Taking advantage of great GUI libraries

A project log for gCore - For GUI-based gadgets

An ESP32-based controller board for the Adafruit 3.5" LCD featherwing display designed to serve as the base of portable gadgets.

Dan JulioDan Julio 04/05/2020 at 22:390 Comments

I am a huge fan of  Gábor Kiss-Vámosi's LittlevGL graphics library and, recently, also of Fabrizio Di Vittorio's FabGL for the ESP32.  Check them out if you haven't already.  I have them both running on gCore and will include examples in the github repository.  Currently I plan to release 3 pieces of software for use with gCore.

  1. Arduino power control library - Control power with the ability to power-down from a long-push of the power button, low-battery condition or under control of code.  Monitor battery voltage and charge status.
  2. Code to add display and touchscreen driver for LittlevGL in the arduino environment.  This is in addition to and based on my work supporting the Adafruit display directly in the ESP IDF environment.
  3. Display driver for FabGL.

Currently I have LittlevGL running on the port in the ESP IDF environment and a FabGL driver running in the arduino environment.  The power control library and Arduino LittlevGL module remain vapor-ware at the moment (I just set the HOLD signal high in my current test code and then press the RESET button to power down).

Here are a few teasers of FabGL demos ported over.

The terminal code functions perfectly.  The network terminal lets you log into a telnet server via WiFi.

That lets you stream Star Wars - ASCII style from

Graphics also works but the Space Invaders demo has a bunch of hard-wired code for a lower resolution VGA display and doesn't yet work properly.