TimesliceRobot extends the TimedRobot robot program framework to provide timeslice scheduling of periodic functions. More...

#include <frc/TimesliceRobot.h>

Inheritance diagram for frc::TimesliceRobot:

Public Member Functions
	TimesliceRobot (units::second_t robotPeriodicAllocation, units::second_t controllerPeriod)
	Constructor for TimesliceRobot. More...

void	Schedule (std::function< void()> func, units::second_t allocation)
	Schedule a periodic function with the constructor's controller period and the given allocation. More...

Public Member Functions inherited from frc::TimedRobot
void	StartCompetition () override
	Provide an alternate "main loop" via StartCompetition(). More...

void	EndCompetition () override
	Ends the main loop in StartCompetition(). More...

	TimedRobot (units::second_t period=kDefaultPeriod)
	Constructor for TimedRobot. More...

	~TimedRobot () override

	TimedRobot (TimedRobot &&)=default

TimedRobot &	operator= (TimedRobot &&)=default

void	AddPeriodic (std::function< void()> callback, units::second_t period, units::second_t offset=0_s)
	Add a callback to run at a specific period with a starting time offset. More...

Public Member Functions inherited from frc::IterativeRobotBase
virtual void	RobotInit ()
	Robot-wide initialization code should go here. More...

virtual void	DriverStationConnected ()
	Code that needs to know the DS state should go here. More...

virtual void	SimulationInit ()
	Robot-wide simulation initialization code should go here. More...

virtual void	DisabledInit ()
	Initialization code for disabled mode should go here. More...

virtual void	AutonomousInit ()
	Initialization code for autonomous mode should go here. More...

virtual void	TeleopInit ()
	Initialization code for teleop mode should go here. More...

virtual void	TestInit ()
	Initialization code for test mode should go here. More...

virtual void	RobotPeriodic ()
	Periodic code for all modes should go here. More...

virtual void	SimulationPeriodic ()
	Periodic simulation code should go here. More...

virtual void	DisabledPeriodic ()
	Periodic code for disabled mode should go here. More...

virtual void	AutonomousPeriodic ()
	Periodic code for autonomous mode should go here. More...

virtual void	TeleopPeriodic ()
	Periodic code for teleop mode should go here. More...

virtual void	TestPeriodic ()
	Periodic code for test mode should go here. More...

virtual void	DisabledExit ()
	Exit code for disabled mode should go here. More...

virtual void	AutonomousExit ()
	Exit code for autonomous mode should go here. More...

virtual void	TeleopExit ()
	Exit code for teleop mode should go here. More...

virtual void	TestExit ()
	Exit code for test mode should go here. More...

void	SetNetworkTablesFlushEnabled (bool enabled)
	Enables or disables flushing NetworkTables every loop iteration. More...

void	EnableLiveWindowInTest (bool testLW)
	Sets whether LiveWindow operation is enabled during test mode. More...

bool	IsLiveWindowEnabledInTest ()
	Whether LiveWindow operation is enabled during test mode. More...

units::second_t	GetPeriod () const
	Gets time period between calls to Periodic() functions. More...

	IterativeRobotBase (units::second_t period)
	Constructor for IterativeRobotBase. More...

	~IterativeRobotBase () override=default

Public Member Functions inherited from frc::RobotBase
bool	IsEnabled () const
	Determine if the Robot is currently enabled. More...

bool	IsDisabled () const
	Determine if the Robot is currently disabled. More...

bool	IsAutonomous () const
	Determine if the robot is currently in Autonomous mode. More...

bool	IsAutonomousEnabled () const
	Determine if the robot is currently in Autonomous mode and enabled. More...

bool	IsTeleop () const
	Determine if the robot is currently in Operator Control mode. More...

bool	IsTeleopEnabled () const
	Determine if the robot is current in Operator Control mode and enabled. More...

bool	IsTest () const
	Determine if the robot is currently in Test mode. More...

bool	IsTestEnabled () const
	Determine if the robot is current in Test mode and enabled. More...

virtual void	StartCompetition ()=0
	Start the main robot code. More...

virtual void	EndCompetition ()=0
	Ends the main loop in StartCompetition(). More...

