If you are looking to update or fix a device with this firmware, keep these community-sourced "best practices" in mind: Format is Key : Use a USB 2.0 drive (not 3.0) formatted to
Firmware acts as the operating system for the hardware. Without the correct version of the HK.T.RT2843P639 firmware, the board may not recognize the specific LCD/LED panel it is connected to, resulting in issues like a "mirror image," inverted colors, or a "hanging" logo.
If you cannot locate the firmware, contact the supplier with your device’s serial number and request the P639 Engineering Release Notes first.