Collaboration diagram for BME680:

Data Structures
struct	dev_bme680_data_t
	BME680 measurement values. More...

struct	dev_bme680_config_t
	BME680 runtime configuration. More...

Macros
#define	DEV_BME680_I2C_ADDR_PRIMARY 0x76
	7-bit I2C address when the SDO pin is tied low.

#define	DEV_BME680_I2C_ADDR_SECONDARY 0x77
	7-bit I2C address when the SDO pin is tied high.

#define	DEV_BME680_CHIP_ID 0x61
	Expected value of the chip ID register, used by dev_bme680_init() to confirm a BME680 is actually present before returning a handle.

#define	DEV_BME680_REG_CHIP_ID 0xD0u
	Register holding the chip ID (see DEV_BME680_CHIP_ID).

#define	DEV_BME680_REG_VARIANT_ID 0xF0u
	Register holding the chip variant (see DEV_BME680_VARIANT_GAS_LOW, DEV_BME680_VARIANT_GAS_HIGH).

#define	DEV_BME680_REG_SOFT_RESET 0xE0u
	Register that triggers a soft reset when DEV_BME680_SOFT_RESET_CMD is written to it.

#define	DEV_BME680_REG_FIELD0 0x1Du
	First register of the sensor data field read by dev_bme680_read().

#define	DEV_BME680_REG_RES_HEAT0 0x5Au
	First heater resistance register, for the gas heater profile.

#define	DEV_BME680_REG_GAS_WAIT0 0x64u
	First heater duration register, for the gas heater profile.

#define	DEV_BME680_REG_CTRL_GAS_0 0x70u
	Gas heater control register.

#define	DEV_BME680_REG_CTRL_GAS_1 0x71u
	Gas measurement/heater-profile-selection control register.

#define	DEV_BME680_REG_CTRL_HUM 0x72u
	Humidity oversampling control register.

#define	DEV_BME680_REG_CTRL_MEAS 0x74u
	Temperature/pressure oversampling and power-mode control register.

#define	DEV_BME680_REG_CONFIG 0x75u
	IIR filter control register.

#define	DEV_BME680_REG_COEFF1 0x8Au
	First byte of the first calibration coefficient block.

#define	DEV_BME680_REG_COEFF2 0xE1u
	First byte of the second calibration coefficient block.

#define	DEV_BME680_REG_COEFF3 0x00u
	First byte of the third calibration coefficient block.

#define	DEV_BME680_SOFT_RESET_CMD 0xB6u
	Value that triggers a soft reset when written to DEV_BME680_REG_SOFT_RESET.

#define	DEV_BME680_VARIANT_GAS_LOW 0x00u
	Chip variant value read from DEV_BME680_REG_VARIANT_ID on earlier BME680 units, using the "low" gas resistance compensation formula.

#define	DEV_BME680_VARIANT_GAS_HIGH 0x01u
	Chip variant value read from DEV_BME680_REG_VARIANT_ID on later BME680 units, using the "high" gas resistance compensation formula.

Typedefs
typedef struct dev_bme680_t	dev_bme680_t
	Opaque BME680 handle.

Lifecycle
void	dev_bme680_default_config (dev_bme680_config_t *config)
	Fill a BME680 config struct with safe defaults. More...

dev_bme680_t *	dev_bme680_init (hw_deviceio_t device, const dev_bme680_config_t config)
	Initialize a BME680 sensor. More...

void	dev_bme680_deinit (dev_bme680_t *bme680)
	Deinitialize a BME680 sensor. More...

Properties
uint8_t	dev_bme680_chip_id (const dev_bme680_t *bme680)
	Get the detected chip ID. More...

uint32_t	dev_bme680_measurement_duration_ms (const dev_bme680_config_t *config)
	Calculate how long a measurement takes to complete for a given configuration. More...

Methods
bool	dev_bme680_read (dev_bme680_t bme680, dev_bme680_data_t data)
	Read sensor data from BME680. More...

Detailed Description

Function Documentation

◆ dev_bme680_chip_id()

uint8_t dev_bme680_chip_id ( const dev_bme680_t * bme680 )

Get the detected chip ID.

Parameters

bme680 BME680 handle.

Returns: Chip ID, or 0 when handle is invalid.

◆ dev_bme680_default_config()

void dev_bme680_default_config ( dev_bme680_config_t * config )

Fill a BME680 config struct with safe defaults.

Parameters

config Config structure to initialize.

◆ dev_bme680_deinit()

void dev_bme680_deinit ( dev_bme680_t * bme680 )

Deinitialize a BME680 sensor.

Parameters

bme680 BME680 handle.

Releases bme680 itself only - the hw_deviceio_t it was initialized with is left open, since dev_bme680_init() doesn't take ownership of it.

◆ dev_bme680_init()

dev_bme680_t* dev_bme680_init	(	hw_deviceio_t *	device,
		const dev_bme680_config_t *	config
	)

Initialize a BME680 sensor.

Parameters

device	Device I/O handle to communicate over, from hw_i2c_init() or hw_spi_init() (see hw/i2c.h, hw/spi.h).
config	Optional configuration. Pass NULL for defaults.

Returns: BME680 handle, or NULL on failure. Release it with dev_bme680_deinit().

◆ dev_bme680_measurement_duration_ms()

uint32_t dev_bme680_measurement_duration_ms ( const dev_bme680_config_t * config )

Calculate how long a measurement takes to complete for a given configuration.

Parameters

config Configuration to calculate for. Pass NULL to use defaults.

Returns: Expected measurement duration in milliseconds.

Oversampling settings determine the temperature/pressure/humidity conversion time; when config->gas_mode is dev_bme680_gas_enabled, config->heater_duration_ms is added on top, since the gas heater and the TPH conversion don't run concurrently. dev_bme680_read() already accounts for this internally when polling for a result - this is for a caller that wants to know the figure itself (e.g. to pick a sensible polling interval elsewhere).

◆ dev_bme680_read()

bool dev_bme680_read	(	dev_bme680_t *	bme680,
		dev_bme680_data_t *	data
	)

Read sensor data from BME680.

Parameters

bme680	BME680 handle.
data	Structure to receive sensor values.

Return values

true	Read succeeded.
false	Read failed.

picofuse

Data Structures

Macros

Typedefs

Lifecycle

Properties

Methods

Detailed Description

Function Documentation

◆ dev_bme680_chip_id()

◆ dev_bme680_default_config()

◆ dev_bme680_deinit()

◆ dev_bme680_init()

◆ dev_bme680_measurement_duration_ms()

◆ dev_bme680_read()