an Adafruit Unified Sensor object for the temp sensor component.

Returns: Adafruit_Sensor pointer to temperature sensor

◆ getPressureSensor()

Adafruit_Sensor * Adafruit_BME280::getPressureSensor ( void )

Gets an Adafruit Unified Sensor object for the pressure sensor component.

Returns: Adafruit_Sensor pointer to pressure sensor

◆ getHumiditySensor()

Adafruit_Sensor * Adafruit_BME280::getHumiditySensor ( void )

Gets an Adafruit Unified Sensor object for the humidity sensor component.

Returns: Adafruit_Sensor pointer to humidity sensor

◆ isReadingCalibration()

bool Adafruit_BME280::isReadingCalibration ( void )

protected

return true if chip is busy reading cal data

Returns: true if reading calibration, false otherwise

◆ write8()

void Adafruit_BME280::write8	(	byte	reg,
		byte	value
	)

protected

Writes an 8 bit value over I2C or SPI.

Parameters

reg	the register address to write to
value	the value to write to the register

◆ read8()

uint8_t Adafruit_BME280::read8 ( byte reg )

protected

Reads an 8 bit value over I2C or SPI.

Parameters

reg	the register address to read from

Returns: the data byte read from the device

◆ read16()

uint16_t Adafruit_BME280::read16 ( byte reg )

protected

Reads a 16 bit value over I2C or SPI.

Parameters

reg	the register address to read from

Returns: the 16 bit data value read from the device

◆ read24()

uint32_t Adafruit_BME280::read24 ( byte reg )

protected

Reads a 24 bit value over I2C.

Parameters

reg	the register address to read from

Returns: the 24 bit data value read from the device

◆ readS16()

int16_t Adafruit_BME280::readS16 ( byte reg )

protected

Reads a signed 16 bit value over I2C or SPI.

Parameters

reg	the register address to read from

Returns: the 16 bit data value read from the device

◆ read16_LE()

uint16_t Adafruit_BME280::read16_LE ( byte reg )

protected

Reads a signed 16 bit little endian value over I2C or SPI.

Parameters

reg	the register address to read from

Returns: the 16 bit data value read from the device

◆ readS16_LE()

int16_t Adafruit_BME280::readS16_LE ( byte reg )

protected

Reads a signed little endian 16 bit value over I2C or SPI.

Parameters

reg	the register address to read from

Returns: the 16 bit data value read from the device

Member Data Documentation

◆ t_fine

int32_t Adafruit_BME280::t_fine

protected

temperature with high resolution, stored as an attribute as this is used for temperature compensation reading humidity and pressure

◆ t_fine_adjust

int32_t Adafruit_BME280::t_fine_adjust = 0

protected

add to compensate temp readings and in turn to pressure and humidity readings

The documentation for this class was generated from the following files:

Classes

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Adafruit_BME280() [1/2]

◆ Adafruit_BME280() [2/2]

Member Function Documentation

◆ begin()

◆ init()

◆ setSampling()

◆ takeForcedMeasurement()

◆ readTemperature()

◆ readPressure()

◆ readHumidity()

◆ readAltitude()

◆ seaLevelForAltitude()

◆ sensorID()

◆ getTemperatureCompensation()

◆ setTemperatureCompensation()

◆ getTemperatureSensor()

◆ getPressureSensor()

◆ getHumiditySensor()

◆ isReadingCalibration()

◆ write8()

◆ read8()

◆ read16()

◆ read24()

◆ readS16()

◆ read16_LE()

◆ readS16_LE()

Member Data Documentation

◆ t_fine

◆ t_fine_adjust