LCD backlight test

This program only turns on the LCD backlight GPIO.

It does not initialize SPI. It does not initialize the LCD controller. It does not write any pixel data.

Set LCD_PIN_BL to the GPIO connected to the LCD BLK pin. Set LCD_BL_ACTIVE_HIGH to match the board.

Build and flash:

idf.py menuconfig
idf.py build
idf.py -p COMx flash

Expected result: the LCD backlight turns on and stays on.

Update image data

Use this script to generate main/eye_image.c and main/eye_image.h from an image or GIF:

C:\Users\28036\.cache\codex-runtimes\codex-primary-runtime\dependencies\python\python.exe D:\esp\Project\lcd\tools\gif_to_eye_image.py D:\esp\Project\lcd\source\eye2.bmp

For GIF files, use --max-frames or --step if the generated file is too large.