unit_SCD40.hpp

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/*
 * SPDX-FileCopyrightText: 2024 M5Stack Technology CO LTD
 *
 * SPDX-License-Identifier: MIT
 */
#ifndef M5_UNIT_ENV_UNIT_SCD40_HPP
#define M5_UNIT_ENV_UNIT_SCD40_HPP
 
#include <M5UnitComponent.hpp>
#include <m5_utility/container/circular_buffer.hpp>
#include <limits>  // NaN
 
namespace m5 {
namespace unit {
 
namespace scd4x {
enum class Mode : uint8_t {
    Normal,    
    LowPower,  
};
 
struct Data {
    std::array<uint8_t, 9> raw{};  
    uint16_t co2() const;          
    inline float temperature() const
    {
        return celsius();
    }
    float celsius() const;     
    float fahrenheit() const;  
    float humidity() const;    
};
 
// Max command duration(ms)
// For SCD40/41
constexpr uint16_t READ_MEASUREMENT_DURATION{1};
constexpr uint16_t STOP_PERIODIC_MEASUREMENT_DURATION{500};
constexpr uint16_t SET_TEMPERATURE_OFFSET_DURATION{1};
constexpr uint16_t GET_TEMPERATURE_OFFSET_DURATION{1};
constexpr uint16_t SET_SENSOR_ALTITUDE_DURATION{1};
constexpr uint16_t GET_SENSOR_ALTITUDE_DURATION{1};
constexpr uint16_t SET_AMBIENT_PRESSURE_DURATION{1};
constexpr uint16_t GET_AMBIENT_PRESSURE_DURATION{1};
constexpr uint16_t PERFORM_FORCED_CALIBRATION_DURATION{400};
constexpr uint16_t SET_AUTOMATIC_SELF_CALIBRATION_ENABLED_DURATION{1};
constexpr uint16_t GET_AUTOMATIC_SELF_CALIBRATION_ENABLED_DURATION{1};
constexpr uint16_t SET_AUTOMATIC_SELF_CALIBRATION_TARGET_DURATION{1};
constexpr uint16_t GET_AUTOMATIC_SELF_CALIBRATION_TARGET_DURATION{1};
constexpr uint16_t GET_DATA_READY_STATUS_DURATION{1};
constexpr uint16_t PERSIST_SETTINGS_DURATION{800};
constexpr uint16_t GET_SERIAL_NUMBER_DURATION{1};
constexpr uint16_t PERFORM_SELF_TEST_DURATION{10000};
constexpr uint16_t PERFORM_FACTORY_RESET_DURATION{1200};
constexpr uint16_t REINIT_DURATION{20};
 
}  // namespace scd4x
 
class UnitSCD40 : public Component, public PeriodicMeasurementAdapter<UnitSCD40, scd4x::Data> {
    M5_UNIT_COMPONENT_HPP_BUILDER(UnitSCD40, 0x62);
 
public:
    struct config_t {
        bool start_periodic{true};
        scd4x::Mode mode{scd4x::Mode::Normal};
        bool calibration{true};
    };
 
    explicit UnitSCD40(const uint8_t addr = DEFAULT_ADDRESS)
        : Component(addr), _data{new m5::container::CircularBuffer<scd4x::Data>(1)}
    {
        auto ccfg  = component_config();
        ccfg.clock = 400 * 1000U;
        component_config(ccfg);
    }
    virtual ~UnitSCD40()
    {
    }
 
    virtual bool begin() override;
    virtual void update(const bool force = false) override;
 
 
    inline config_t config() const
    {
        return _cfg;
    }
    inline void config(const config_t &cfg)
    {
        _cfg = cfg;
    }
 
    inline uint16_t co2() const
    {
        return !empty() ? oldest().co2() : 0;
    }
    inline float temperature() const
    {
        return !empty() ? oldest().temperature() : std::numeric_limits<float>::quiet_NaN();
    }
    inline float celsius() const
    {
        return !empty() ? oldest().celsius() : std::numeric_limits<float>::quiet_NaN();
    }
    inline float fahrenheit() const
    {
        return !empty() ? oldest().fahrenheit() : std::numeric_limits<float>::quiet_NaN();
    }
    inline float humidity() const
    {
        return !empty() ? oldest().humidity() : std::numeric_limits<float>::quiet_NaN();
    }
 
 
    inline bool startPeriodicMeasurement(const scd4x::Mode mode = scd4x::Mode::Normal)
    {
        return PeriodicMeasurementAdapter<UnitSCD40, scd4x::Data>::startPeriodicMeasurement(mode);
    }
    inline bool startLowPowerPeriodicMeasurement()
    {
        return startPeriodicMeasurement(scd4x::Mode::LowPower);
    }
    inline bool stopPeriodicMeasurement(const uint32_t duration = scd4x::STOP_PERIODIC_MEASUREMENT_DURATION)
    {
        return PeriodicMeasurementAdapter<UnitSCD40, scd4x::Data>::stopPeriodicMeasurement(duration);
    }
 
