BME280 Sensor

Macros
#define	BME280_I2C_ADDR   (0x77)
	Default I²C address for BME280 sensors.

Typedefs
typedef uint8_t	i2c_addr_t
	Type for I²C addresses.
typedef float	t_celsius_t
	Type for temperature [°C].
typedef float	rh_percent_t
	Type for relative humidity [%].
typedef float	p_hpa_t
	Type for atmospheric pressure [hPa].

Functions
bme280_handle_t	bme280_i2c_init (i2c_bus_handle_t bus, i2c_addr_t i2c_addr)
	Initialize a BME280 sensor on the specified I2C bus.
esp_err_t	bme280_i2c_read_measurement (bme280_handle_t sensor, t_celsius_t *t, rh_percent_t *h, p_hpa_t *p)
	Read temperature, humidity, and pressure from a BME280 sensor.
void	bme280_i2c_delete (bme280_handle_t sensor)
	Deinitialize a BME280 sensor and free associated resources.

Detailed Description

Copyright

Copyright (c) 2026 Adrien Chevrier. Under AGPL-3.0-or-later license.

ESP-IDF I²C interface for the Bosch BME280 environmental sensor.

This interface uses the driver provided at https://github.com/espressif/esp-iot-solution/tree/1f4206cfe0ff480fedd4fa7860dc41ece6768812/components/sensors/pressure/bme280

Macro Definition Documentation

BME280_I2C_ADDR

#define BME280_I2C_ADDR   (0x77)

Default I²C address for BME280 sensors.

Typedef Documentation

i2c_addr_t

typedef uint8_t i2c_addr_t

Type for I²C addresses.

p_hpa_t

typedef float p_hpa_t

Type for atmospheric pressure [hPa].

rh_percent_t

typedef float rh_percent_t

Type for relative humidity [%].

t_celsius_t

typedef float t_celsius_t

Type for temperature [°C].

Function Documentation

bme280_i2c_delete()

void bme280_i2c_delete

(

bme280_handle_t

sensor

)

Deinitialize a BME280 sensor and free associated resources.

Parameters

[in,out]

sensor

The sensor handle returned by bme280_i2c_init().

Warning

This function must run inside a critical section.

bme280_i2c_init()

bme280_handle_t bme280_i2c_init	(	i2c_bus_handle_t	bus,
		i2c_addr_t	i2c_addr )

Initialize a BME280 sensor on the specified I2C bus.

Parameters

[in]	bus	The I²C bus handle to use.
[in]	i2c_addr	The I²C address of the sensor.

Return values

bme280_handle_t	Handle to the initialized BME280 sensor.
NULL	On failure.

Note

The returned handle must be freed with bme280_i2c_delete()

Warning

This function must run inside a critical section.

bme280_i2c_read_measurement()

esp_err_t bme280_i2c_read_measurement	(	bme280_handle_t	sensor,
		t_celsius_t *	t,
		rh_percent_t *	h,
		p_hpa_t *	p )

Read temperature, humidity, and pressure from a BME280 sensor.

Parameters

[in]	sensor	The sensor handle returned by bme280_i2c_init() .
[out]	t	Pointer to a variable to receive temperature.
[out]	h	Pointer to a variable to receive relative humidity.
[out]	p	Pointer to a variable to receive atmospheric pressure.

Return values

ESP_OK	On success.
ESP_ERR_INVALID_ARG	If any parameter is NULL.
ESP_FAIL	If the sensor read fails.