Counter Class Reference

#include <Counter.h>

Inheritance diagram for Counter:

Public Types
enum	Mode { kTwoPulse =0, kSemiperiod =1, kPulseLength =2, kExternalDirection =3 }
Public Types inherited from CounterBase
enum	EncodingType { k1X, k2X, k4X }

Public Member Functions
	Counter ()
	Counter (uint32_t channel)
	Counter (uint8_t moduleNumber, uint32_t channel)
	Counter (DigitalSource *source)
	Counter (DigitalSource &source)
	Counter (AnalogTrigger *trigger)
	Counter (AnalogTrigger &trigger)
	Counter (EncodingType encodingType, DigitalSource *upSource, DigitalSource *downSource, bool inverted)
virtual	~Counter ()
void	SetUpSource (uint32_t channel)
void	SetUpSource (uint8_t moduleNumber, uint32_t channel)
void	SetUpSource (AnalogTrigger *analogTrigger, AnalogTriggerOutput::Type triggerType)
void	SetUpSource (AnalogTrigger &analogTrigger, AnalogTriggerOutput::Type triggerType)
void	SetUpSource (DigitalSource *source)
void	SetUpSource (DigitalSource &source)
void	SetUpSourceEdge (bool risingEdge, bool fallingEdge)
void	ClearUpSource ()
void	SetDownSource (uint32_t channel)
void	SetDownSource (uint8_t moduleNumber, uint32_t channel)
void	SetDownSource (AnalogTrigger *analogTrigger, AnalogTriggerOutput::Type triggerType)
void	SetDownSource (AnalogTrigger &analogTrigger, AnalogTriggerOutput::Type triggerType)
void	SetDownSource (DigitalSource *source)
void	SetDownSource (DigitalSource &source)
void	SetDownSourceEdge (bool risingEdge, bool fallingEdge)
void	ClearDownSource ()
void	SetUpDownCounterMode ()
void	SetExternalDirectionMode ()
void	SetSemiPeriodMode (bool highSemiPeriod)
void	SetPulseLengthMode (float threshold)
void	SetReverseDirection (bool reverseDirection)
void	Start ()
int32_t	Get ()
void	Reset ()
void	Stop ()
double	GetPeriod ()
void	SetMaxPeriod (double maxPeriod)
void	SetUpdateWhenEmpty (bool enabled)
bool	GetStopped ()
bool	GetDirection ()
void	SetSamplesToAverage (int samplesToAverage)
int	GetSamplesToAverage ()
uint32_t	GetIndex ()
void	UpdateTable ()
void	StartLiveWindowMode ()
void	StopLiveWindowMode ()
virtual std::string	GetSmartDashboardType ()
void	InitTable (ITable *subTable)
ITable *	GetTable ()
Public Member Functions inherited from SensorBase
	SensorBase ()
virtual	~SensorBase ()
Public Member Functions inherited from ErrorBase
virtual Error &	GetError ()
	Retrieve the current error. Get the current error information associated with this sensor.
virtual const Error &	GetError () const
virtual void	SetErrnoError (const char *contextMessage, const char *filename, const char *function, uint32_t lineNumber) const
	Set error information associated with a C library call that set an error to the "errno" global variable. More...
virtual void	SetImaqError (int success, const char *contextMessage, const char *filename, const char *function, uint32_t lineNumber) const
	Set the current error information associated from the nivision Imaq API. More...
virtual void	SetError (Error::Code code, const char *contextMessage, const char *filename, const char *function, uint32_t lineNumber) const
	Set the current error information associated with this sensor. More...
virtual void	SetWPIError (const char *errorMessage, const char *contextMessage, const char *filename, const char *function, uint32_t lineNumber) const
	Set the current error information associated with this sensor. More...
virtual void	CloneError (ErrorBase *rhs) const
virtual void	ClearError () const
	Clear the current error information associated with this sensor.
virtual bool	StatusIsFatal () const
	Check if the current error code represents a fatal error. More...

Protected Attributes
DigitalSource *	m_upSource
	What makes the counter count up.
DigitalSource *	m_downSource
	What makes the counter count down.
tCounter *	m_counter
	The FPGA counter object.
Protected Attributes inherited from ErrorBase
Error	m_error

