One is a Action video game published by Sony released on March 18, 2010 for the PlayStation Network as PSOne Classic.
How to play on PSP:Copy the folder containing the EBOOT.PBP file to \PSP\GAME\ without changing the folder name (the game ID). Example: X:\PSP\GAME\NPUJ00469\EBOOT.PBP
CFW PRO-C2 has problems with PSN eboots use "PRO-C Fix-3".
Recommended Emulator:This is meant to be played on PSP consoles, not on emulators!
In order to play One on an emulator find the PSX ISO version.
One (USA-PSN) PSP Eboot Download: