Program Listing for File encoder.h

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// Code in this file is inspired by:
// https://github.com/hbrobotics/ros_arduino_bridge/blob/indigo-devel/ros_arduino_firmware/src/libraries/ROSArduinoBridge/encoder_driver.h
//
// ----------------------------------------------------------------------------
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//
// Software License Agreement (BSD License)
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// BSD 3-Clause License
//
// Copyright (c) 2023, Ekumen Inc.
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// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
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#pragma once

#include <stdint.h>

#include "interrupt_in.h"

namespace andino {

class Encoder {
 public:
  Encoder(const InterruptIn* channel_a_interrupt_in, const InterruptIn* channel_b_interrupt_in)
      : channel_a_interrupt_in_(channel_a_interrupt_in),
        channel_b_interrupt_in_(channel_b_interrupt_in) {}

  void begin();

  long read();

  void reset();

 private:
  static constexpr int8_t kTicksDelta[]{0, 1, -1, 0, -1, 0, 0, 1, 1, 0, 0, -1, 0, -1, 1, 0};

  static constexpr int kInstancesMax{2};

  static const InterruptIn::InterruptCallback kCallbacks[kInstancesMax];

  static void callback_0();

  static void callback_1();

  void callback();

  static Encoder* instances_[kInstancesMax];

  static int instance_count_;

  const InterruptIn* channel_a_interrupt_in_;

  const InterruptIn* channel_b_interrupt_in_;

  uint8_t state_{0x00};

  volatile long count_{0L};
};

}  // namespace andino