Additional Inherited Members
Static Public Member Functions inherited from SensorBase
static void	DeleteSingletons ()
static uint32_t	GetDefaultAnalogModule ()
static uint32_t	GetDefaultDigitalModule ()
static uint32_t	GetDefaultSolenoidModule ()
static bool	CheckAnalogModule (uint8_t moduleNumber)
static bool	CheckDigitalModule (uint8_t moduleNumber)
static bool	CheckPWMModule (uint8_t moduleNumber)
static bool	CheckRelayModule (uint8_t moduleNumber)
static bool	CheckSolenoidModule (uint8_t moduleNumber)
static bool	CheckDigitalChannel (uint32_t channel)
static bool	CheckRelayChannel (uint32_t channel)
static bool	CheckPWMChannel (uint32_t channel)
static bool	CheckAnalogChannel (uint32_t channel)
static bool	CheckSolenoidChannel (uint32_t channel)
Static Public Member Functions inherited from ErrorBase
static void	SetGlobalError (Error::Code code, const char *contextMessage, const char *filename, const char *function, uint32_t lineNumber)
static void	SetGlobalWPIError (const char *errorMessage, const char *contextMessage, const char *filename, const char *function, uint32_t lineNumber)
static Error &	GetGlobalError ()
Static Public Attributes inherited from SensorBase
static const uint32_t	kSystemClockTicksPerMicrosecond = 40
static const uint32_t	kDigitalChannels = 14
static const uint32_t	kAnalogChannels = 8
static const uint32_t	kAnalogModules = 2
static const uint32_t	kDigitalModules = 2
static const uint32_t	kSolenoidChannels = 8
static const uint32_t	kSolenoidModules = 2
static const uint32_t	kPwmChannels = 10
static const uint32_t	kRelayChannels = 8
static const uint32_t	kChassisSlots = 8
Protected Member Functions inherited from SensorBase
void	AddToSingletonList ()
Protected Member Functions inherited from ErrorBase
	ErrorBase ()
	Initialize the instance status to 0 for now.
Static Protected Attributes inherited from ErrorBase
static SEM_ID	_globalErrorMutex = semMCreate(SEM_Q_PRIORITY | SEM_DELETE_SAFE | SEM_INVERSION_SAFE)
static Error	_globalError

Detailed Description

Class for counting the number of ticks on a digital input channel. This is a general purpose class for counting repetitive events. It can return the number of counts, the period of the most recent cycle, and detect when the signal being counted has stopped by supplying a maximum cycle time.

Constructor & Destructor Documentation

Counter::Counter

(

)

Create an instance of a counter where no sources are selected. Then they all must be selected by calling functions to specify the upsource and the downsource independently.

Counter::Counter ( uint32_t  channel )

explicit

Create an instance of a Counter object. Create an up-Counter instance given a channel. The default digital module is assumed.

Counter::Counter	(	uint8_t	moduleNumber,
		uint32_t	channel
	)

Create an instance of a Counter object. Create an instance of an up-Counter given a digital module and a channel.

Parameters

moduleNumber	The digital module (1 or 2).
channel	The channel in the digital module

Counter::Counter ( DigitalSource *  source )

explicit

Create an instance of a counter from a Digital Input. This is used if an existing digital input is to be shared by multiple other objects such as encoders.

Counter::Counter ( AnalogTrigger *  trigger )

explicit

Create an instance of a Counter object. Create an instance of a simple up-Counter given an analog trigger. Use the trigger state output from the analog trigger.

Counter::~Counter ( )

virtual

Delete the Counter object.

Member Function Documentation

void Counter::ClearDownSource

(

)

Disable the down counting source to the counter.

void Counter::ClearUpSource

(

)

Disable the up counting source to the counter.

int32_t Counter::Get ( )

virtual

Read the current counter value. Read the value at this instant. It may still be running, so it reflects the current value. Next time it is read, it might have a different value.

Implements CounterBase.

bool Counter::GetDirection ( )

virtual

The last direction the counter value changed.

Returns

The last direction the counter value changed.

Implements CounterBase.

int Counter::GetSamplesToAverage

(

)

Get the Samples to Average which specifies the number of samples of the timer to average when calculating the period. Perform averaging to account for mechanical imperfections or as oversampling to increase resolution.

Returns

SamplesToAverage The number of samples being averaged (from 1 to 127)

bool Counter::GetStopped ( )

virtual

Determine if the clock is stopped. Determine if the clocked input is stopped based on the MaxPeriod value set using the SetMaxPeriod method. If the clock exceeds the MaxPeriod, then the device (and counter) are assumed to be stopped and it returns true.

Returns

Returns true if the most recent counter period exceeds the MaxPeriod value set by SetMaxPeriod.

Implements CounterBase.

void Counter::Reset ( )

virtual

Reset the Counter to zero. Set the counter value to zero. This doesn't effect the running state of the counter, just sets the current value to zero.

Implements CounterBase.

void Counter::SetDownSource

(

uint32_t

channel

)

Set the down counting source to be a digital input channel. The slot will be set to the default digital module slot.

void Counter::SetDownSource	(	uint8_t	moduleNumber,
		uint32_t	channel
	)

Set the down counting source to be a digital input slot and channel.

Parameters

moduleNumber	The digital module (1 or 2).
channel	The digital channel (1..14).

void Counter::SetDownSource	(	AnalogTrigger *	analogTrigger,
		AnalogTriggerOutput::Type	triggerType
	)

Set the down counting source to be an analog trigger.

Parameters

analogTrigger	The analog trigger object that is used for the Down Source
triggerType	The analog trigger output that will trigger the counter.

void Counter::SetDownSource	(	AnalogTrigger &	analogTrigger,
		AnalogTriggerOutput::Type	triggerType
	)

Set the down counting source to be an analog trigger.

