Ya it's used to load ps1 game eboots without needing to use keys.bin files, I assumed someone on this forum uses it lol ;)
Well i could explain but its very simpel,.. ;)
POPS is ps1 emulator on the psp,..
POPS sometimes changes with a new firmware release,. new update's in the pops menu,.. when you run a PS1 game and press "home"
Here is a little tut i made on my "eboot pack topic"
Also explains why you had keys.bin files,..
Spoiler for tutroriol:
Here is a "How to" if you want to convert a already converted game(eboot.pbp en ev keys.bin) ,
or a PS1 back-up game(.iso, .img, .cue, ..)
For PS1 back-up games, all steps are the same except for "recompress" wich you do not use!
If you have 3.03oeb you use popstation gui 2,26
If you have 3.03oec 3.10oe etc. you use Zingaburga's Popstaion Gui 3.00
-Download one of my Eboot Packs voor the game you have.
-(Unpack: -WinRar save somewhere on your computer.)
-Start ZinGaBurga Popstaion Gui
-Load the Eboot.pbp OR an .iso/.cue/.img files.
-Click Recompress,(Only when you use anEboot.pbp file)
-Put compress to 5.(It compresses the new Eboot for more space on your Mem Stick)
-OUTPUT Folder: Create a new folder with name of the game.
-Select "Game ID" From the list(game_title)
-If you have 3.10oe+(and its popstation)you do not need the NTSC patch.
-If you have 3.03oeb(and its popstation) you click "Pal to NTSC" patch.
-And now: click "Customize the Eboot"
-And first of all unclick: SND.at3(You do not need these)!!
-Now you can add my files wich you saved somewhere on your computer:ICON0.png, PIC1.png, ICON1.pmf, gameboot.png
-(Click op Preview)
En click on "GO"
Did you use ZiNgABuRgA's Popstaion Gui 2.26 then you have eboot.pbp and keys.bin
Did you use ZiNgABuRgA's Popstation Gui 3.00 then you only have eboot.pbp
The eboot.pbp "and/or not" keys.bin files are paced in a folder(name of the game)
And that folder goes in :/psp/game on your memory stick
That's it
Now pops loader plugin works great for games wich need a earlier released pops then the firmware you have installed,.
With pops loader plugin you can hold right trigger when starting a ps1 game and then you get a small menu from wich you can select the pops you want to use,. or choose the pops from flash0,..