Hardare timer peripheral support. More...

Detailed Description

Hardare timer peripheral support.

Supports general-function TIM peripherals:

TIM2, TIM3, TIM4, TIM5

DaisySeed, and many internal peripherals utilize TIM2 for timing/delay purposes. It is configured to be at the maximum frequency: typically 200MHz or 240MHz (boost) for measuring/delaying for very short periods.

The GetUs/GetMs functions are available for convenience (and backwards compatibility), but to avoid wrapping errors on math when doing time-delta calculations, using ticks is recommended. The data can be converted to the final time-base after getting the difference in ticks. (Using GetFreq() can be used for these time-base calculations).

User callbacks can be set, and changed at any point during operation. However, the Config::enable_irq must be set to true when initializing for the interrupts to turn on and function.

Todo:

Fix issues with realtime getters, and wrapping of the timer(s).

This very noticeable with default settings for the 16-bit counters.

Other General purpose timers

Non-internal clock sources

Use of the four-tim channels per tim

PWM, etc.
InputCapture/OutputCompare, etc.

HRTIM

Advanced timers (TIM1/TIM8)

#include <tim.h>

Classes
struct	Config
	Configuration struct for the Peripheral. More...

Public Types
enum class	Result { OK , ERR }
	Return values for TIM funcitons. More...

typedef void(*	PeriodElapsedCallback) (void *data)
	User Callback type that will fire at the end of each timer period. This requires that Config::enable_irq is true before Init.

Public Member Functions
	TimerHandle ()

	TimerHandle (const TimerHandle &other)=default

TimerHandle &	operator= (const TimerHandle &other)=default

	~TimerHandle ()

Result	Init (const Config &config)
	Initializes the timer according to the configuration.

Result	DeInit ()
	Deinitializes the timer.

const Config &	GetConfig () const
	Returns a const reference to the Config struct.

Result	SetPeriod (uint32_t ticks)
	Sets the period of the Timer.

Result	SetPrescaler (uint32_t val)
	Sets the Prescalar applied to the TIM peripheral.

Result	Start ()
	Starts the TIM peripheral specified by Config.

Result	Stop ()
	Stops the TIM peripheral specified by Config.

uint32_t	GetFreq ()
	Returns the frequency of each tick of the timer in Hz.

uint32_t	GetTick ()
	Returns the number of counter position.

uint32_t	GetMs ()
	Returns the ticks scaled as milliseconds.

uint32_t	GetUs ()
	Returns the ticks scaled as microseconds.

void	DelayTick (uint32_t del)
	Stay within this function for del ticks.

void	DelayMs (uint32_t del)
	Stay within this function for del milliseconds.

void	DelayUs (uint32_t del)
	Stay within this function for del microseconds.

void	SetCallback (PeriodElapsedCallback cb, void *data=nullptr)
	Sets the PeriodElapsedCallback that will fire whenever the timer reaches the end of it's period.

Member Typedef Documentation

◆ PeriodElapsedCallback

typedef void(* daisy::TimerHandle::PeriodElapsedCallback) (void *data)

User Callback type that will fire at the end of each timer period. This requires that Config::enable_irq is true before Init.

Parameters

data	pointer to arbitrary user-provided data

Member Enumeration Documentation

◆ Result

enum class daisy::TimerHandle::Result

strong

Return values for TIM funcitons.

Enumerator
OK
ERR

Constructor & Destructor Documentation

◆ TimerHandle() [1/2]

daisy::TimerHandle::TimerHandle ( )

inline

◆ TimerHandle() [2/2]

daisy::TimerHandle::TimerHandle ( const TimerHandle & other )

default

◆ ~TimerHandle()

daisy::TimerHandle::~TimerHandle ( )

inline

Member Function Documentation

◆ DeInit()

Result daisy::TimerHandle::DeInit ( )

Deinitializes the timer.

◆ DelayMs()

void daisy::TimerHandle::DelayMs ( uint32_t del )

Stay within this function for del milliseconds.

◆ DelayTick()

void daisy::TimerHandle::DelayTick ( uint32_t del )

Stay within this function for del ticks.

◆ DelayUs()

void daisy::TimerHandle::DelayUs ( uint32_t del )

Stay within this function for del microseconds.

◆ GetConfig()

const Config & daisy::TimerHandle::GetConfig ( ) const

Returns a const reference to the Config struct.

◆ GetFreq()

uint32_t daisy::TimerHandle::GetFreq ( )

Returns the frequency of each tick of the timer in Hz.

◆ GetMs()

uint32_t daisy::TimerHandle::GetMs ( )

Returns the ticks scaled as milliseconds.

Use care when using for measurements and ensure that the TIM period can handle the maximum desired measurement.

◆ GetTick()

uint32_t daisy::TimerHandle::GetTick ( )

Returns the number of counter position.

This increments according to Config::CounterDir, and wraps around at the specified period (maxing out at 2^16 or 2^32 depending on the chosen TIM peripheral.

◆ GetUs()

uint32_t daisy::TimerHandle::GetUs ( )

Returns the ticks scaled as microseconds.

Use care when using for measurements and ensure that the TIM period can handle the maximum desired measurement.

◆ Init()

Result daisy::TimerHandle::Init ( const Config & config )

Initializes the timer according to the configuration.

◆ operator=()

TimerHandle & daisy::TimerHandle::operator= ( const TimerHandle & other )

default

◆ SetCallback()

void daisy::TimerHandle::SetCallback	(	PeriodElapsedCallback	cb,
		void *	data = `nullptr`
	)

Sets the PeriodElapsedCallback that will fire whenever the timer reaches the end of it's period.

Parameters

cb	user callback
data	optional pointer to arbitrary data (defaults to nullptr)

◆ SetPeriod()

Result daisy::TimerHandle::SetPeriod ( uint32_t ticks )

Sets the period of the Timer.

This is the number of ticks it takes before it wraps back around. For self-managed timing, this can be left at the default. (0xffff for 16-bit and 0xffffffff for 32-bit timers). This can be changed "on-the-fly"

◆ SetPrescaler()

Result daisy::TimerHandle::SetPrescaler ( uint32_t val )

Sets the Prescalar applied to the TIM peripheral.

This can be any number up to 0xffff This will adjust the rate of ticks: Calculated as APBN_Freq / prescalar per tick where APBN is APB1 for Most general purpose timers, and APB2 for HRTIM,a nd the advanced timers. This can be changed "on-the-fly"

◆ Start()

Result daisy::TimerHandle::Start ( )

Starts the TIM peripheral specified by Config.

◆ Stop()

Result daisy::TimerHandle::Stop ( )

Stops the TIM peripheral specified by Config.

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

src/per/tim.h