SMS Plus PSP is a port of the SMS Plus emulator to the Sony PlayStation Portable platform. It’s written in C and uses GU (Graphical Utility toolkit) for rendering.

New Features
Version 1.2.55 (January 14 2009)

* Time Rewind feature by DaveX – “rewind� recent gameplay (approximately 20 seconds). Map ‘Special: Rewind’ to any PSP button to enable this feature

Installation

Unzip smsppsp.zip into /PSP/GAME/ folder on the memory stick.

Game ROM’s may reside anywhere (the ROMS subdirectory is recommended, but not necessary). SMS+ PSP can load ROM’s from ZIP files.
Time Rewinding

Starting with version 1.2.55, SMS Plus PSP includes a “time rewind� feature, which allows you to rewind recent gameplay (approximately 20 seconds). Map ‘Special: Rewind’ to any PSP button to enable this feature.
Controls

The emulator currently comes with the following default key mappings:

During emulation:
Analog stick Directional pad up/down/left/right
Directional pad Directional pad up/down/left/right
[ ] (square) Button 2
X (cross) Button 1
O (circle) Spacebar
[L] + [R] Return to the emulator menu
START Pause/Start

By default, button configuration changes are not retained after button mapping is modified. To save changes, press X (cross) after desired mapping is configured. To load the default mapping press ^ (triangle).
Compiling

Emulator’s source code is only available via a Subversion (SVN) repository. To check out a particular version, run

svn co http://svn.akop.org/psp/tags/smsplus/version

where version is the release version (for example, 1.2.1). Note that for this to work, you need to have Subversion installed.

To compile the emulator, you will need zlib (svn://) and libpng (svn://).