ardupilot/libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.h

#pragma once

#include "RangeFinder.h"
#include "RangeFinder_Backend.h"
#include <AP_HAL/I2CDevice.h>

#define NUM_SF20_DATA_STREAMS 1

class AP_RangeFinder_LightWareI2C : public AP_RangeFinder_Backend
{

public:
    // static detection function
    static AP_RangeFinder_Backend *detect(RangeFinder::RangeFinder_State &_state,
                                          AP_RangeFinder_Params &_params,
                                          AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev);

    // update state
    void update(void) override;

protected:

    virtual MAV_DISTANCE_SENSOR _get_mav_distance_sensor_type() const override
    {
        return MAV_DISTANCE_SENSOR_LASER;
    }

private:

    uint16_t sf20_stream_val[NUM_SF20_DATA_STREAMS];
    int currentStreamSequenceIndex = 0;

    // constructor
    AP_RangeFinder_LightWareI2C(RangeFinder::RangeFinder_State &_state,
                                AP_RangeFinder_Params &_params,
                                AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev);

    bool write_bytes(uint8_t *write_buf_u8, uint32_t len_u8);
    void sf20_disable_address_tagging();
    bool sf20_send_and_expect(const char* send, const char* expected_reply);
    bool sf20_set_lost_signal_confirmations();
    void sf20_get_version(const char* send_msg, const char *reply_prefix, char reply[5]);
    bool sf20_wait_on_reply(uint8_t *rx_two_bytes);
    bool init();
    bool legacy_init();
    bool sf20_init();
    void sf20_init_streamRecovery();
    void legacy_timer();
    void sf20_timer();

    // get a reading
    bool legacy_get_reading(uint16_t &reading_cm);
    bool sf20_get_reading(uint16_t &reading_cm);
    bool sf20_parse_stream(uint8_t *stream_buf,
                           size_t *p_num_processed_chars,
                           const char *string_identifier,
                           uint16_t &val);
    void data_log(uint16_t *val);
    AP_HAL::OwnPtr<AP_HAL::I2CDevice> _dev;
};