unit_KmeterISO.hpp

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/*
 * SPDX-FileCopyrightText: 2024 M5Stack Technology CO LTD
 *
 * SPDX-License-Identifier: MIT
 */
#ifndef M5_UNIT_METER_UNIT_KMETERISO_HPP
#define M5_UNIT_METER_UNIT_KMETERISO_HPP
 
#include <M5UnitComponent.hpp>
#include <m5_utility/container/circular_buffer.hpp>
#include <limits>  // NaN
#include <array>
 
namespace m5 {
namespace unit {
 
namespace kmeter_iso {
 
enum class MeasurementUnit : uint8_t {
    Celsius,     
    Fahrenheit,  
};
 
struct Data {
    std::array<uint8_t, 4> raw{};  
 
    inline float temperature() const
    {
        return static_cast<int32_t>((static_cast<uint32_t>(raw[3]) << 24) | (static_cast<uint32_t>(raw[2]) << 16) |
                                    (static_cast<uint32_t>(raw[1]) << 8) | static_cast<uint32_t>(raw[0])) *
               0.01f;
    }
};
}  // namespace kmeter_iso
 
class UnitKmeterISO : public Component, public PeriodicMeasurementAdapter<UnitKmeterISO, kmeter_iso::Data> {
    M5_UNIT_COMPONENT_HPP_BUILDER(UnitKmeterISO, 0x66);
 
public:
    struct config_t {
        bool start_periodic{true};
        uint32_t interval{100};
        kmeter_iso::MeasurementUnit measurement_unit{kmeter_iso::MeasurementUnit::Celsius};
    };
 
    explicit UnitKmeterISO(const uint8_t addr = DEFAULT_ADDRESS)
        : Component(addr), _data{new m5::container::CircularBuffer<kmeter_iso::Data>(1)}
    {
        // 100 kHz: the firmware's slave data setup time (STM32F030, I2CCLK 8 MHz) does not meet the Fast-mode worst
        // case (RM0360 22.4.5), and the official driver also uses 100 kHz
        auto ccfg  = component_config();
        ccfg.clock = 100 * 1000U;
        component_config(ccfg);
    }
    virtual ~UnitKmeterISO()
    {
    }
 
    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;
    }
 
    kmeter_iso::MeasurementUnit measurementUnit() const
    {
        return _munit;
    }
    void setMeasurementUnit(const kmeter_iso::MeasurementUnit munit)
    {
        _munit = munit;
    }
 
    inline float temperature() const
    {
        return !empty() ? oldest().temperature() : std::numeric_limits<float>::quiet_NaN();
    }
 
 
    inline bool startPeriodicMeasurement()
    {
        return PeriodicMeasurementAdapter<UnitKmeterISO, kmeter_iso::Data>::startPeriodicMeasurement();
    }
    inline bool startPeriodicMeasurement(const uint32_t interval,
                                         const kmeter_iso::MeasurementUnit munit = kmeter_iso::MeasurementUnit::Celsius)
    {
        return PeriodicMeasurementAdapter<UnitKmeterISO, kmeter_iso::Data>::startPeriodicMeasurement(interval, munit);
    }
    inline bool stopPeriodicMeasurement()
    {
        return PeriodicMeasurementAdapter<UnitKmeterISO, kmeter_iso::Data>::stopPeriodicMeasurement();
    }
 
    bool readStatus(uint8_t& status);
 
    bool readFirmwareVersion(uint8_t& ver);
 
 
    bool measureSingleshot(kmeter_iso::Data& data,
                           const kmeter_iso::MeasurementUnit munit = kmeter_iso::MeasurementUnit::Celsius,
                           const uint32_t timeoutMs                = 100);
    bool measureInternalSingleshot(kmeter_iso::Data& data,
                                   const kmeter_iso::MeasurementUnit munit = kmeter_iso::MeasurementUnit::Celsius,
                                   const uint32_t timeoutMs                = 100);
 
 
    bool changeI2CAddress(const uint8_t i2c_address);
    bool readI2CAddress(uint8_t& i2c_address);
 
protected:
    bool start_periodic_measurement();
    bool start_periodic_measurement(const uint32_t interval, const kmeter_iso::MeasurementUnit munit);
    bool stop_periodic_measurement();
 
    bool read_measurement(kmeter_iso::Data& d, const kmeter_iso::MeasurementUnit munit);
    bool read_internal_measurement(kmeter_iso::Data& d, const kmeter_iso::MeasurementUnit munit);
 
    bool is_data_ready()
    {
        uint8_t s{};
        return readStatus(s) && (s == 0U);
    }
    M5_UNIT_COMPONENT_PERIODIC_MEASUREMENT_ADAPTER_HPP_BUILDER(UnitKmeterISO, kmeter_iso::Data);
 
protected:
    std::unique_ptr<m5::container::CircularBuffer<kmeter_iso::Data>> _data{};
    kmeter_iso::MeasurementUnit _munit{kmeter_iso::MeasurementUnit::Celsius};
    config_t _cfg{};
};
 
namespace kmeter_iso {
namespace command {
// See also https://github.com/m5stack/M5Unit-KMeterISO/blob/main/docs/Unit_KmeterISO_I2C_Protocol.pdf
constexpr uint8_t TEMPERATURE_CELSIUS_REG{0X00};
constexpr uint8_t TEMPERATURE_FAHRENHEIT_REG{0X04};
constexpr uint8_t INTERNAL_TEMPERATURE_CELSIUS_REG{0X10};
constexpr uint8_t INTERNAL_TEMPERATURE_FAHRENHEIT_REG{0X14};
constexpr uint8_t STATUS_REG{0x20};
constexpr uint8_t TEMPERATURE_CELSIUS_STRING_REG{0x30};
constexpr uint8_t TEMPERATURE_FAHRENHEIT_STRING_REG{0x40};
constexpr uint8_t INTERNAL_TEMPERATURE_CELSIUS_STRING_REG{0x50};
constexpr uint8_t INTERNAL_TEMPERATURE_FAHRENHEIT_STRING_REG{0x60};
constexpr uint8_t FIRMWARE_VERSION_REG{0xFE};
constexpr uint8_t I2C_ADDRESS_REG{0xFF};
}  // namespace command
}  // namespace kmeter_iso
 
}  // namespace unit
}  // namespace m5
#endif