unit_ak8963.hpp

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/*
 * SPDX-FileCopyrightText: 2026 M5Stack Technology CO LTD
 *
 * SPDX-License-Identifier: MIT
 */
#ifndef M5_UNIT_IMU_UNIT_UNIT_AK8963_HPP
#define M5_UNIT_IMU_UNIT_UNIT_AK8963_HPP
 
#include <M5UnitComponent.hpp>
#include <m5_utility/container/circular_buffer.hpp>
#include <memory>
#include "unit_ak8963_data.hpp"
#include "../imu/imu_data_source.hpp"
 
namespace m5 {
namespace unit {
 
class UnitAK8963 : public Component,
                   public PeriodicMeasurementAdapter<UnitAK8963, ak8963::Data>,
                   public m5::imu::IMUDataSource {
    M5_UNIT_COMPONENT_HPP_BUILDER(UnitAK8963, 0x0C);
 
public:
    struct config_t {
        bool start_periodic{true};
        ak8963::MeasurementMode measurement_mode{ak8963::MeasurementMode::Cont100Hz};
        ak8963::OutputBit output_bit{ak8963::OutputBit::Bit16};
    };
 
    explicit UnitAK8963(const uint8_t addr = DEFAULT_ADDRESS);
    virtual ~UnitAK8963()
    {
    }
 
    virtual bool begin() override;
    virtual void update(const bool force = false) override;
 
    config_t config() const
    {
        return _cfg;
    }
    void config(const config_t& cfg)
    {
        _cfg = cfg;
    }
 
    bool softReset();
 
 
    bool writeMeasurementMode(const ak8963::MeasurementMode mode, const ak8963::OutputBit bit);
    bool readMeasurementMode(ak8963::MeasurementMode& mode, ak8963::OutputBit& bit) const;
 
 
    bool startPeriodicMeasurement(const ak8963::MeasurementMode mode, const ak8963::OutputBit bit);
    bool startPeriodicMeasurement();
    bool stopPeriodicMeasurement();
 
 
    bool sleep() override;
    bool wakeup() override;
 
    virtual m5::imu::Capability imuSpec() const override
    {
        return m5::imu::Capability::Mag;
    }
    virtual m5::imu::Capability readImuRaw(m5::imu::imu_raw_data_t& out) override;
    virtual void imuConvertParam(m5::imu::imu_convert_param_t& out) const override;
 
protected:
    bool start_periodic_measurement(const ak8963::MeasurementMode mode, const ak8963::OutputBit bit);
    bool start_periodic_measurement();
    bool stop_periodic_measurement();
    bool read_measurement(ak8963::Data& d);
    bool read_sensitivity(std::array<uint8_t, 3>& asa);
 
    M5_UNIT_COMPONENT_PERIODIC_MEASUREMENT_ADAPTER_HPP_BUILDER(UnitAK8963, ak8963::Data);
 
private:
    config_t _cfg{};
    // Live state, seeded from _cfg by begin() and thereafter owned by writeMeasurementMode(); _cfg
    // is only ever read in begin()
    ak8963::MeasurementMode _mode{ak8963::MeasurementMode::Cont100Hz};
    ak8963::OutputBit _bit{ak8963::OutputBit::Bit16};
    std::array<uint8_t, 3> _asa{};  // Per-axis sensitivity adjustment (read once in begin, FUSE-ROM)
    uint32_t _pushed{}, _consumed{};
    std::unique_ptr<m5::container::CircularBuffer<ak8963::Data>> _data{};
};
 
namespace ak8963 {
constexpr uint32_t DEFAULT_STORED_SIZE{4};
 
namespace command {
constexpr uint8_t REG_WIA{0x00};    // WHO_AM_I = 0x48
constexpr uint8_t REG_ST1{0x02};    // burst start: ST1 + X/Y/Z(LE) + ST2 = 8 bytes
constexpr uint8_t REG_CNTL1{0x0A};  // bits[3:0] mode, bit4 = 16bit
constexpr uint8_t REG_CNTL2{0x0B};  // bit0 = SRST
constexpr uint8_t REG_ASAX{0x10};   // ASAX/ASAY/ASAZ (FUSE-ROM only)
}  // namespace command
}  // namespace ak8963
 
}  // namespace unit
}  // namespace m5
#endif