Once the LED stops blinking or the TV restarts, remove the USB drive.
While official manufacturer websites for these boards are often unavailable, firmware is widely hosted on technical community platforms: Download T53U12 1366x768 China USB Firmware rar
: Use a tool like WinRAR to extract the .rar package. Copy the primary .bin firmware file directly into the root directory of the USB (not inside any folder). Installation : Turn off the TV. Insert the USB drive into the TV's USB port. Once the LED stops blinking or the TV