edu.wpi.first.wpilibj

Class AnalogTriggerOutput

java.lang.Object

edu.wpi.first.wpilibj.SensorBase

edu.wpi.first.wpilibj.InterruptableSensorBase

edu.wpi.first.wpilibj.DigitalSource

edu.wpi.first.wpilibj.AnalogTriggerOutput

public class AnalogTriggerOutput
extends DigitalSource

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.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	AnalogTriggerOutput.AnalogTriggerOutputException Exceptions dealing with improper operation of the Analog trigger output
static class	AnalogTriggerOutput.AnalogTriggerType Defines the state in which the AnalogTrigger triggers

Field Summary

Fields inherited from class edu.wpi.first.wpilibj.DigitalSource

channels, m_channel, m_port

Fields inherited from class edu.wpi.first.wpilibj.InterruptableSensorBase

interrupts, m_interrupt, m_interruptIndex, m_isSynchronousInterrupt

Fields inherited from class edu.wpi.first.wpilibj.SensorBase

kAnalogInputChannels, kAnalogOutputChannels, kDigitalChannels, kPDPChannels, kPwmChannels, kRelayChannels, kSolenoidChannels, kSolenoidModules, kSystemClockTicksPerMicrosecond

Constructor Summary

Constructors

Constructor and Description
AnalogTriggerOutput(AnalogTrigger trigger, AnalogTriggerOutput.AnalogTriggerType outputType) Create an object that represents one of the four outputs from an analog trigger.

Method Summary

Modifier and Type	Method and Description
void	free() Free the resources used by this object
boolean	get() Get the state of the analog trigger output.
boolean	getAnalogTriggerForRouting() Is this an analog trigger
int	getChannelForRouting() Get the channel routing number
byte	getModuleForRouting() Get the module routing number

Methods inherited from class edu.wpi.first.wpilibj.DigitalSource

initDigitalPort

Methods inherited from class edu.wpi.first.wpilibj.InterruptableSensorBase

allocateInterrupts, cancelInterrupts, disableInterrupts, enableInterrupts, readFallingTimestamp, readRisingTimestamp, requestInterrupts, requestInterrupts, setUpSourceEdge, waitForInterrupt, waitForInterrupt

Methods inherited from class edu.wpi.first.wpilibj.SensorBase

checkAnalogInputChannel, checkAnalogOutputChannel, checkDigitalChannel, checkPDPChannel, checkPWMChannel, checkRelayChannel, checkSolenoidChannel, checkSolenoidModule, getDefaultSolenoidModule, setDefaultSolenoidModule

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AnalogTriggerOutput

public AnalogTriggerOutput(AnalogTrigger trigger,
                           AnalogTriggerOutput.AnalogTriggerType outputType)

Create an object that represents one of the four outputs from an analog trigger. Because this class derives from DigitalSource, it can be passed into routing functions for Counter, Encoder, etc.

Parameters:

trigger - The trigger for which this is an output.

outputType - An enum that specifies the output on the trigger to represent.

Method Detail

free

public void free()

Description copied from class: SensorBase

Free the resources used by this object

Overrides:

free in class DigitalSource

get

public boolean get()

Get the state of the analog trigger output.

Returns:

The state of the analog trigger output.

getChannelForRouting

public int getChannelForRouting()

Description copied from class: DigitalSource

Get the channel routing number

Overrides:

getChannelForRouting in class DigitalSource

Returns:

channel routing number

getModuleForRouting

public byte getModuleForRouting()

Description copied from class: DigitalSource

Get the module routing number

Overrides:

getModuleForRouting in class DigitalSource

Returns:

0

getAnalogTriggerForRouting

public boolean getAnalogTriggerForRouting()

Description copied from class: DigitalSource

Is this an analog trigger

Overrides:

getAnalogTriggerForRouting in class DigitalSource

Returns:

true if this is an analog trigger