Memory Stick file tree

The PSP uses memory sticks for reading and writing various types of data. By using a USB cable, or a memory stick writer for your computer, you can access this data yourself. The relevant directories and their content are presented here.

Root directory

In the root directory there are three entries which are of relevance to the PSP. The first is the file memstick.ind which just seems to be a indication that the stick is formatted (it is not specific to the PSP). The second is the directory psp which contains subdirectories for the different types of data used by the PSP. These are game, music, photo, and savedata. Not all subdirectories may exist if no data of the corresponding type is stored. The contents of the subdirectories are detailed in the following sections. In addition, there may be a mp_root directory in the root. This directory is for storing video, and should contain only a subdirectory called 100mnv01. See the final section on this page for more information.

game

The game directory is for PSP software to be run directly from the memory stick. File formats for the binaries etc are still to be determined.

music

The music directory contains audio tracks for the music player. MPEG layer 3 files can be used as long as their filenames end with ".mp3". ID3 tags are supported and will be displayed by the player. It is possible to create subdirectories to put the tracks in, but only one level of subdirectories is supported.

photo

This directory contains picture files that can be viewed in the photo viewer. The files should be in JPEG format, and the filenames should end with ".jpg". Like with the music directory, one level of subdirectories is possible.

savedata

This is where the data saved by games goes. Each game creates a subdirectory with the product code of the game (e.g. ILJS00002) to get a private namespace, and then adds the following files to it:

icon0.png
A still picture icon in PNG format (24 bits per pixel, 14480 pixels)
icon1.pmf
An animated version of the same icon, file format currently unknown. (Optional.)
pic1.png
A full-screen background picture for the file manager in PNG format (24 bits per pixel, 480272 pixels) (Optional.)
snd0.at3
Background music to play in the file manager, ATRAC3plus encoded in a WAV file. (Optional.)
param.sfo
Metadata about the game, such as parental rating information. This is a PSF file with a category of MS.

In addition to this, the game will of course have its actual save data, typically in a file called data.bin although any name could be used as well as multiple files.

mp_root/100mnv01

Here video clips can be stored for viewing in the video player. According to the manual, the clip should be encoded using MPEG-4 (H.264/AVC MP Level3), but I have not yet found one that works... The maximum allowed bitrate is specified as 768kbps. Filenames must be on the format m4vnnnnn.mp4, where nnnnn is a 5 digit number. Remember that the mp_root directory should be in the root directory and not in the psp subdirectory.