If you're looking to cheat whatever PSP game for whatever your reason(s), then look no further than DarkFrost. It's a [semi-]actively maintained cheat engine (read: plugin) for the PSP from developer, and Dashhacks forum member, demon450.
DarkFrost is a mod of SANiK's NitePR Rev. J. This version -- DarkFrost v5 -- is a maintenance release, which fixes many bugs and tidies things up a bit. It also comes with an auto-installer for ease of installation ... but as always see README.txt for important notes.
As for the actual PSP cheat codes -- use Google ... or Codeleakers is a good place to start for NitePR codes, which are of course DarkFrost compatible.
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