PCSX2 expects or a folder with ROMs. For a USA V12 console:
. This specific BIOS version (v12) is historically significant because it belongs to the first generation of "Slimline" consoles. Key Features and Context Console Compatibility : This BIOS is designed for the V12/V13 hardware revision scph-70012-bios-v12-usa-200.bin
The V12 BIOS was the first to fully implement RCE 2.0 (Regional Code Enhancement). This was Sony’s aggressive response to the "Independence Exploit" (the 2003 hack using modified save files). The 200.bin dump is notable because it bypasses early soft-modding checks present in V1 of the BIOS. PCSX2 expects or a folder with ROMs