Problem within LVGL and a thirs-party lib?

I have a bothering problem by using the T-RGB (both full-circle-versions) together with SLS/LVGL and a Wi-Fi-Lib called ESPAsyncWiFiManager (GitHub - khoih-prog/ESPAsync_WiFiManager: This is an ESP32 (including ESP32-S2 and ESP32-C3) / ESP8266 WiFi Connection Manager, using ESPAsyncWebServer, with fallback web configuration portal. Use this library for configuring ESP32, ESP8266 modules' WiFi, etc. Credentials at runtime. You can also specify static DNS servers, personalized HostName, fixed or random AP WiFi channel. With examples supporting ArduinoJson 6.0.0+ as well as 5.13.5- . Using AsyncDNSServer instead of DNSServer now.)

I cannot find out if the is a fault from the Lib, from LVGL or the T-RGB at last, maybe somebody has an idea what might cause this problem. I already have posted this problem in different ESP32 forums without feedback, and the repository of the lib is set to read-only by the author, therefore the related issue forum is close. The author does not reply to inquiries.

I am using the lib “ESPAsyncWiFimanager” to handle all WiFi-related issues, which works very satisfactorily and is very well documented, except for one annoying thing:

From the moment the class “ESPAsyncWiFimanager” is instantiated in the code, and until the moment a WiFi connection has been established (or the timeout of three minutes occurs), no screen output via LVGL is possible, despite the output made in the code (incl. LV_task_handler() invoked), the display remains black. Since it makes sense to initialize the class as a global variable in the top-level main model, it is not possible to output any user instructions for establishing the WiFi connection, such as specifying the WiFi credentials for the activated config portal on the cell phone. This is very annoying as the user must stare more or less helplessly at a black screen for three minutes until the timeout.

I have inspected most of the code, but do not find any issues which causes this behavior. And therefore, I do not know if this is fault of the lib, or it might be caused by an interference between T-RGB, LVGL and the lib.
Any ideas?


  • **SquareLine Studio version:1.3.4
  • **Operating system: WIN 11
  • **Target hardware: ESP32-S3 LilyGo T-RGB Module (all versions)