frc971/wpilib/sensor_reader.h

#ifndef FRC971_WPILIB_SENSOR_READER_H_
#define FRC971_WPILIB_SENSOR_READER_H_

#include <atomic>
#include <chrono>

#include "aos/stl_mutex/stl_mutex.h"
#include "aos/time/time.h"
#include "frc971/wpilib/ahal/DigitalGlitchFilter.h"
#include "frc971/wpilib/ahal/DigitalInput.h"
#include "frc971/wpilib/dma.h"
#include "frc971/wpilib/dma_edge_counting.h"

using ::aos::monotonic_clock;
namespace chrono = ::std::chrono;

namespace frc971 {
namespace wpilib {

class SensorReader {
 public:
  SensorReader();

  // Updates the fast and medium encoder filter frequencies.
  void UpdateFastEncoderFilterHz(int hz);
  void UpdateMediumEncoderFilterHz(int hz);

  // Sets the left drivetrain encoder.
  void set_drivetrain_left_encoder(::std::unique_ptr<frc::Encoder> encoder);

  // Sets the right drivetrain encoder.
  void set_drivetrain_right_encoder(::std::unique_ptr<frc::Encoder> encoder);

  // Sets the dma.
  void set_dma(::std::unique_ptr<DMA> dma);

  // Sets the pwm trigger.
  void set_pwm_trigger(::std::unique_ptr<frc::DigitalInput> pwm_trigger);

  // Stops the pwm trigger on the next iteration.
  void Quit() { run_ = false; }

  virtual void RunIteration() = 0;

  void operator()();

 protected:
  frc::DigitalGlitchFilter fast_encoder_filter_, medium_encoder_filter_;

  ::std::unique_ptr<frc::Encoder> drivetrain_left_encoder_,
      drivetrain_right_encoder_;

 private:
  // Uses the pwm trigger to find the pwm cycle width and offset for that
  // iteration.
  void RunPWMDetecter();

  ::std::unique_ptr<frc::DigitalInput> pwm_trigger_;

  // Mutex to manage access to the period and tick time variables.
  ::aos::stl_mutex tick_time_mutex_;
  monotonic_clock::time_point last_tick_time_monotonic_timepoint_ =
      monotonic_clock::min_time;
  chrono::nanoseconds last_period_;

  ::std::unique_ptr<::frc971::wpilib::DMASynchronizer> dma_synchronizer_;

  ::std::atomic<bool> run_{true};
};

}  // namespace wpilib
}  // namespace frc971

#endif  // FRC971_WPILIB_SENSOR_READER_H_