Clock and Timer Management

Collaboration diagram for Clock and Timer Management:

Data Structures
struct	rt_timer

Macros
#define	RT_TIMER_FLAG_DEACTIVATED   0x0
#define	RT_TIMER_FLAG_ACTIVATED   0x1
#define	RT_TIMER_FLAG_ONE_SHOT   0x0
#define	RT_TIMER_FLAG_PERIODIC   0x2
#define	RT_TIMER_FLAG_HARD_TIMER   0x0
#define	RT_TIMER_FLAG_SOFT_TIMER   0x4
#define	RT_TIMER_FLAG_THREAD_TIMER    (0x8 | RT_TIMER_FLAG_HARD_TIMER)
#define	RT_TIMER_CTRL_SET_TIME   0x0
#define	RT_TIMER_CTRL_GET_TIME   0x1
#define	RT_TIMER_CTRL_SET_ONESHOT   0x2
#define	RT_TIMER_CTRL_SET_PERIODIC   0x3
#define	RT_TIMER_CTRL_GET_STATE   0x4
#define	RT_TIMER_CTRL_GET_REMAIN_TIME   0x5
#define	RT_TIMER_CTRL_GET_FUNC   0x6
#define	RT_TIMER_CTRL_SET_FUNC   0x7
#define	RT_TIMER_CTRL_GET_PARM   0x8
#define	RT_TIMER_CTRL_SET_PARM   0x9
#define	RT_TIMER_SKIP_LIST_MASK   0x3

Typedefs
typedef void(*	rt_timer_func_t) (void *parameter)

Functions
rt_tick_t	rt_tick_get (void)
void	rt_tick_set (rt_tick_t tick)
void	rt_tick_increase (void)
void	rt_tick_increase_tick (rt_tick_t tick)
rt_tick_t	rt_tick_from_millisecond (rt_int32_t ms)
rt_weak rt_tick_t	rt_tick_get_millisecond (void)
void	rt_timer_init (rt_timer_t timer, const char *name, void(*timeout)(void *parameter), void *parameter, rt_tick_t time, rt_uint8_t flag)
rt_err_t	rt_timer_detach (rt_timer_t timer)
rt_timer_t	rt_timer_create (const char *name, void(*timeout)(void *parameter), void *parameter, rt_tick_t time, rt_uint8_t flag)
rt_err_t	rt_timer_delete (rt_timer_t timer)
rt_err_t	rt_timer_start (rt_timer_t timer)
rt_err_t	rt_timer_stop (rt_timer_t timer)
rt_err_t	rt_timer_control (rt_timer_t timer, int cmd, void *arg)
void	rt_timer_check (void)
rt_tick_t	rt_timer_next_timeout_tick (void)
void	rt_system_timer_init (void)
void	rt_system_timer_thread_init (void)

Detailed Description

clock and system timer management

RT-Thread uses clock tick to implement shared time-slice scheduling.

The timing sensitivity of thread is implemented by timers. The timer can be set as one-shot or periodic timeout.

Macro Definition Documentation

RT_TIMER_FLAG_DEACTIVATED

#define RT_TIMER_FLAG_DEACTIVATED   0x0

clock & timer macros timer is deactive

RT_TIMER_FLAG_ACTIVATED

#define RT_TIMER_FLAG_ACTIVATED   0x1

timer is active

RT_TIMER_FLAG_ONE_SHOT

#define RT_TIMER_FLAG_ONE_SHOT   0x0

one shot timer

RT_TIMER_FLAG_PERIODIC

#define RT_TIMER_FLAG_PERIODIC   0x2

periodic timer

RT_TIMER_FLAG_HARD_TIMER

#define RT_TIMER_FLAG_HARD_TIMER   0x0

hard timer,the timer's callback function will be called in tick isr.

RT_TIMER_FLAG_SOFT_TIMER

#define RT_TIMER_FLAG_SOFT_TIMER   0x4

soft timer,the timer's callback function will be called in timer thread.

RT_TIMER_FLAG_THREAD_TIMER

#define RT_TIMER_FLAG_THREAD_TIMER    (0x8 | RT_TIMER_FLAG_HARD_TIMER)

thread timer that cooperates with scheduler directly

RT_TIMER_CTRL_SET_TIME

#define RT_TIMER_CTRL_SET_TIME   0x0

set timer control command

RT_TIMER_CTRL_GET_TIME

#define RT_TIMER_CTRL_GET_TIME   0x1

get timer control command

RT_TIMER_CTRL_SET_ONESHOT

#define RT_TIMER_CTRL_SET_ONESHOT   0x2

change timer to one shot

RT_TIMER_CTRL_SET_PERIODIC

#define RT_TIMER_CTRL_SET_PERIODIC   0x3

change timer to periodic

RT_TIMER_CTRL_GET_STATE

#define RT_TIMER_CTRL_GET_STATE   0x4

get timer run state active or deactive

RT_TIMER_CTRL_GET_REMAIN_TIME

#define RT_TIMER_CTRL_GET_REMAIN_TIME   0x5

get the remaining hang time

RT_TIMER_CTRL_GET_FUNC

#define RT_TIMER_CTRL_GET_FUNC   0x6

get timer timeout func

RT_TIMER_CTRL_SET_FUNC

#define RT_TIMER_CTRL_SET_FUNC   0x7

set timer timeout func

RT_TIMER_CTRL_GET_PARM

#define RT_TIMER_CTRL_GET_PARM   0x8

get timer parameter

RT_TIMER_CTRL_SET_PARM

#define RT_TIMER_CTRL_SET_PARM   0x9

get timer parameter

RT_TIMER_SKIP_LIST_MASK

#define RT_TIMER_SKIP_LIST_MASK   0x3

Timer skips the list mask

Typedef Documentation

rt_timer_func_t

typedef void(* rt_timer_func_t) (void *parameter)

timeout handler of rt_timer

Function Documentation

rt_tick_get()

rt_tick_t rt_tick_get

(

void

)

This function will return current tick from operating system startup.

