API for the BME280 Digital Humidity, Pressure, and Temperature Sensor. More...

Detailed Description

ID: bme280
Name: Digital Humidity, Pressure, and Temperature Sensor
Category: pressure humidity
Manufacturer: bosch adafruit
Connection: i2c spi gpio
Link: https://www.adafruit.com/products/2652

The BME280 is as combined digital humidity, pressure and temperature sensor based on proven sensing principles. The sensor module is housed in an extremely compact metal-lid LGA package with a footprint of only 2.5 * 2.5 mm2 with a height of 0.93 mm. Its small dimensions and its low power consumption allow the implementation in battery driven devices such as handsets, GPS modules or watches. The BME280 is register and performance compatible to the Bosch Sensortec BMP280 digital pressure sensor.

    // Instantiate a BME280 instance using default i2c bus and address
    upm::BME280 sensor;
    // For SPI, bus 0, you would pass -1 as the address, and a valid pin for CS:
    // BME280(0, -1, 10);
    while (shouldRun) {
        // update our values from the sensor
        sensor.update();
        // we show both C and F for temperature
        cout << "Compensation Temperature: " << sensor.getTemperature() << " C / "
             << sensor.getTemperature(true) << " F" << endl;
        cout << "Pressure: " << sensor.getPressure() << " Pa" << endl;
        cout << "Computed Altitude: " << sensor.getAltitude() << " m" << endl;
        cout << "Humidity: " << sensor.getHumidity() << " %RH" << endl;
        cout << endl;
        upm_delay(1);
    }

Public Member Functions
	BME280 (int bus=BME280_DEFAULT_I2C_BUS, int addr=BME280_DEFAULT_ADDR, int cs=-1)

virtual	~BME280 ()

float	getHumidity ()

void	setOversampleRateHumidity (BME280_OSRS_H_T rate)

const char *	getModuleName ()

int	getHumidityRelative ()

Public Member Functions inherited from BMP280
	BMP280 (int bus=BMP280_DEFAULT_I2C_BUS, int addr=BMP280_DEFAULT_ADDR, int cs=-1)

virtual	~BMP280 ()

virtual void	update ()

uint8_t	getChipID ()

void	reset ()

float	getTemperature (bool fahrenheit=false)

float	getPressure ()

void	setSeaLevelPreassure (float seaLevelhPA=1013.25)

float	getAltitude ()

virtual void	setUsageMode (BMP280_USAGE_MODE_T mode)

void	setOversampleRateTemperature (BMP280_OSRS_T_T rate)

void	setOversampleRatePressure (BMP280_OSRS_P_T rate)

void	setTimerStandby (BMP280_T_SB_T tsb)

void	setFilter (BMP280_FILTER_T filter)

void	setMeasureMode (BMP280_MODES_T mode)

const char *	getModuleName ()

int	getTemperatureCelsius ()

int	getPressurePa ()

Additional Inherited Members
Protected Member Functions inherited from BMP280
uint8_t	getStatus ()

uint8_t	readReg (uint8_t reg)

int	readRegs (uint8_t reg, uint8_t *buffer, int len)

void	writeReg (uint8_t reg, uint8_t val)

Protected Attributes inherited from BMP280
bmp280_context	m_bmp280

Constructor & Destructor Documentation

BME280	(	int	bus = `BME280_DEFAULT_I2C_BUS`,
		int	addr = `BME280_DEFAULT_ADDR`,
		int	cs = `-1`
	)

BME280 constructor.

This driver supports both the BMP280 and the BME280. The BME280 adds a humidity sensor. The device type is detected automatically by querying the chip id register.

This device can support both I2C and SPI. For SPI, set the addr to -1, and specify a positive integer representing the Chip Select (CS) pin for the cs argument. If you are using a hardware CS pin, then you can connect the proper pin to the hardware CS pin on your MCU and supply -1 for cs. The default operating mode is I2C.

Parameters

bus	I2C or SPI bus to use.
addr	The I2C address for this device. Use -1 for SPI.
cs	The gpio pin to use for the SPI Chip Select. Use -1 for I2C, or for SPI with a hardware controlled pin.

Exceptions

std::runtime_error on failure.

~BME280 ( )

virtual

BME280 Destructor.

Member Function Documentation

float getHumidity ( void )

Return the current measured relative humidity. update() must have been called prior to calling this method. If the device is a bmp280 rather than a bme280, this method will always return 0.

Returns: The relative humidity in percent.

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void setOversampleRateHumidity ( BME280_OSRS_H_T rate )

Set the humidity sensor oversampling parameter. See the data sheet for details. This value can be automatically set to a suitable value by using one of the predefined modes for setUsageMode().

Parameters