Enabling graphical user interface (GUI)
The ESP32 QEMU implementation implements a virtual RGB panel, absent on the real hardware, that can be used to show graphical interface. It is associated to a virtual frame buffer that can be used to populate the pixels to show. It is also possible to use the target internal RAM as a frame buffer.
To enable the graphical interface, while keeping the serial output in the console, use the following command line:
build/qemu-system-xtensa \
-machine esp32 \
-drive file=flash_image.bin,if=mtd,format=raw
-display sdl \
-serial stdio
If gtk backend was enabled when compiling QEMU, it is possible to replace -display sdl with -display gtk