imu_detect.hpp

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/*
 * SPDX-FileCopyrightText: 2026 M5Stack Technology CO LTD
 *
 * SPDX-License-Identifier: MIT
 */
#ifndef M5_UNIT_IMU_IMU_IMU_DETECT_HPP
#define M5_UNIT_IMU_IMU_IMU_DETECT_HPP
 
#include <cstdint>
#include <initializer_list>
 
namespace m5 {
namespace unit {
namespace imu {
 
enum class ImuKind : uint8_t {
    None,     
    MPU6050,  
    MPU6886,  
    MPU9250,  
    BMI270,   
    SH200Q,   
};
 
template <class ReadReg>
ImuKind detectBuiltinImu(ReadReg read)
{
    uint8_t id{};
 
    // MPU family: WHO_AM_I at 0x68 register 0x75.
    if (read(static_cast<uint8_t>(0x68), static_cast<uint8_t>(0x75), id)) {
        switch (id) {
            case 0x19:
                return ImuKind::MPU6886;
            case 0x68:
                return ImuKind::MPU6050;
            case 0x71:
                return ImuKind::MPU9250;
            default:
                break;  // not a known MPU id -> fall through to the BMI270 probe (BMI270 lives at 0x68 too)
        }
    }
 
    // BMI270: CHIP_ID 0x24 at register 0x00, on either candidate address.
    for (const uint8_t candidate : {static_cast<uint8_t>(0x68), static_cast<uint8_t>(0x69)}) {
        if (read(candidate, static_cast<uint8_t>(0x00), id) && id == 0x24) {
            return ImuKind::BMI270;
        }
    }
 
    // SH200Q: WHO_AM_I 0x18 at 0x6C register 0x30.
    if (read(static_cast<uint8_t>(0x6C), static_cast<uint8_t>(0x30), id) && id == 0x18) {
        return ImuKind::SH200Q;
    }
 
    return ImuKind::None;
}
 
}  // namespace imu
}  // namespace unit
}  // namespace m5
#endif