blob: 1a40a62f742a475ad11fdf810741002c84e69b60 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
.. _timer:
=============
Timer Handler
=============
To handle the tasks of LVGL you need to call :cpp:func:`lv_timer_handler`
periodically in one of the following:
- *while(1)* of *main()* function
- timer interrupt periodically (lower priority than :cpp:func:`lv_tick_inc`)
- an OS task periodically
Example:
.. code:: c
while(1) {
uint32_t time_till_next = lv_timer_handler();
my_delay_ms(time_till_next);
}
If you want to use :cpp:func:`lv_timer_handler` in a super-loop, a helper
function :cpp:func:`lv_timer_handler_run_in_period` is provided to simplify
the porting:
.. code:: c
while(1) {
...
lv_timer_handler_run_in_period(5); /* run lv_timer_handler() every 5ms */
...
}
Or use the sleep time automatically calculated by LVGL:
.. code:: c
while(1) {
...
lv_timer_periodic_handler();
...
}
In an OS environment, you can use it together with the **delay** or
**sleep** provided by OS to release CPU whenever possible:
.. code:: c
while (1) {
uint32_t time_till_next = lv_timer_handler();
os_delay_ms(time_till_next); /* delay to avoid unnecessary polling */
}
To learn more about timers visit the :ref:`timer`
section.
API
***
|
