ADXL345_I2C.hpp

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// Copyright (c) FIRST and other WPILib contributors.
// Open Source Software; you can modify and/or share it under the terms of
// the WPILib BSD license file in the root directory of this project.
 
#pragma once
 
#include "wpi/hal/SimDevice.hpp"
#include "wpi/hardware/bus/I2C.hpp"
#include "wpi/nt/NTSendable.hpp"
#include "wpi/util/sendable/SendableHelper.hpp"
 
namespace wpi {
 
/**
 * ADXL345 Accelerometer on I2C.
 *
 * This class allows access to a Analog Devices ADXL345 3-axis accelerometer on
 * an I2C bus. This class assumes the default (not alternate) sensor address of
 * 0x1D (7-bit address).
 */
class ADXL345_I2C : public wpi::nt::NTSendable,
                    public wpi::util::SendableHelper<ADXL345_I2C> {
 public:
  /**
   * Accelerometer range.
   */
  enum Range {
    /// 2 Gs max.
    kRange_2G = 0,
    /// 4 Gs max.
    kRange_4G = 1,
    /// 8 Gs max.
    kRange_8G = 2,
    /// 16 Gs max.
    kRange_16G = 3
  };
 
  /**
   * Accelerometer axes.
   */
  enum Axes {
    /// X axis.
    kAxis_X = 0x00,
    /// Y axis.
    kAxis_Y = 0x02,
    /// Z axis.
    kAxis_Z = 0x04
  };
 
  /**
   * Container type for accelerations from all axes.
   */
  struct AllAxes {
    /// Acceleration along the X axis in g-forces.
    double XAxis = 0.0;
    /// Acceleration along the Y axis in g-forces.
    double YAxis = 0.0;
    /// Acceleration along the Z axis in g-forces.
    double ZAxis = 0.0;
  };
 
  /// Default I2C device address.
  static constexpr int kAddress = 0x1D;
 
  /**
   * Constructs the ADXL345 Accelerometer over I2C.
   *
   * @param port          The I2C port the accelerometer is attached to
   * @param range         The range (+ or -) that the accelerometer will measure
   * @param deviceAddress The I2C address of the accelerometer (0x1D or 0x53)
   */
  explicit ADXL345_I2C(I2C::Port port, Range range = kRange_2G,
                       int deviceAddress = kAddress);
  ~ADXL345_I2C() override = default;
 
  ADXL345_I2C(ADXL345_I2C&&) = default;
  ADXL345_I2C& operator=(ADXL345_I2C&&) = default;
 
  I2C::Port GetI2CPort() const;
  int GetI2CDeviceAddress() const;
 
  /**
   * Set the measuring range of the accelerometer.
   *
   * @param range The maximum acceleration, positive or negative, that the
   *     accelerometer will measure.
   */
  void SetRange(Range range);
 
  /**
   * Returns the acceleration along the X axis in g-forces.
   *
   * @return The acceleration along the X axis in g-forces.
   */
  double GetX();
 
  /**
   * Returns the acceleration along the Y axis in g-forces.
   *
   * @return The acceleration along the Y axis in g-forces.
   */
  double GetY();
 
  /**
   * Returns the acceleration along the Z axis in g-forces.
   *
   * @return The acceleration along the Z axis in g-forces.
   */
  double GetZ();
 
  /**
   * Get the acceleration of one axis in Gs.
   *
   * @param axis The axis to read from.
   * @return Acceleration of the ADXL345 in Gs.
   */
  virtual double GetAcceleration(Axes axis);
 
  /**
   * Get the acceleration of all axes in Gs.
   *
   * @return An object containing the acceleration measured on each axis of the
   *         ADXL345 in Gs.
   */
  virtual AllAxes GetAccelerations();
 
  void InitSendable(wpi::nt::NTSendableBuilder& builder) override;
 
 private:
  I2C m_i2c;
 
  wpi::hal::SimDevice m_simDevice;
  wpi::hal::SimEnum m_simRange;
  wpi::hal::SimDouble m_simX;
  wpi::hal::SimDouble m_simY;
  wpi::hal::SimDouble m_simZ;
 
  static constexpr int kPowerCtlRegister = 0x2D;
  static constexpr int kDataFormatRegister = 0x31;
  static constexpr int kDataRegister = 0x32;
  static constexpr double kGsPerLSB = 0.00390625;
 
  enum PowerCtlFields {
    kPowerCtl_Link = 0x20,
    kPowerCtl_AutoSleep = 0x10,
    kPowerCtl_Measure = 0x08,
    kPowerCtl_Sleep = 0x04
  };
 
  enum DataFormatFields {
    kDataFormat_SelfTest = 0x80,
    kDataFormat_SPI = 0x40,
    kDataFormat_IntInvert = 0x20,
    kDataFormat_FullRes = 0x08,
    kDataFormat_Justify = 0x04
  };
};
 
}  // namespace wpi