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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 <memory>
#include <hal/DutyCycle.h>
#include <hal/Types.h>
#include <units/time.h>
#include <wpi/sendable/Sendable.h>
#include <wpi/sendable/SendableHelper.h>
namespace frc {
class DigitalSource;
class AnalogTrigger;
class DMA;
class DMASample;
/**
* Class to read a duty cycle PWM input.
*
* <p>PWM input signals are specified with a frequency and a ratio of high to
* low in that frequency. There are 8 of these in the roboRIO, and they can be
* attached to any DigitalSource.
*
* <p>These can be combined as the input of an AnalogTrigger to a Counter in
* order to implement rollover checking.
*
*/
class DutyCycle : public wpi::Sendable, public wpi::SendableHelper<DutyCycle> {
friend class AnalogTrigger;
friend class DMA;
friend class DMASample;
public:
/**
* Constructs a DutyCycle input from a DigitalSource input.
*
* <p> This class does not own the inputted source.
*
* @param source The DigitalSource to use.
*/
explicit DutyCycle(DigitalSource& source);
/**
* Constructs a DutyCycle input from a DigitalSource input.
*
* <p> This class does not own the inputted source.
*
* @param source The DigitalSource to use.
*/
explicit DutyCycle(DigitalSource* source);
/**
* Constructs a DutyCycle input from a DigitalSource input.
*
* <p> This class does not own the inputted source.
*
* @param source The DigitalSource to use.
*/
explicit DutyCycle(std::shared_ptr<DigitalSource> source);
DutyCycle(DutyCycle&&) = default;
DutyCycle& operator=(DutyCycle&&) = default;
/**
* Close the DutyCycle and free all resources.
*/
~DutyCycle() override = default;
/**
* Get the frequency of the duty cycle signal.
*
* @return frequency in Hertz
*/
int GetFrequency() const;
/**
* Get the output ratio of the duty cycle signal.
*
* <p> 0 means always low, 1 means always high.
*
* @return output ratio between 0 and 1
*/
double GetOutput() const;
/**
* Get the raw high time of the duty cycle signal.
*
* @return high time of last pulse
*/
units::second_t GetHighTime() const;
/**
* Get the scale factor of the output.
*
* <p> An output equal to this value is always high, and then linearly scales
* down to 0. Divide a raw result by this in order to get the
* percentage between 0 and 1. Used by DMA.
*
* @return the output scale factor
*/
unsigned int GetOutputScaleFactor() const;
/**
* Get the FPGA index for the DutyCycle.
*
* @return the FPGA index
*/
int GetFPGAIndex() const;
/**
* Get the channel of the source.
*
* @return the source channel
*/
int GetSourceChannel() const;
protected:
void InitSendable(wpi::SendableBuilder& builder) override;
private:
void InitDutyCycle();
std::shared_ptr<DigitalSource> m_source;
hal::Handle<HAL_DutyCycleHandle, HAL_FreeDutyCycle> m_handle;
};
} // namespace frc