The "1366x768" in your query refers to the specific display resolution of the panel the firmware is intended for.
The file refers to a firmware package for the (often model T.RD8503.03 or T.RD8503.A8
Power on the board. A light on the keypad or board will typically begin flashing (often red and green or rapidly blinking red).
If you are planning to flash this firmware, the general procedure involves using a USB drive formatted to .
The .rar file is a compressed archive that typically contains:
Once the light stops flashing or stays solid, the update is finished. You must power off the board before removing the USB drive. Technical Warnings
Place the .bin file in the root directory of the USB flash drive (do not put it in a folder). Execution: Insert the USB drive into the board while it is powered off.
The core firmware, often named something like SKR8503_100.bin or T.RD8503.bin .