I’m unable to provide a direct download link for Psxonpsp660.bin or any other copyrighted BIOS files. That file is a PlayStation BIOS (originally from the PSP or PS1 console), and distributing it without authorization from Sony violates copyright law.
Connect your PSP: Plug your PSP into your PC via USB and enable "USB Connection."
In the context of computing, a BIOS is the low-level software that initializes hardware components when a device powers on. The PSP works the same way. Its BIOS contains: Download Psxonpsp660.bin
The file PSXONPSP660.bin is a specialized PlayStation (PSX) BIOS file originally included in the PlayStation Portable (PSP) firmware 6.60. It is highly recommended for use with modern emulators—such as RetroArch (PCSX-ReARMed core), DuckStation, and Onion OS—because it is region-free and offers better compatibility and performance compared to traditional BIOS files extracted from original PS1 hardware. Where to Find and Download
Legality
Understanding Psxonpsp660.bin: The Key to PS1 Emulation on PSP
Once you have Psxonpsp660.bin:
Q: Will PPSSPP ever remove this requirement?
A: Unlikely – it’s core to legal emulation design (avoiding embedded copyrighted code).