1 /* 2 * Copyright (c) 2024 Jan Fäh 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 #ifndef ZEPHYR_INCLUDE_DRIVERS_SENSOR_SCD4X_H_ 8 #define ZEPHYR_INCLUDE_DRIVERS_SENSOR_SCD4X_H_ 9 10 #include <zephyr/drivers/sensor.h> 11 12 enum sensor_attribute_scd4x { 13 /* Offset temperature: Toffset_actual = Tscd4x – Treference + Toffset_previous 14 * 0 - 20°C 15 */ 16 SENSOR_ATTR_SCD4X_TEMPERATURE_OFFSET = SENSOR_ATTR_PRIV_START, 17 /* Altidude of the sensor; 18 * 0 - 3000m 19 */ 20 SENSOR_ATTR_SCD4X_SENSOR_ALTITUDE, 21 /* Ambient pressure in hPa 22 * 700 - 1200hPa 23 */ 24 SENSOR_ATTR_SCD4X_AMBIENT_PRESSURE, 25 /* Set the current state (enabled: 1 / disabled: 0). 26 * Default: enabled. 27 */ 28 SENSOR_ATTR_SCD4X_AUTOMATIC_CALIB_ENABLE, 29 /* Set the initial period for automatic self calibration correction in hours. Allowed values 30 * are integer multiples of 4 hours. 31 * Default: 44 32 */ 33 SENSOR_ATTR_SCD4X_SELF_CALIB_INITIAL_PERIOD, 34 /* Set the standard period for automatic self calibration correction in hours. Allowed 35 * values are integer multiples of 4 hours. Default: 156 36 */ 37 SENSOR_ATTR_SCD4X_SELF_CALIB_STANDARD_PERIOD, 38 }; 39 40 /** 41 * @brief Performs a forced recalibration. 42 * 43 * Operate the SCD4x in the operation mode for at least 3 minutes in an environment with a 44 * homogeneous and constant CO2 concentration. Otherwise the recalibratioin will fail. The sensor 45 * must be operated at the voltage desired for the application when performing the FRC sequence. 46 * 47 * @param dev Pointer to the sensor device 48 * @param target_concentration Reference CO2 concentration. 49 * @param frc_correction Previous differences from the target concentration 50 * 51 * @return 0 if successful, negative errno code if failure. 52 */ 53 int scd4x_forced_recalibration(const struct device *dev, uint16_t target_concentration, 54 uint16_t *frc_correction); 55 56 /** 57 * @brief Performs a self test. 58 * 59 * The self_test command can be used as an end-of-line test to check the sensor functionality 60 * 61 * @param dev Pointer to the sensor device 62 * 63 * @return 0 if successful, negative errno code if failure. 64 */ 65 int scd4x_self_test(const struct device *dev); 66 67 /** 68 * @brief Performs a self test. 69 * 70 * The persist_settings command can be used to save the actual configuration. This command 71 * should only be sent when persistence is required and if actual changes to the configuration have 72 * been made. The EEPROM is guaranteed to withstand at least 2000 write cycles 73 * 74 * @param dev Pointer to the sensor device 75 * 76 * @return 0 if successful, negative errno code if failure. 77 */ 78 int scd4x_persist_settings(const struct device *dev); 79 80 /** 81 * @brief Performs a factory reset. 82 * 83 * The perform_factory_reset command resets all configuration settings stored in the EEPROM and 84 * erases the FRC and ASC algorithm history. 85 * 86 * @param dev Pointer to the sensor device 87 * 88 * @return 0 if successful, negative errno code if failure. 89 */ 90 int scd4x_factory_reset(const struct device *dev); 91 92 #endif /* ZEPHYR_INCLUDE_DRIVERS_SENSOR_SCD4X_H_ */ 93
