If your board still shows a USB drive activity light but the screen is scrambled or the OSD won’t appear, you can use the USB port.
GENERIC CHINA LED TV TP. VST59S. PB813 SCH Service Manual download, schematics, eeprom, repair info for electronics experts. Elektrotanya Tp.vst59s.pb813 Firmware Mirror
Some firmware mirrors disable certain inputs. You need a mirror compiled for "multiple inputs". Check your source for notes like HDMI+VGA+AV vs VGA only . If your board still shows a USB drive
When dealing with this universal TV main board (often used in LCD/LED monitor conversions or TV repairs), a useful feature to implement in a firmware tool or guide would be: Tp.vst59s.pb813 Firmware Mirror
Use a USB 2.0 drive formatted to FAT32 .