Change to custom tick

Bugs
#1

What do you want to achieve?

I have a working SLS project and have just created a new one but now find that LV_TICK_CUSTOM
has changed in lv_conf.h

It used to be:

uint32_t custom_tick_get(void);
#define LV_TICK_CUSTOM 1
#if LV_TICK_CUSTOM
#define LV_TICK_CUSTOM_INCLUDE <stdint.h> /Header for the system time function/
#define LV_TICK_CUSTOM_SYS_TIME_EXPR (custom_tick_get()) /Expression evaluating to current system time in ms/

Now it is:

#define LV_TICK_CUSTOM 1

#if LV_TICK_CUSTOM

#define LV_TICK_CUSTOM_INCLUDE "Arduino.h"         /*Header for the system time function*/

#define LV_TICK_CUSTOM_SYS_TIME_EXPR (millis())    /*Expression evaluating to current system time in ms*/

#endif /LV_TICK_CUSTOM/

Why has this changed ?
In my original code (which the new project code is based on), I have:

/**

  • A callback function that LVGL uses for timing.

  • See LV_TICK_CUSTOM_SYS_TIME_EXPR in lv_conf.h.

  • @return The tick value.

*/

uint32_t custom_tick_get(void)

{

static uint64_t start_ms = 0;

if( start_ms == 0 )

{

    struct timeval tv_start;

    gettimeofday( &tv_start, NULL );

    start_ms = ( tv_start.tv_sec * 1000000 + tv_start.tv_usec ) / 1000;

}

struct timeval tv_now;

gettimeofday( &tv_now, NULL );

uint64_t now_ms;

now_ms = ( tv_now.tv_sec * 1000000 + tv_now.tv_usec ) / 1000;

uint32_t time_ms = now_ms - start_ms;

return time_ms;

}

But now when I run the project I get the following messages appear every second.

[Warn] (0.000, +0) lv_timer_handler: It seems lv_tick_inc() is not called. (in lv_timer.c line #94)

What have you tried so far?

N/A

Screenshot or video

N/A

Others

  • SquareLine Studio version:
    1.0.5
  • Operating system:
    Windows 10 x64
  • Target hardware:
    Raspberry Pi 4

Andy

#2

Okay, so I now call lv_tick_inc(10); in a thread and I no longer get the warnings.
Is this standard practice with LVGL?

Andy

#3

It’s strange because "Arduino.h" is the default header and millis() is the default expr. Custom tick is not enabled by default and we didn’t change it in the exported lv_conf.h. I think you have change it manually.

Your custom_tick_get looks good without lv_tick_inc, you just need to enable it in lv_conf.h. :slightly_smiling_face:

#4

I did enable custom tick in lv_conf.h when I got the “It seems lv_tick_inc() is not called.” message.
I did not notice that the custom tick macro had changed and that it now tries to include “Arduino.h” :frowning:

So what is the correct way to keep LVGL happy?
At present, calling lv_tick_inc in my thread works and I have removed the custom_tick_get function.
Is this the correct way?

Andy

#5

There are 2 options:

  1. Call lv_tick_inc() from a thread or interrupt. Calling it from the main loop also works but it it will result in bad timing as the loop’s period depends on the execution time of lv_timer_handler.
  2. Use a custom function which tells LVGL the elapsed time. It can be configured in lv_conf.h. In this case you don’t need to call lv_tick_inc().

I don’t know what happened with the default config. Do you know in which SLS version you saw custom_tick_get()) as the default value?

#6

I can’t remember when it was - it was before SLS was released and I cloned LVGL from Github.
So how to I do option 2 - I cant set LV_TICK_CUSTOM to 1 in lv_conf.h as that will try and include Arduino.h - what do I need to do in lv_conf.h to allow me to use a custom function such as uint32_t custom_tick_get(void) that I used in my previous project?

Andy