Parameters

analogTrigger	The analog trigger object that is used for the Down Source
triggerType	The analog trigger output that will trigger the counter.

void Counter::SetDownSource

(

DigitalSource *

source

)

Set the source object that causes the counter to count down. Set the down counting DigitalSource.

void Counter::SetDownSource

(

DigitalSource &

source

)

Set the source object that causes the counter to count down. Set the down counting DigitalSource.

void Counter::SetDownSourceEdge	(	bool	risingEdge,
		bool	fallingEdge
	)

Set the edge sensitivity on a down counting source. Set the down source to either detect rising edges or falling edges.

void Counter::SetExternalDirectionMode

(

)

Set external direction mode on this counter. Counts are sourced on the Up counter input. The Down counter input represents the direction to count.

void Counter::SetMaxPeriod ( double  maxPeriod )

virtual

Set the maximum period where the device is still considered "moving". Sets the maximum period where the device is considered moving. This value is used to determine the "stopped" state of the counter using the GetStopped method.

Parameters

maxPeriod

The maximum period where the counted device is considered moving in seconds.

Implements CounterBase.

void Counter::SetPulseLengthMode

(

float

threshold

)

Configure the counter to count in up or down based on the length of the input pulse. This mode is most useful for direction sensitive gear tooth sensors.

Parameters

threshold

The pulse length beyond which the counter counts the opposite direction. Units are seconds.

void Counter::SetReverseDirection

(

bool

reverseDirection

)

Set the Counter to return reversed sensing on the direction. This allows counters to change the direction they are counting in the case of 1X and 2X quadrature encoding only. Any other counter mode isn't supported.

Parameters

reverseDirection

true if the value counted should be negated.

void Counter::SetSamplesToAverage

(

int

samplesToAverage

)

Set the Samples to Average which specifies the number of samples of the timer to average when calculating the period. Perform averaging to account for mechanical imperfections or as oversampling to increase resolution.

Parameters

samplesToAverage

The number of samples to average from 1 to 127.

void Counter::SetSemiPeriodMode

(

bool

highSemiPeriod

)

Set Semi-period mode on this counter. Counts up on both rising and falling edges.

void Counter::SetUpdateWhenEmpty

(

bool

enabled

)

Select whether you want to continue updating the event timer output when there are no samples captured. The output of the event timer has a buffer of periods that are averaged and posted to a register on the FPGA. When the timer detects that the event source has stopped (based on the MaxPeriod) the buffer of samples to be averaged is emptied. If you enable the update when empty, you will be notified of the stopped source and the event time will report 0 samples. If you disable update when empty, the most recent average will remain on the output until a new sample is acquired. You will never see 0 samples output (except when there have been no events since an FPGA reset) and you will likely not see the stopped bit become true (since it is updated at the end of an average and there are no samples to average).

void Counter::SetUpDownCounterMode

(

)

Set standard up / down counting mode on this counter. Up and down counts are sourced independently from two inputs.

void Counter::SetUpSource

(

uint32_t

channel

)

Set the upsource for the counter as a digital input channel. The slot will be the default digital module slot.

void Counter::SetUpSource	(	uint8_t	moduleNumber,
		uint32_t	channel
	)

Set the up source for the counter as digital input channel and slot.

Parameters

moduleNumber	The digital module (1 or 2).
channel	The digital channel (1..14).

void Counter::SetUpSource	(	AnalogTrigger *	analogTrigger,
		AnalogTriggerOutput::Type	triggerType
	)

Set the up counting source to be an analog trigger.

Parameters

analogTrigger	The analog trigger object that is used for the Up Source
triggerType	The analog trigger output that will trigger the counter.

void Counter::SetUpSource	(	AnalogTrigger &	analogTrigger,
		AnalogTriggerOutput::Type	triggerType
	)

Set the up counting source to be an analog trigger.

Parameters

analogTrigger	The analog trigger object that is used for the Up Source
triggerType	The analog trigger output that will trigger the counter.

void Counter::SetUpSource

(

DigitalSource *

source

)

Set the source object that causes the counter to count up. Set the up counting DigitalSource.

void Counter::SetUpSource

(

DigitalSource &

source

)

Set the source object that causes the counter to count up. Set the up counting DigitalSource.

void Counter::SetUpSourceEdge	(	bool	risingEdge,
		bool	fallingEdge
	)

Set the edge sensitivity on an up counting source. Set the up source to either detect rising edges or falling edges.

void Counter::Start ( )

virtual

Start the Counter counting. This enables the counter and it starts accumulating counts from the associated input channel. The counter value is not reset on starting, and still has the previous value.

Implements CounterBase.

void Counter::Stop ( )

virtual

Stop the Counter. Stops the counting but doesn't effect the current value.

Implements CounterBase.

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The documentation for this class was generated from the following files:

• Counter.h
• Counter.cpp