Files
allwpilib/wpilibc/athena/include/AnalogTriggerOutput.h
Peter Mitrano e71f454b9d Renamed folders for consistency, using sim/athena/shared schema (#27)
Rename the following folders:
hal/lib/Athena -> hal/lib/athena
hal/lib/Desktop -> hal/lib/sim
hal/lib/Shared -> hal/lib/shared
wpilibc/Athena -> wpilibc/athena
wpilibc/simulation -> wpilibc/sim

Windows users may need to run gradlew clean after updating.
2016-05-22 14:55:51 -07:00

66 lines
3.1 KiB
C++

/*----------------------------------------------------------------------------*/
/* Copyright (c) FIRST 2008-2016. All Rights Reserved. */
/* Open Source Software - may be modified and shared by FRC teams. The code */
/* must be accompanied by the FIRST BSD license file in the root directory of */
/* the project. */
/*----------------------------------------------------------------------------*/
#pragma once
#include "DigitalSource.h"
class AnalogTrigger;
/** Class to represent a specific output from an analog trigger.
* This class is used to get the current output value and also as a
* DigitalSource to provide routing of an output to digital subsystems on the
* FPGA such as Counter, Encoder, and Interrupt.
*
* The TriggerState output indicates the primary output value of the trigger.
* If the analog signal is less than the lower limit, the output is false. If
* the analog value is greater than the upper limit, then the output is true.
* If the analog value is in between, then the trigger output state maintains
* its most recent value.
*
* The InWindow output indicates whether or not the analog signal is inside the
* range defined by the limits.
*
* The RisingPulse and FallingPulse outputs detect an instantaneous transition
* from above the upper limit to below the lower limit, and vise versa. These
* pulses represent a rollover condition of a sensor and can be routed to an up
* / down couter or to interrupts. Because the outputs generate a pulse, they
* cannot be read directly. To help ensure that a rollover condition is not
* missed, there is an average rejection filter available that operates on the
* upper 8 bits of a 12 bit number and selects the nearest outlyer of 3 samples.
* This will reject a sample that is (due to averaging or sampling) errantly
* between the two limits. This filter will fail if more than one sample in a
* row is errantly in between the two limits. You may see this problem if
* attempting to use this feature with a mechanical rollover sensor, such as a
* 360 degree no-stop potentiometer without signal conditioning, because the
* rollover transition is not sharp / clean enough. Using the averaging engine
* may help with this, but rotational speeds of the sensor will then be limited.
*/
class AnalogTriggerOutput : public DigitalSource {
friend class AnalogTrigger;
public:
virtual ~AnalogTriggerOutput();
bool Get() const;
// DigitalSource interface
virtual uint32_t GetChannelForRouting() const override;
virtual uint32_t GetModuleForRouting() const override;
virtual bool GetAnalogTriggerForRouting() const override;
protected:
AnalogTriggerOutput(const AnalogTrigger& trigger,
AnalogTriggerType outputType);
private:
// Uses reference rather than smart pointer because a user can not construct
// an AnalogTriggerOutput themselves and because the AnalogTriggerOutput
// should always be in scope at the same time as an AnalogTrigger.
const AnalogTrigger& m_trigger;
AnalogTriggerType m_outputType;
};