Preparing the PSP

You do this once. After that, the board keeps the PSP's side of PSPExp up to date over the USB cable.

What you need

• A PSP-1000 (the model PSPExp is tested on). Other models may work but have not been tried.
• Custom firmware running. PSPExp loads a small driver of its own for the USB link, which the official firmware does not allow. Any custom firmware that runs homebrew with kernel access will do; if the PSP runs other homebrew, it is ready.
• A mini-USB data cable: the kind that carries data, not one made only for charging.
• A memory stick with a few megabytes free.

Installing PSPExp on the PSP

1. On the PSP: Settings > USB Connection, and connect the PSP to a computer. Its memory stick appears as a drive.
2. Copy the PSPExp folder into PSP/GAME/ on the stick, so it ends up as PSP/GAME/PSPExp/EBOOT.PBP (and the files beside it).
   • The download: PSPExp-psp-<version>.zip on PSPExp's Releases page: unzip it at the stick's root (it holds PSP/GAME/PSPExp).
   • From this repository: scripts/build.sh, then scripts/packages/runtime-slot --install /Volumes/<stick>/PSP/GAME/PSPExp (macOS; on Linux, wherever the stick is mounted).
3. Leave USB mode. PSPExp is now under Game > Memory Stick.

Starting it

Start PSPExp from the Game menu. It shows a status page (its first line: PSPExp's version on the PSP, and its slot) while it waits for a board; plug the USB cable into the board (the board must be set up first, see its guide) and the launcher appears within a few seconds.

You can start PSPExp before or after plugging the cable in, and unplug and plug it again at any time: the launcher comes back by itself.

To leave PSPExp, press HOME and quit as from any game, or hold HOME for 2 seconds.

Things the PSP does by itself

• Updates. When the board has a newer PSPExp for the PSP, the launcher's System page shows Update the PSP. It installs the new version beside the old one and restarts into it; if the new one ever fails to start, the PSP goes back to the previous one by itself.
• Battery. The launcher's top bar shows the PSP's battery (and when it charges) next to the board's own indicators.
• Saving power. While nothing happens on screen the PSP turns its backlight off; any button turns it back on.
• The clock. Settings > Clock > PSP clock lets the board set the PSP's clock, handy when its clock battery has run flat.
• Volume. The PSP's volume buttons work as always; with Bluetooth headphones on the board, they set the headphones' volume instead, and a bar on screen shows it.

The memory stick from the board

While PSPExp runs, the board can reach the PSP's memory stick: the file manager lists it as a drive (PSP), so you can copy saves, music or pictures in either direction without USB mode. See Using PSPExp.