This group of functions provides a one shot timer implemenation.
It is inspired by Jörg Wunschs timer implementation, which can be found here: http://sax.sax.de/~joerg/avr-timer/
Data Structures | |
struct | time_stamp_tag |
Defines | |
#define | MSEC(v) ((time_t)(v / (1.0e3 * TIMER_TICK))) |
#define | USEC(v) ((time_t)(v / (1.0e6 * TIMER_TICK))) |
Typedefs | |
typedef struct time_stamp_tag | time_stamp_t |
typedef uint32_t | time_t |
typedef uint32_t | timer_arg_t |
typedef time_t( | timer_handler_t )(timer_arg_t p) |
typedef uint16_t | timer_hdl_t |
Functions | |
void | timer_init (void) |
Initialization of the timer module. | |
timer_hdl_t | timer_restart (timer_hdl_t th, time_t duration) |
Restarting a running timer. | |
void | timer_set_systime (time_t sec) |
Set the current system time given in seconds since 1.1.1970. | |
timer_hdl_t | timer_start (timer_handler_t *thfunc, time_t duration, timer_arg_t arg) |
Start a timer with a given handler function. | |
timer_hdl_t | timer_stop (timer_hdl_t th) |
Stop a running timer. | |
time_t | timer_systime (void) |
Return the current system time in ticks. |
#define MSEC | ( | v | ) | ((time_t)(v / (1.0e3 * TIMER_TICK))) |
#define USEC | ( | v | ) | ((time_t)(v / (1.0e6 * TIMER_TICK))) |
typedef uint32_t time_t |
typedef uint32_t timer_arg_t |
typedef time_t( timer_handler_t)(timer_arg_t p) |
Data type for timer expiration action function. This function is called, when the expiration time is over. When luanched, the function is called with a parameter p of type .timer_arg_t. If the function returns a value, which is greate then 0, the timer is restarted again.
typedef uint16_t timer_hdl_t |
void timer_init | ( | void | ) |
Initialization of the timer module.
timer_hdl_t timer_restart | ( | timer_hdl_t | th, | |
time_t | duration | |||
) |
Restarting a running timer.
If the timer is found in the timer queue, then it is rstarted with the new duration value.
th | Handle of the timer. The timer needs to exist in the timer queue, e.g. it is started with timer_start() and not yet expired. | |
duration | time in system ticks from now, when the timer expires. |
void timer_set_systime | ( | time_t | sec | ) |
Set the current system time given in seconds since 1.1.1970.
timer_hdl_t timer_start | ( | timer_handler_t * | thfunc, | |
time_t | duration, | |||
timer_arg_t | arg | |||
) |
Start a timer with a given handler function.
This function initially creates a timer and assigns a timer handle to it. The timer handle is reference number, which identifies the timer uniquely and is needed for restart and stop a running timer.
thfunc | pointer to a function, which is called when the timer expires. | |
duration | time in system ticks from now, when the timer expires. | |
arg | argument, which is passed to the timer function. |
timer_hdl_t timer_stop | ( | timer_hdl_t | th | ) |
Stop a running timer.
th | Handle of the timer. The timer needs to exist in the timer queue, e.g. it is started with timer_start() and not yet expired. |
time_t timer_systime | ( | void | ) |
Return the current system time in ticks.