If this is from a device (suggested by the "Tp." prefix), please check the full model number on the product label (e.g., Archer C6 , TL-WR841N , etc.) and download drivers/firmware directly from TP-Link's official support site .
Firmware for this specific board is usually found on specialized technician repositories rather than a single official consumer site.
(found on a sticker on the back of the LCD panel itself). Ensure the firmware you download matches the resolution
: Look for "stock firmware" or "ROM" packages for the TP.SK518D.PC821
Another technician-focused blog that provides direct links to many universal board firmwares. Installation Steps (USB Method) Format your USB drive: Use a drive 8GB or smaller and format it to Copy the file: Place the downloaded firmware file (usually named allupgrade_518_sos.bin or similar) into the root directory of the USB. Do not put it in a folder. Turn off the TV and unplug the power cord. Insert the USB drive into the TV's USB port. Plug the TV back in.
Once the flashing stops or the TV reboots, the process is complete. Critical Warning Before flashing, verify your Panel Model Number