Returns

Return current tick.

rt_tick_set()

void rt_tick_set

(

rt_tick_t

tick

)

This function will set current tick.

Parameters

tick	is the value that you will set.

rt_tick_increase()

void rt_tick_increase

(

void

)

This function will notify kernel there is one tick passed. Normally, this function is invoked by clock ISR.

rt_tick_increase_tick()

void rt_tick_increase_tick

(

rt_tick_t

tick

)

This function will notify kernel there is n tick passed. Normally, this function is invoked by clock ISR.

rt_tick_from_millisecond()

rt_tick_t rt_tick_from_millisecond

(

rt_int32_t

ms

)

This function will calculate the tick from millisecond.

Parameters

ms	is the specified millisecond. Negative Number wait forever Zero not wait Max 0x7fffffff

Returns

Return the calculated tick.

rt_tick_get_millisecond()

rt_tick_t rt_tick_get_millisecond

(

void

)

This function will return the passed millisecond from boot.

Note

if the value of RT_TICK_PER_SECOND is lower than 1000 or is not an integral multiple of 1000, this function will not provide the correct 1ms-based tick.

Returns

Return passed millisecond from boot.

rt_timer_init()

void rt_timer_init	(	rt_timer_t	timer,
		const char *	name,
		void(*)(void *parameter)	timeout,
		void *	parameter,
		rt_tick_t	time,
		rt_uint8_t	flag
	)

This function will initialize a timer normally this function is used to initialize a static timer object.

Parameters

timer	is the point of timer
name	is a pointer to the name of the timer
timeout	is the callback of timer
parameter	is the param of the callback
time	is timeout ticks of timer NOTE: The max timeout tick should be no more than (RT_TICK_MAX/2 - 1).
flag	is the flag of timer

rt_timer_detach()

rt_err_t rt_timer_detach

(

rt_timer_t

timer

)

This function will detach a timer from timer management.

Parameters

timer

is the timer to be detached

Returns

the status of detach

rt_timer_create()

rt_timer_t rt_timer_create	(	const char *	name,
		void(*)(void *parameter)	timeout,
		void *	parameter,
		rt_tick_t	time,
		rt_uint8_t	flag
	)

This function will create a timer.

Parameters

name	is the name of timer
timeout	is the timeout function
parameter	is the parameter of timeout function
time	is timeout ticks of the timer NOTE: The max timeout tick should be no more than (RT_TICK_MAX/2 - 1).
flag	is the flag of timer. Timer will invoke the timeout function according to the selected values of flag, if one or more of the following flags is set. RT_TIMER_FLAG_ONE_SHOT One shot timing RT_TIMER_FLAG_PERIODIC Periodic timing RT_TIMER_FLAG_HARD_TIMER Hardware timer RT_TIMER_FLAG_SOFT_TIMER Software timer RT_TIMER_FLAG_THREAD_TIMER Thread timer NOTE: You can use multiple values with "|" logical operator. By default, system will use the RT_TIME_FLAG_HARD_TIMER.

Returns

the created timer object

rt_timer_delete()

rt_err_t rt_timer_delete

(

rt_timer_t

timer

)

This function will delete a timer and release timer memory.

Parameters

timer

the timer to be deleted

Returns

the operation status, RT_EOK on OK; -RT_ERROR on error

rt_timer_start()

rt_err_t rt_timer_start

(

rt_timer_t

timer

)

This function will start the timer.

Parameters

timer

the timer to be started

Returns

the operation status, RT_EOK on OK, -RT_ERROR on error

rt_timer_stop()

rt_err_t rt_timer_stop

(

rt_timer_t

timer

)

This function will stop the timer.

Parameters

timer

the timer to be stopped

Returns

the operation status, RT_EOK on OK, -RT_ERROR on error

rt_timer_control()

rt_err_t rt_timer_control	(	rt_timer_t	timer,
		int	cmd,
		void *	arg
	)

This function will get or set some options of the timer.

Parameters

timer	the timer to be get or set
cmd	the control command
arg	the argument

Returns

the statu of control

rt_timer_check()

void rt_timer_check

(

void

)

This function will check timer list, if a timeout event happens, the corresponding timeout function will be invoked.

Note

This function shall be invoked in operating system timer interrupt.

rt_timer_next_timeout_tick()

rt_tick_t rt_timer_next_timeout_tick

(

void

)

This function will return the next timeout tick in the system.

Returns

the next timeout tick in the system

rt_system_timer_init()

void rt_system_timer_init

(

void

)

This function will initialize system timer.

rt_system_timer_thread_init()

void rt_system_timer_thread_init

(

void

)

This function will initialize system timer thread.