 
    bool writeTemperatureOffset(const float offset, const uint32_t duration = scd4x::SET_TEMPERATURE_OFFSET_DURATION);
    bool readTemperatureOffset(float &offset);
    bool writeSensorAltitude(const uint16_t altitude, const uint32_t duration = scd4x::SET_SENSOR_ALTITUDE_DURATION);
    bool readSensorAltitude(uint16_t &altitude);
    bool writeAmbientPressure(const uint16_t pressure, const uint32_t duration = scd4x::SET_AMBIENT_PRESSURE_DURATION);
    bool readAmbientPressure(uint16_t &pressure);
 
 
    bool performForcedRecalibration(const uint16_t concentration, int16_t &correction);
    bool writeAutomaticSelfCalibrationEnabled(
        const bool enabled = true, const uint32_t duration = scd4x::SET_AUTOMATIC_SELF_CALIBRATION_ENABLED_DURATION);
    bool readAutomaticSelfCalibrationEnabled(bool &enabled);
 
    bool writeAutomaticSelfCalibrationTarget(
        const uint16_t ppm, const uint32_t duration = scd4x::SET_AUTOMATIC_SELF_CALIBRATION_TARGET_DURATION);
    bool readAutomaticSelfCalibrationTarget(uint16_t &ppm);
 
 
    bool writePersistSettings(const uint32_t duration = scd4x::PERSIST_SETTINGS_DURATION);
    bool readSerialNumber(char *serialNumber);
    bool readSerialNumber(uint64_t &serialNumber);
    bool performSelfTest(bool &malfunction);
    bool performFactoryReset(const uint32_t duration = scd4x::PERFORM_FACTORY_RESET_DURATION);
    bool reInit(const uint32_t duration = scd4x::REINIT_DURATION);
 
protected:
    bool read_register(const uint16_t reg, uint8_t *rbuf, const uint32_t rlen, const uint32_t duration = 1);
    bool write_register(const uint16_t reg, uint8_t *wbuf, const uint32_t wlen);
 
    bool start_periodic_measurement(const scd4x::Mode mode = scd4x::Mode::Normal);
    bool stop_periodic_measurement(const uint32_t duration = scd4x::STOP_PERIODIC_MEASUREMENT_DURATION);
    bool read_data_ready_status();
    bool read_measurement(scd4x::Data &d, const bool all = true);
 
    virtual bool is_valid_chip();
    bool delay_true(const uint32_t duration);
 
    M5_UNIT_COMPONENT_PERIODIC_MEASUREMENT_ADAPTER_HPP_BUILDER(UnitSCD40, scd4x::Data);
 
protected:
    std::unique_ptr<m5::container::CircularBuffer<scd4x::Data>> _data{};
    config_t _cfg{};
};
 
namespace scd4x {
namespace command {
// Basic Commands
constexpr uint16_t START_PERIODIC_MEASUREMENT{0x21b1};
constexpr uint16_t READ_MEASUREMENT{0xec05};
constexpr uint16_t STOP_PERIODIC_MEASUREMENT{0x3f86};
// On-chip output signal compensation
constexpr uint16_t SET_TEMPERATURE_OFFSET{0x241d};
constexpr uint16_t GET_TEMPERATURE_OFFSET{0x2318};
constexpr uint16_t SET_SENSOR_ALTITUDE{0x2427};
constexpr uint16_t GET_SENSOR_ALTITUDE{0x2322};
constexpr uint16_t AMBIENT_PRESSURE{0xe000};
// Field calibration
constexpr uint16_t PERFORM_FORCED_CALIBRATION{0x362f};
constexpr uint16_t SET_AUTOMATIC_SELF_CALIBRATION_ENABLED{0x2416};
constexpr uint16_t GET_AUTOMATIC_SELF_CALIBRATION_ENABLED{0x2313};
constexpr uint16_t SET_AUTOMATIC_SELF_CALIBRATION_TARGET{0x243a};
constexpr uint16_t GET_AUTOMATIC_SELF_CALIBRATION_TARGET{0x233f};
// Low power
constexpr uint16_t START_LOW_POWER_PERIODIC_MEASUREMENT{0x21ac};
constexpr uint16_t GET_DATA_READY_STATUS{0xe4b8};
// Advanced features
constexpr uint16_t PERSIST_SETTINGS{0x3615};
constexpr uint16_t GET_SERIAL_NUMBER{0x3682};
constexpr uint16_t PERFORM_SELF_TEST{0x3639};
constexpr uint16_t PERFORM_FACTORY_RESET{0x3632};
constexpr uint16_t REINIT{0x3646};
//
constexpr uint16_t GET_SENSOR_VARIANT{0x202f};
}  // namespace command
}  // namespace scd4x
 
}  // namespace unit
}  // namespace m5
#endif