6bd65abbb4
* refactor modules * moved esp_lvgl_port to libs/ * added missing file * fix for sim build * various sim/pc fixes * lvgl improvements * added missing cmake files
32 lines
940 B
Markdown
32 lines
940 B
Markdown
# Tick interface
|
|
|
|
LVGL needs a system tick to know elapsed time for animations and other tasks.
|
|
|
|
You need to call the `lv_tick_inc(tick_period)` function periodically and provide the call period in milliseconds. For example, `lv_tick_inc(1)` when calling every millisecond.
|
|
|
|
`lv_tick_inc` should be called in a higher priority routine than `lv_task_handler()` (e.g. in an interrupt) to precisely know the elapsed milliseconds even if the execution of `lv_task_handler` takes more time.
|
|
|
|
With FreeRTOS `lv_tick_inc` can be called in `vApplicationTickHook`.
|
|
|
|
On Linux based operating systems (e.g. on Raspberry Pi) `lv_tick_inc` can be called in a thread like below:
|
|
```c
|
|
void * tick_thread (void *args)
|
|
{
|
|
while(1) {
|
|
usleep(5*1000); /*Sleep for 5 millisecond*/
|
|
lv_tick_inc(5); /*Tell LVGL that 5 milliseconds were elapsed*/
|
|
}
|
|
}
|
|
```
|
|
|
|
|
|
|
|
## API
|
|
|
|
```eval_rst
|
|
|
|
.. doxygenfile:: lv_hal_tick.h
|
|
:project: lvgl
|
|
|
|
```
|