Rather, an application that wants to use timers needs to explicitly use the timer library.
The timer library provides functions for setting, resetting and restarting timers, and for checking if a timer has expired. An application must "manually" check if its timers have expired; this is not done automatically.
A timer is declared as a struct
timer
and all access to the timer is made by a pointer to the declared timer.
The timer library uses the Clock library to measure time. Intervals should be specified in the format used by the clock library.
Files | |
file | timer.h |
Timer library header file. | |
file | timer.c |
Timer library implementation. | |
Data Structures | |
struct | timer |
A timer. More... | |
Functions | |
void | timer_set (struct timer *t, clock_time_t interval) |
Set a timer. | |
void | timer_reset (struct timer *t) |
Reset the timer with the same interval. | |
void | timer_restart (struct timer *t) |
Restart the timer from the current point in time. | |
int | timer_expired (struct timer *t) |
Check if a timer has expired. |
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Check if a timer has expired. This function tests if a timer has expired and returns true or false depending on its status.
Definition at line 122 of file timer.c. References clock_time(), interval, and start. Referenced by PROCESS_THREAD(), and PT_THREAD(). |
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Reset the timer with the same interval. This function resets the timer with the same interval that was given to the timer_set() function. The start point of the interval is the exact time that the timer last expired. Therefore, this function will cause the timer to be stable over time, unlike the timer_rester() function.
Definition at line 85 of file timer.c. References interval, and start. Referenced by etimer_reset(), and PROCESS_THREAD(). |
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Restart the timer from the current point in time. This function restarts a timer with the same interval that was given to the timer_set() function. The timer will start at the current time.
Definition at line 105 of file timer.c. References clock_time(), and start. Referenced by etimer_restart(), and PT_THREAD(). |
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Set a timer. This function is used to set a timer for a time sometime in the future. The function timer_expired() will evaluate to true after the timer has expired.
Definition at line 65 of file timer.c. References clock_time(), interval, and start. Referenced by etimer_set(), PROCESS_THREAD(), and tr1001_init(). |