unit_Thermal2_data.hpp

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/*
 * SPDX-FileCopyrightText: 2025 M5Stack Technology CO LTD
 *
 * SPDX-License-Identifier: MIT
 */
#ifndef M5_UNIT_THERMO_UNIT_THERMAL2_DATA_HPP
#define M5_UNIT_THERMO_UNIT_THERMAL2_DATA_HPP
 
#include <algorithm>
#include <cmath>
#include <cstdint>
#include <limits>  // NaN
 
namespace m5 {
namespace unit {
 
namespace thermal2 {
 
constexpr uint8_t button_is_pressed{0x01};    
constexpr uint8_t button_was_pressed{0x02};   
constexpr uint8_t button_was_released{0x04};  
constexpr uint8_t button_was_clicked{0x08};   
constexpr uint8_t button_was_hold{0x10};      
 
constexpr uint8_t enabled_function_buzzer{0x01};        
constexpr uint8_t enabled_function_led{0x02};           
constexpr uint8_t enabled_function_auto_refresh{0x04};  
 
constexpr uint8_t enabled_low_temperature_low{0x01};    
constexpr uint8_t enabled_med_temperature_low{0x02};    
constexpr uint8_t enabled_ave_temperature_low{0x04};    
constexpr uint8_t enabled_high_temperature_low{0x08};   
constexpr uint8_t enabled_low_temperature_high{0x10};   
constexpr uint8_t enabled_med_temperature_high{0x20};   
constexpr uint8_t enabled_ave_temperature_high{0x40};   
constexpr uint8_t enabled_high_temperature_high{0x80};  
 
enum class Refresh : uint8_t {
    Rate0_5Hz,  
    Rate1Hz,    
    Rate2Hz,    
    Rate4Hz,    
    Rate8Hz,    
    Rate16Hz,   
    Rate32Hz,   
    Rate64Hz,   
};
 
inline uint16_t celsius_to_raw(const float f)
{
    // Clamp in float before converting, so that NaN or a huge value does not overflow the integer conversion
    const float v{std::fmax(std::fmin((f + 64) * 128, 65535.f), 0.f)};
    return static_cast<uint16_t>(std::round(v));
}
inline float raw_to_celsius(const uint16_t u16)
{
    return u16 / 128.0f - 64;
}
 
#pragma pack(push)
#pragma pack(1)
struct Data {
    uint8_t subpage{};  
    union {
        uint16_t temp[8]{};  
        struct {
            uint16_t median_temperature;     
            uint16_t average_temperature;    
            uint16_t most_diff_temperature;  
            uint8_t most_diff_x;             
            uint8_t most_diff_y;             
            uint16_t lowest_temperature;     
            uint8_t lowest_diff_x;           
            uint8_t lowest_diff_y;           
            uint16_t highest_temperature;    
            uint8_t highest_diff_x;          
            uint8_t highest_diff_y;          
        };
    };
    uint16_t raw[384]{};  
 
    inline float medianTemperature() const
    {
        return thermal2::raw_to_celsius(temp[0]);
    }
    inline float averageTemperature() const
    {
        return thermal2::raw_to_celsius(temp[1]);
    }
    inline float mostDiffTemperature() const
    {
        return thermal2::raw_to_celsius(temp[2]);
    }
    inline float lowestTemperature() const
    {
        return thermal2::raw_to_celsius(temp[4]);
    }
    inline float highestTemperature() const
    {
        return thermal2::raw_to_celsius(temp[6]);
    }
 
    inline float temperature(const uint_fast16_t idx) const
    {
        return (idx < 384) ? thermal2::raw_to_celsius(raw[idx]) : std::numeric_limits<float>::quiet_NaN();
    }
};
#pragma pack(pop)
 
}  // namespace thermal2
 
}  // namespace unit
}  // namespace m5
#endif