Look for a file typically named allupgrade_5510_8G_1G.bin (or similar).
: A common repository for Shivaki-specific firmware and board software. Download File TP-MT5510S-PB802-1G-8G-HD-SHIVAKI...
For general settings or resets, try standard factory codes like Menu + 1147 or Source + 2580 . Look for a file typically named allupgrade_5510_8G_1G