unit_bmi270_data.hpp

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/*
 * SPDX-FileCopyrightText: 2026 M5Stack Technology CO LTD
 *
 * SPDX-License-Identifier: MIT
 */
#ifndef M5_UNIT_IMU_UNIT_UNIT_BMI270_DATA_HPP
#define M5_UNIT_IMU_UNIT_UNIT_BMI270_DATA_HPP
 
#include <array>
#include <cstdint>
#include "unit_bmm150_data.hpp"
 
namespace m5 {
namespace unit {
namespace bmi270 {
 
enum class AccelRange : uint8_t {
    G2,   
    G4,   
    G8,   
    G16,  
};
 
enum class GyroRange : uint8_t {
    DPS2000,  
    DPS1000,  
    DPS500,   
    DPS250,   
    DPS125,   
};
 
enum class AccelODR : uint8_t {
    Rate12_5Hz = 0x05,  
    Rate25Hz,           
    Rate50Hz,           
    Rate100Hz,          
    Rate200Hz,          
    Rate400Hz,          
    Rate800Hz,          
    Rate1600Hz,         
};
 
enum class GyroODR : uint8_t {
    Rate25Hz = 0x06,  
    Rate50Hz,         
    Rate100Hz,        
    Rate200Hz,        
    Rate400Hz,        
    Rate800Hz,        
    Rate1600Hz,       
    Rate3200Hz,       
};
 
enum class FilterPerf : uint8_t {
    PowerOptimized,  
    Performance,     
};
 
enum class AccelBwp : uint8_t {
    Osr4Avg1,  
    Osr2Avg2,  
    NormAvg4,  
    CicAvg8,   
    Avg16,     
    Avg32,     
    Avg64,     
    Avg128,    
};
 
enum class GyroBwp : uint8_t {
    Osr4,  
    Osr2,  
    Norm,  
};
 
constexpr bool bwp_fits(const FilterPerf perf, const AccelBwp bwp)
{
    return (perf == FilterPerf::PowerOptimized) ||
           (static_cast<uint8_t>(bwp) <= static_cast<uint8_t>(AccelBwp::CicAvg8));
}
 
constexpr uint8_t acc_conf_value(const FilterPerf perf, const AccelBwp bwp, const AccelODR odr)
{
    return static_cast<uint8_t>((static_cast<uint8_t>(perf) << 7) | (static_cast<uint8_t>(bwp) << 4) |
                                static_cast<uint8_t>(odr));
}
 
constexpr uint8_t gyr_conf_value(const FilterPerf perf, const GyroBwp bwp, const GyroODR odr)
{
    return static_cast<uint8_t>((static_cast<uint8_t>(perf) << 7) | (static_cast<uint8_t>(bwp) << 4) |
                                static_cast<uint8_t>(odr));
}
 
constexpr float accel_res(const AccelRange r)
{
    return (2.0f * (1 << static_cast<uint8_t>(r))) / 32768;
}
constexpr float gyro_res(const GyroRange r)
{
    return (2000.0f / (1 << static_cast<uint8_t>(r))) / 32768;
}
 
// Sampling interval (ms) per GyroODR raw register value, ceil(1000/Hz), indexed 0x00..0x0D
// (only 0x06..0x0D are valid GyroODR values; others are unused placeholders).
// constexpr namespace-scope array: internal linkage per translation unit (no ODR issue).
constexpr uint32_t GYRO_ODR_INTERVAL_MS[14] = {
    0,  0, 0, 0, 0, 0,  // 0x00..0x05 (unused)
    40,                 // 0x06 = 25Hz
    20,                 // 0x07 = 50Hz
    10,                 // 0x08 = 100Hz
    5,                  // 0x09 = 200Hz
    3,                  // 0x0A = 400Hz
    2,                  // 0x0B = 800Hz
    1,                  // 0x0C = 1600Hz
    1,                  // 0x0D = 3200Hz
};
 
constexpr uint32_t odr_interval_ms(const GyroODR odr)
{
    return GYRO_ODR_INTERVAL_MS[static_cast<uint8_t>(odr)];
}
 
struct Data {
    std::array<uint8_t, 12> raw{};  
    bmm150::Data mag{};
    bool aux_mag{false};  
 
    inline int16_t accel_x() const
    {
        return static_cast<int16_t>((raw[1] << 8) | raw[0]);
    }
    inline int16_t accel_y() const
    {
        return static_cast<int16_t>((raw[3] << 8) | raw[2]);
    }
    inline int16_t accel_z() const
    {
        return static_cast<int16_t>((raw[5] << 8) | raw[4]);
    }
    inline int16_t gyro_x() const
    {
        return static_cast<int16_t>((raw[7] << 8) | raw[6]);
    }
    inline int16_t gyro_y() const
    {
        return static_cast<int16_t>((raw[9] << 8) | raw[8]);
    }
    inline int16_t gyro_z() const
    {
        return static_cast<int16_t>((raw[11] << 8) | raw[10]);
    }
};
 
}  // namespace bmi270
}  // namespace unit
}  // namespace m5
#endif