The Sony PlayStation Portable is a very customizable device, but when custom firmware is installed, it becomes even more so. Firmware is what runs the PSP, and custom firmware is created by everyday users. Custom firmware will actually allow you to change what the PSP's buttons do. You will need to be running custom firmware to accomplish this, which does void your warranty. However, custom firmware is not illegal.
- Sony PSP running custom firmware
Turn on your PSP and wait for it to fully boot. Turn off the PSP by holding the "Power" button up again, continuing to hold until the PSP turns off. This completely shuts off the PSP instead of putting it into sleep mode.
Hold the right trigger of the PSP and turn it back on, continuing to hold the right trigger until the PSP reboots into the recovery menu. The recovery menu will either be in green, red or blue text.
Press down on the PSP directional pad until "Registry Hacks" is highlighted. Select it and you will see a couple of different options you can change.
Select "Button Assign" to change the "Enter" button, which is defaulted to the "X" button, to the "O" button of the PSP. Press the "O" button to exit, and select "Exit" from the main recovery menu. Your PSP will reboot and you will now be able to use the "O" button as your "Enter" button.