PlatformIO Simulator

I’m new to PlatformIO. My current project which doesnt use LVGL compiles for the Mega and ESP32 no issues.

I tried a simple LVGL “hello world” type app and it compiles/uploads to the ESP32 but I cannot get the Simulator working. Same code doesnt compile.

hello world code below followed by the platformio.ini. I figured I would copy the entry from the GitHub - lvgl/lv_platformio: PlatformIO project example for LVGL, specifically the one for emulator_64bits. I did change the lvgl to be vers 8.3.4 which compiles w/o emulator selected. The demo code below fails on the emulator.

#include <lvgl.h>

void setup() {

lv_obj_t * label = lv_label_create(lv_scr_act());
lv_label_set_text(label, "testing crap");
lv_obj_align(label, LV_ALIGN_CENTER, 0, 0);


void loop() {


platform = espressif32

board = esp32dev

framework = arduino

lib_deps = lvgl/lvgl@^8.3.4


platform = native

extra_scripts = support/

build_flags =



!python -c "import os; print(' '.join(['-I {}'.format(i[0].replace('\x5C','/')) for i in os.walk('hal/sdl2')]))"










-D LV_MEM_SIZE="(128U * 1024U)"

lib_deps = lvgl/lvgl@^8.3.4

build_src_filter =



Error when compiling using emulator_64bits env:

Linking .pio/build/emulator_64bits/program
/usr/bin/ld: /usr/lib/gcc/x86_64-linux-gnu/12/../../../x86_64-linux-gnu/Scrt1.o: in function `_start':
(.text+0x17): undefined reference to `main'
collect2: error: ld returned 1 exit status
*** [.pio/build/emulator_64bits/program] Error 1
  1. I guess the question is, has anyone used PIO IDE with the simulator? Is it as simple as copy the platformio.ini entry and have at it?
  2. Before the simulator, how did you guys write LVGL screens and know where to place stuff?

I’m not that experienced with PIO so can’t really comment on that part. Maybe @puzrin can help. Or you can also ask around in PIO’s forum too.

Before the simulators I tested everything on the target hardware. But it was:

  1. slow to compile and flash every time
  2. hard to debug

Using a simulator is sooo much simpler and convinient.

If I can get it configured for any project, that would be great. Docs are very limited.

lv_platfromio should work with emulator and STM32 too.

I mean, working for Arduino/ESP32 and Teensy. This feature is nice but poorly documented.