43 lines
1.1 KiB
Markdown
43 lines
1.1 KiB
Markdown
```eval_rst
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.. include:: /header.rst
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:github_url: |github_link_base|/porting/timer-handler.md
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```
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# Timer Handler
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To handle the tasks of LVGL you need to call `lv_timer_handler()` periodically in one of the following:
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- *while(1)* of *main()* function
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- timer interrupt periodically (lower priority than `lv_tick_inc()`)
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- an OS task periodically
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The timing is not critical but it should be about 5 milliseconds to keep the system responsive.
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Example:
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```c
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while(1) {
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lv_timer_handler();
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my_delay_ms(5);
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}
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```
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If you want to use `lv_timer_handler()` in a super-loop, a helper function`lv_timer_handler_run_in_period()` is provided to simplify the porting:
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```c
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while(1) {
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...
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lv_timer_handler_run_in_period(5); /* run lv_timer_handler() every 5ms */
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...
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}
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```
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In an OS environment, you can use it together with the **delay** or **sleep** provided by OS to release CPU whenever possible:
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```c
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while (1) {
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lv_timer_handler_run_in_period(5); /* run lv_timer_handler() every 5ms */
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my_delay_ms(5); /* delay 5ms to avoid unnecessary polling */
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}
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```
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To learn more about timers visit the [Timer](/overview/timer) section.
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