PSXONPSP660.bin is a high-performance (Basic Input/Output System) file used for PlayStation 1 (PS1)
In the core options for or Beetle PSX , ensure the BIOS path is set to point to this file. Anbernic (RG35XX / ArkOS) : download psxonpsp660bin top
BIOS files are copyrighted system software owned by Sony. You should legally only obtain this file by extracting it from your own Sony PSP firmware. If you'd like, I can: PSXONPSP660