unit_SHT40.hpp

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/*
 * SPDX-FileCopyrightText: 2024 M5Stack Technology CO LTD
 *
 * SPDX-License-Identifier: MIT
 */
#ifndef M5_UNIT_ENV_UNIT_SHT40_HPP
#define M5_UNIT_ENV_UNIT_SHT40_HPP
 
#include <M5UnitComponent.hpp>
#include <m5_utility/container/circular_buffer.hpp>
#include <limits>  // NaN
 
namespace m5 {
namespace unit {
 
namespace sht40 {
 
enum class Precision : uint8_t {
    High,    
    Medium,  
    Low      
};
 
enum class Heater : uint8_t {
    Long,   
    Short,  
    None    
};
 
struct Data {
    std::array<uint8_t, 6> raw{};  
    bool heater{};                 
 
    inline float temperature() const
    {
        return celsius();
    }
    float celsius() const;     
    float fahrenheit() const;  
    float humidity() const;    
};
 
}  // namespace sht40
 
class UnitSHT40 : public Component, public PeriodicMeasurementAdapter<UnitSHT40, sht40::Data> {
    M5_UNIT_COMPONENT_HPP_BUILDER(UnitSHT40, 0x44);
 
public:
    struct config_t {
        bool start_periodic{true};
        sht40::Precision precision{sht40::Precision::High};
        sht40::Heater heater{sht40::Heater::None};
        float heater_duty{0.05f};
    };
 
    explicit UnitSHT40(const uint8_t addr = DEFAULT_ADDRESS)
        : Component(addr), _data{new m5::container::CircularBuffer<sht40::Data>(1)}
    {
        auto ccfg  = component_config();
        ccfg.clock = 400 * 1000U;
        component_config(ccfg);
    }
    virtual ~UnitSHT40()
    {
    }
 
    virtual bool begin() override;
    virtual void update(const bool force = false) override;
 
 
    inline config_t config()
    {
        return _cfg;
    }
    inline void config(const config_t& cfg)
    {
        _cfg = cfg;
    }
 
    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 sht40::Precision precision, const sht40::Heater heater,
                                         const float duty = 0.05f)
    {
        return PeriodicMeasurementAdapter<UnitSHT40, sht40::Data>::startPeriodicMeasurement(precision, heater, duty);
    }
    inline bool stopPeriodicMeasurement()
    {
        return PeriodicMeasurementAdapter<UnitSHT40, sht40::Data>::stopPeriodicMeasurement();
    }
 
 
    bool measureSingleshot(sht40::Data& d, const sht40::Precision precision = sht40::Precision::High,
                           const sht40::Heater heater = sht40::Heater::None);
 
 
 
    bool softReset();
    bool generalReset();
 
 
    bool readSerialNumber(uint32_t& serialNumber);
    bool readSerialNumber(char* serialNumber);
 
protected:
    bool start_periodic_measurement(const sht40::Precision precision, const sht40::Heater heater, const float duty);
    bool stop_periodic_measurement();
    bool read_measurement(sht40::Data& d);
    void reset_status();
    bool soft_reset();
 
    M5_UNIT_COMPONENT_PERIODIC_MEASUREMENT_ADAPTER_HPP_BUILDER(UnitSHT40, sht40::Data);
 
protected:
    std::unique_ptr<m5::container::CircularBuffer<sht40::Data>> _data{};
    config_t _cfg{};
    uint8_t _cmd{}, _measureCmd{};
    types::elapsed_time_t _latest_heater{}, _interval_heater{};
    uint32_t _duration_measure{}, _duration_heater{};
};
 
namespace sht40 {
namespace command {
constexpr uint8_t MEASURE_HIGH_HEATER_1S{0x39};
constexpr uint8_t MEASURE_HIGH_HEATER_100MS{0x32};
constexpr uint8_t MEASURE_HIGH{0xFD};
 
constexpr uint8_t MEASURE_MEDIUM_HEATER_1S{0x2F};
constexpr uint8_t MEASURE_MEDIUM_HEATER_100MS{0x24};
constexpr uint8_t MEASURE_MEDIUM{0xF6};
 
constexpr uint8_t MEASURE_LOW_HEATER_1S{0x1E};
constexpr uint8_t MEASURE_LOW_HEATER_100MS{0x15};
constexpr uint8_t MEASURE_LOW{0xE0};
 
constexpr uint8_t GET_SERIAL_NUMBER{0x89};
constexpr uint8_t SOFT_RESET{0x94};
}  // namespace command
}  // namespace sht40
}  // namespace unit
}  // namespace m5
#endif