text: /* 
   * The MIT License (MIT)
   *
   * Copyright (c) 2019 Ha Thach (tinyusb.org) for Adafruit Industries
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  
  #ifndef BLEADAFRUIT_QUATERNION_H_
  #define BLEADAFRUIT_QUATERNION_H_
  
  // forward declaration
  class Adafruit_AHRS_FusionInterface;
  class Adafruit_Sensor_Calibration;
  
  class BLEAdafruitQuaternion : public BLEAdafruitSensor
  {
    public:
      static const uint8_t UUID128_SERVICE[16];
      static const uint8_t UUID128_CHR_DATA[16];
      static const uint8_t FUSION_MEASURE_RATIO = 10; // number of filter update for each measure report to client
  
      BLEAdafruitQuaternion(void);
      err_t begin(Adafruit_AHRS_FusionInterface* filter, Adafruit_Sensor* accel, Adafruit_Sensor* gyro, Adafruit_Sensor* mag);
      void setCalibration(Adafruit_Sensor_Calibration* calib);
  
    protected:
      void _update_timer(int32_t ms);
      void _measure_handler(void);
      void _notify_handler(uint16_t conn_hdl, uint16_t value);
  
      void _fitler_update(void);
  
    private:
      Adafruit_Sensor* _accel;
      Adafruit_Sensor* _gyro;
      Adafruit_Sensor* _mag;
  
      Adafruit_AHRS_FusionInterface* _filter;
      Adafruit_Sensor_Calibration* _calib;
      SoftwareTimer _filter_timer;
  
      // filter timer callback, 10x faster than period timer
      static void quaternion_filter_timer_cb(TimerHandle_t xTimer);
  };
  
  #endif /* BLEADAFRUIT_QUATERNION_H_ */
  