: In your upgrade tool (like GXDownloader ), confirm the following settings: Port : Correct COM port assigned to your adapter. Baud Rate : Typically 115200.
For specific firmware files and loaders, you can check community resources like LemmyMorgan's Gsky V8 Guide for step-by-step instructions. Are you using a USB-to-TTL adapter or a standard RS232 cable for this connection? bootrom error wait for get please check stb uart receive hot