unit_bmm150.hpp

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/*
 * SPDX-FileCopyrightText: 2026 M5Stack Technology CO LTD
 *
 * SPDX-License-Identifier: MIT
 */
#ifndef M5_UNIT_IMU_UNIT_UNIT_BMM150_HPP
#define M5_UNIT_IMU_UNIT_UNIT_BMM150_HPP
 
#include <M5UnitComponent.hpp>
#include <m5_utility/container/circular_buffer.hpp>
#include <memory>
#include "unit_bmm150_data.hpp"
#include "../imu/imu_data_source.hpp"
 
namespace m5 {
namespace unit {
 
class UnitBMM150 : public Component,
                   public PeriodicMeasurementAdapter<UnitBMM150, bmm150::Data>,
                   public m5::imu::IMUDataSource {
    M5_UNIT_COMPONENT_HPP_BUILDER(UnitBMM150, 0x10);
 
public:
    struct config_t {
        bool start_periodic{true};
        bmm150::Preset preset{bmm150::Preset::Regular};
        bmm150::DataRate rate{bmm150::DataRate::Rate30Hz};
    };
 
    explicit UnitBMM150(const uint8_t addr = DEFAULT_ADDRESS);
    virtual ~UnitBMM150()
    {
    }
 
    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 writePreset(const bmm150::Preset preset);
    bool writeRepetition(const uint8_t rep_xy, const uint8_t rep_z);
    bool readRepetition(uint8_t& rep_xy, uint8_t& rep_z);
    bool writeDataRate(const bmm150::DataRate rate);
    bool readDataRate(bmm150::DataRate& rate);
 
    bool softReset();
 
 
    bool startPeriodicMeasurement(const bmm150::DataRate rate, const bmm150::Preset preset);
    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 bmm150::DataRate rate, const bmm150::Preset preset);
    bool start_periodic_measurement();
    bool stop_periodic_measurement();
    bool read_measurement(bmm150::Data& d);
    // Rate/repetition writers without the "does it fit" check. Needed because the public setters
    // validate against whatever is on the device right now, which makes a valid target pair fail
    // when applied one at a time: going from 30Hz/Regular to 10Hz/HighAccuracy has to pass through
    // one combination that does not fit whichever half is written first. start_periodic_measurement()
    // validates the pair up front instead and then writes both unchecked.
    bool write_repetition_unchecked(const uint8_t rep_xy, const uint8_t rep_z);
    bool write_data_rate_unchecked(const bmm150::DataRate rate);
    bool write_register8_verified(const uint8_t reg, const uint8_t val);
    bool read_trim(bmm150::trim_t& trim);
 
    M5_UNIT_COMPONENT_PERIODIC_MEASUREMENT_ADAPTER_HPP_BUILDER(UnitBMM150, bmm150::Data);
 
private:
    config_t _cfg{};
    bmm150::trim_t _trim{};
    uint32_t _pushed{}, _consumed{};  // readImuRaw pop counters (do not disturb latest()/oldest())
    std::unique_ptr<m5::container::CircularBuffer<bmm150::Data>> _data{};
};
 
namespace bmm150 {
constexpr uint32_t DEFAULT_STORED_SIZE{4};
 
namespace command {
// Register addresses (I2C addr 0x10/0x11/0x12/0x13 by CSB/SDO pins)
constexpr uint8_t REG_CHIP_ID{0x40};
constexpr uint8_t REG_DATA_X_LSB{0x42};  // 8 bytes: X/Y/Z/RHALL burst (bit0 of [6] = DRDY)
constexpr uint8_t REG_INT_STATUS{0x4A};
constexpr uint8_t REG_POWER_CONTROL{0x4B};  // bit7+bit1 = SoftReset / bit0 = PowerControl
constexpr uint8_t REG_OP_MODE{0x4C};        // bit5:3 = DataRate / bit2:1 = Opmode
constexpr uint8_t REG_REP_XY{0x51};
constexpr uint8_t REG_REP_Z{0x52};
constexpr uint8_t REG_TRIM_START{0x5D};  // 21 bytes: 0x5D..0x71 (see read_trim())
}  // namespace command
}  // namespace bmm150
 
}  // namespace unit
}  // namespace m5
#endif