	RobotBase ()
	Constructor for a generic robot program. More...

virtual	~RobotBase ()=default

Additional Inherited Members
Static Public Member Functions inherited from frc::RobotBase
static std::thread::id	GetThreadId ()
	Gets the ID of the main robot thread. More...

static RuntimeType	GetRuntimeType ()
	Get the current runtime type. More...

static constexpr bool	IsReal ()
	Get if the robot is real. More...

static constexpr bool	IsSimulation ()
	Get if the robot is a simulation. More...

Static Public Attributes inherited from frc::TimedRobot
static constexpr auto	kDefaultPeriod = 20_ms

Protected Member Functions inherited from frc::IterativeRobotBase
	IterativeRobotBase (IterativeRobotBase &&)=default

IterativeRobotBase &	operator= (IterativeRobotBase &&)=default

void	LoopFunc ()

Protected Member Functions inherited from frc::RobotBase
	RobotBase (RobotBase &&)=default

RobotBase &	operator= (RobotBase &&)=default

Static Protected Attributes inherited from frc::RobotBase
static std::thread::id	m_threadId

Detailed Description

TimesliceRobot extends the TimedRobot robot program framework to provide timeslice scheduling of periodic functions.

The TimesliceRobot class is intended to be subclassed by a user creating a robot program.

This class schedules robot operations serially in a timeslice format. TimedRobot's periodic functions are the first in the timeslice table with 0 ms offset and 20 ms period. You can schedule additional controller periodic functions at a shorter period (5 ms by default). You give each one a timeslice duration, then they're run sequentially. The main benefit of this approach is consistent starting times for each controller periodic, which can make odometry and estimators more accurate and controller outputs change more consistently.

Here's an example of measured subsystem durations and their timeslice allocations:

Subsystem	Duration (ms)	Allocation (ms)
Total	5.0	5.0
TimedRobot	?	2.0
Drivetrain	1.32	1.5
Flywheel	0.6	0.7
Turret	0.6	0.8
Free	0.0	N/A

Since TimedRobot periodic functions only run every 20ms, that leaves a 2 ms empty spot in the allocation table for three of the four 5 ms cycles comprising 20 ms. That's OK because the OS needs time to do other things.

If the robot periodic functions and the controller periodic functions have a lot of scheduling jitter that cause them to occasionally overlap with later timeslices, consider giving the main robot thread a real-time priority using frc::SetCurrentThreadPriority(). An RT priority of 15 is a reasonable choice.

If you do enable RT though, make sure your periodic functions do not block. If they do, the operating system will lock up, and you'll have to boot the roboRIO into safe mode and delete the robot program to recover.

Constructor & Destructor Documentation

◆ TimesliceRobot()

frc::TimesliceRobot::TimesliceRobot	(	units::second_t	robotPeriodicAllocation,
		units::second_t	controllerPeriod
	)

explicit

Constructor for TimesliceRobot.

Parameters

robotPeriodicAllocation	The allocation to give the TimesliceRobot periodic functions.
controllerPeriod	The controller period. The sum of all scheduler allocations should be less than or equal to this value.

Member Function Documentation

◆ Schedule()

void frc::TimesliceRobot::Schedule	(	std::function< void()>	func,
		units::second_t	allocation
	)

Schedule a periodic function with the constructor's controller period and the given allocation.

The function's runtime allocation will be placed after the end of the previous one's.

If a call to this function makes the allocations exceed the controller period, an exception will be thrown since that means the TimesliceRobot periodic functions and the given function will have conflicting timeslices.

Parameters

func	Function to schedule.
allocation	The function's runtime allocation out of the controller period.

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

frc/TimesliceRobot.h

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ TimesliceRobot()

Member Function Documentation

◆ Schedule()