frc::Notifier Class Reference

Notifiers run a user-provided callback function on a separate thread. More...

#include <frc/Notifier.h>

Public Member Functions
	Notifier (std::function< void()> callback)
	Create a Notifier with the given callback. More...
template<typename Arg , typename... Args>
	Notifier (std::invocable< Arg, Args... > auto &&callback, Arg &&arg, Args &&... args)
	Notifier (int priority, std::function< void()> callback)
	Create a Notifier with the given callback. More...
template<typename Arg , typename... Args>
	Notifier (int priority, std::invocable< Arg, Args... > auto &&callback, Arg &&arg, Args &&... args)
	~Notifier ()
	Free the resources for a timer event. More...
	Notifier (Notifier &&rhs)
Notifier &	operator= (Notifier &&rhs)
void	SetName (std::string_view name)
	Sets the name of the notifier. More...
void	SetHandler (std::function< void()> callback)
	Change the callback function. More...
void	SetCallback (std::function< void()> callback)
	Change the callback function. More...
void	StartSingle (units::second_t delay)
	Run the callback once after the given delay. More...
void	StartPeriodic (units::second_t period)
	Run the callback periodically with the given period. More...
void	Stop ()
	Stop further callback invocations. More...

Static Public Member Functions
static bool	SetHALThreadPriority (bool realTime, int32_t priority)
	Sets the HAL notifier thread priority. More...

Detailed Description

Notifiers run a user-provided callback function on a separate thread.

If StartSingle() is used, the callback will run once. If StartPeriodic() is used, the callback will run repeatedly with the given period until stop() is called.

Constructor & Destructor Documentation

Notifier() [1/5]

frc::Notifier::Notifier ( std::function< void()>  callback )

explicit

Create a Notifier with the given callback.

Configure when the callback runs with StartSingle() or StartPeriodic().

Parameters

callback

The callback to run.

Notifier() [2/5]

template<typename Arg , typename... Args>

frc::Notifier::Notifier ( std::invocable< Arg, Args... > auto &&  callback, Arg &&  arg, Args &&...  args  )

inline

Notifier() [3/5]

frc::Notifier::Notifier ( int  priority, std::function< void()>  callback  )

explicit

Create a Notifier with the given callback.

Configure when the callback runs with StartSingle() or StartPeriodic().

This overload makes the underlying thread run with a real-time priority. This is useful for reducing scheduling jitter on processes which are sensitive to timing variance, like model-based control.

Parameters

priority	The FIFO real-time scheduler priority ([1..99] where a higher number represents higher priority). See "man 7 sched" for more details.
callback	The callback to run.

Notifier() [4/5]

template<typename Arg , typename... Args>

frc::Notifier::Notifier ( int  priority, std::invocable< Arg, Args... > auto &&  callback, Arg &&  arg, Args &&...  args  )

inline

~Notifier()

frc::Notifier::~Notifier

(

)

Free the resources for a timer event.

Notifier() [5/5]

frc::Notifier::Notifier

(

Notifier &&

rhs

)

Member Function Documentation

operator=()

Notifier & frc::Notifier::operator=

(

Notifier &&

rhs

)

SetCallback()

void frc::Notifier::SetCallback

(

std::function< void()>

callback

)

Change the callback function.

Parameters

callback

The callback function.

SetHALThreadPriority()

static bool frc::Notifier::SetHALThreadPriority ( bool  realTime, int32_t  priority  )

static

Sets the HAL notifier thread priority.

The HAL notifier thread is responsible for managing the FPGA's notifier interrupt and waking up user's Notifiers when it's their time to run. Giving the HAL notifier thread real-time priority helps ensure the user's real-time Notifiers, if any, are notified to run in a timely manner.

Parameters

realTime	Set to true to set a real-time priority, false for standard priority.
priority	Priority to set the thread to. For real-time, this is 1-99 with 99 being highest. For non-real-time, this is forced to 0. See "man 7 sched" for more details.

Returns

True on success.

SetHandler()

void frc::Notifier::SetHandler

(

std::function< void()>

callback

)

Change the callback function.

Parameters

callback

The callback function.

Deprecated:

Use SetCallback() instead.

SetName()

void frc::Notifier::SetName

(

std::string_view

name

)

Sets the name of the notifier.

Used for debugging purposes only.

Parameters

name

Name

StartPeriodic()

void frc::Notifier::StartPeriodic

(

units::second_t

period

)

Run the callback periodically with the given period.

The user-provided callback should be written so that it completes before the next time it's scheduled to run.

Parameters

period

Period after which to to call the callback starting one period after the call to this method.

StartSingle()

void frc::Notifier::StartSingle

(

units::second_t

delay

)

Run the callback once after the given delay.

Parameters

delay

Time to wait before the callback is called.

Stop()

void frc::Notifier::Stop

(

)

Stop further callback invocations.

No further periodic callbacks will occur. Single invocations will also be cancelled if they haven't yet occurred.

If a callback invocation is in progress, this function will block until the callback is complete.

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

• frc/Notifier.h