scd30_sensor.h File Reference

I²C driver for the SCD30 environmental sensor. More...

#include <stddef.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "rom/ets_sys.h"
#include "esp_err.h"
#include "i2c_bus.h"
#include "esp_log.h"

Go to the source code of this file.

Data Structures
struct	scd30_dev_t
	Structure representing the SCD30 device on an I²C bus. More...

Macros
#define	SCD30_I2C_ADDR   (0x61)
	Default I²C address for SCD30 sensors.

Typedefs
typedef uint16_t	p_mbar_t
	Type for pressure [mbar].
typedef uint16_t	i_sec_t
	Type for measurement interval [s].
typedef uint16_t	uco2_ppm_t
	Type for CO₂ concentration [ppm] (forced recalibration only).
typedef uint16_t	tx100_celsius_t
	Type for temperature [°C × 100].
typedef uint16_t	alt_m_t
	Type for altitude [m].
typedef float	t_celsius_t
	Type for temperature [°C].
typedef float	rh_percent_t
	Type for relative humidity [%].
typedef float	co2_ppm_t
	Type for CO₂ [ppm].
typedef uint8_t	i2c_addr_t
	Type for I²C addresses.
typedef void *	scd30_handle_t
	Opaque handle for an SCD30 sensor.

Functions
scd30_handle_t	scd30_i2c_create (i2c_bus_handle_t bus, i2c_addr_t dev_addr)
	Create a handle for an SCD30 sensor but does not apply any configuration.
scd30_handle_t	scd30_i2c_init (i2c_bus_handle_t bus, i2c_addr_t dev_addr)
	Initialize the SCD30 sensor on the I²C bus with a default configuration.
void	scd30_i2c_delete (scd30_handle_t sensor)
	Deinitialize the SCD30 sensor and free resources.
esp_err_t	scd30_i2c_trigger_continuous_measurement (scd30_handle_t sensor, p_mbar_t p_comp)
	Trigger continuous measurement.
esp_err_t	scd30_i2c_stop_continuous_measurement (scd30_handle_t sensor)
	Stop continuous measurement.
esp_err_t	scd30_i2c_read_measurement_interval (scd30_handle_t sensor, i_sec_t *interval)
	Read the measurement interval.
esp_err_t	scd30_i2c_write_measurement_interval (scd30_handle_t sensor, i_sec_t interval)
	Set measurement interval.
esp_err_t	scd30_i2c_read_data_ready_status (scd30_handle_t sensor, bool *data_ready)
	Check whether new measurement data is available for read-out.
esp_err_t	scd30_i2c_read_measurement (scd30_handle_t sensor, co2_ppm_t *co2, t_celsius_t *temperature, rh_percent_t *humidity)
	Read CO₂, temperature and humidity measurements.
esp_err_t	scd30_i2c_read_automatic_self_calibration (scd30_handle_t sensor, bool *enabled)
	Get automatic self calibration (ASC) state.
esp_err_t	scd30_i2c_write_automatic_self_calibration (scd30_handle_t sensor, bool enabled)
	Enable or disable automatic self calibration (ASC).
esp_err_t	scd30_i2c_read_forced_recalibration_value (scd30_handle_t sensor, uco2_ppm_t *frc)
	Get forced recalibration (FRC) value.
esp_err_t	scd30_i2c_write_forced_recalibration_value (scd30_handle_t sensor, uco2_ppm_t target)
	Set forced recalibration (FRC) value.
esp_err_t	scd30_i2c_read_temperature_offset_ticks (scd30_handle_t sensor, tx100_celsius_t *offset)
	Get temperature offset in ticks.
esp_err_t	scd30_i2c_read_temperature_offset (scd30_handle_t sensor, t_celsius_t *offset)
	Get temperature offset.
esp_err_t	scd30_i2c_write_temperature_offset_ticks (scd30_handle_t sensor, tx100_celsius_t offset)
	Set temperature offset in ticks.
esp_err_t	scd30_i2c_write_temperature_offset (scd30_handle_t sensor, t_celsius_t offset)
	Set temperature offset.
esp_err_t	scd30_i2c_read_sensor_altitude (scd30_handle_t sensor, alt_m_t *altitude)
	Get configured sensor altitude.
esp_err_t	scd30_i2c_write_sensor_altitude (scd30_handle_t sensor, alt_m_t altitude)
	Set sensor altitude above sea level.
esp_err_t	scd30_i2c_read_firmware_version (scd30_handle_t sensor, uint16_t *firmware_version)
	Get firmware version.
esp_err_t	scd30_i2c_soft_reset (scd30_handle_t sensor)
	Reset the sensor.

Detailed Description

I²C driver for the SCD30 environmental sensor.

Author

Adrien Chevrier

Copyright

• Portions under BSD-3-Clause license, derived from:
  • Copyright (c) 2021, Sensirion AG
  • Copyright (c) 2021, Ruslan V. Uss
  • Copyright (c) 2021, Nate Usher

• Modifications and rewrite for new I²C interface:
  • Copyright (c) 2026 Adrien Chevrier. Under AGPL-3.0-or-later license.

This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License along with this program. If not, see https://www.gnu.org/licenses/.

Version

0.1

Date

2026-02-04