PSn00bSDK

PSn00bSDK is an open source homebrew software development kit for the original Sony PlayStation, consisting of a C/C++ compiler toolchain and a set of libraries that provide a layer of abstraction over the raw hardware in order to make game and app development easier. A CMake-based build system, CD-ROM image packing tool (mkpsxiso) and asset conversion utilities are also provided.

At the heart of PSn00bSDK is libpsn00b, a set of libraries that implements most of the core functionality of the official Sony SDK (excluding higher-level libraries) plus several new extensions to it. Most of the basic APIs commonly used by homebrew apps and games built with the official SDK are available, making PSn00bSDK a good starting point for those who have an existing codebase but want to move away from Sony tools.

Currently supported features include:

• Full support for the GPU's functionality including all primitive types (lines, polygons, sprites) as well DMA transfers managed through a software-driven command queue that can optionally be extended with custom commands. Both NTSC and PAL video modes are fully supported.

• Extensive GTE support with rotate, translate, perspective correction and lighting calculation fully supported through C and/or assembly GTE macros paired with high speed matrix and vector helper functions. All calculations performed in fixed point integer math, not a single float used.

• BIOS-based interrupt dispatch system providing the ability to register custom callbacks for all IRQs and DMA channels while preserving compatibility with all functions provided by the BIOS.

• Basic support for controller input through the BIOS, with optional limited support for manual polling.

• Complete Serial I/O support with buffering and console driver to redirect BIOS standard input and output to the serial port. Hardware flow control supported.

• CD-ROM support featuring asynchronous reading, CD-DA and XA-ADPCM audio playback and a built-in ISO9660 file system parser with no file count limit. Additional support for multi-session discs and bypassing region checks on supported console models.

• Full MDEC support for hardware accelerated lossy image decompression and video playback.

• Preliminary limited support for Konami System 573 arcade hardware.

• Experimental support for dynamic linking at runtime, including function and variable introspection by loading a map file generated at build time.

Note that, while PSn00bSDK's API is to some extent compatible with the official SDK's, the project is not meant to be a drop-in replacement for it, both since reimplementing the entire SDK would be a major undertaking and because many parts of it are inefficient, clunky and/or provide relatively little value.

Obtaining PSn00bSDK

Prebuilt PSn00bSDK packages for Windows and Linux are available on the releases page and include the libraries, a copy of the GCC MIPS toolchain, command-line tools, examples and documentation. CMake is not included and must be installed separately, either from its website or via MSys2 or your distro's package manager.

The releases can be installed by simply extracting the archives into any directory and adding the bin subfolder to the PATH environment variable. share/psn00bsdk/template contains a barebones example project that can be used as a starting point.

For more information on how to get started, or if you wish to build the SDK yourself from source instead, refer to installation.md.

Tutorials and examples

The examples directory contains several example programs showcasing different parts of the SDK (mostly graphics); the source code of n00bdemo can also be found in the same directory. More example programs may be added in the future and contributed example programs are welcome.

Lameguy's PlayStation Programming Tutorial Series was written with older versions of PSn00bSDK in mind and is outdated at this point, but may still be useful as an introduction to the console's hardware and the basics of the graphics and controller APIs.

To-do List

• libpsxgte: Rewrite all assembly functions from scratch as parts of them have been lifted as-is from Sony libraries. PSn00bSDK is currently (and will probably always be) in a legal gray area due to this.

• libpsxspu: Plenty of work to be done. Some kind of MIDI sequencer (similar to the one present in the official SDK) should be added at some point, along with a proper API for audio streaming.

• libpsxcd: Implement a command queue mechanism for the CD-ROM.

• libpsxpress: Add an API for SPU-ADPCM audio encoding at runtime.

• libc: Improve the memory allocation framework with multiple allocators, replace the string functions with optimized implementations and maybe add helpers to manage swapping between main RAM and VRAM/SPU RAM.

• Add a full controller and memory card API that does not depend on the BIOS controller driver, and possibly a library for interfacing to IDE/ATAPI drives to make development for arcade systems easier.

Credits

Main developers/authors:

• Lameguy64 (John "Lameguy" Wilbert Villamor)
• spicyjpeg

Contributors:

• Silent, G4Vi, Chromaryu: mkpsxiso and dumpsxiso (maintained as a separate repo).

Honorable mentions:

• Soapy: wrote the original version of the inline_c.h header containing GTE macros.
• ijacquez: helpful suggestions for getting C++ working.
• Nicolas Noble: author of the pcsx-redux emulator, OpenBIOS and other projects which proved invaluable during development.

Helpful contributors can be found in the changelog.

References used:

• Martin Korth's psx-spx document and the community-maintained version.
• MIPS and System V ABI specs (for the dynamic linker).
• Tails92's PSXSDK project (during PSn00bSDK's infancy).

Additional references can be found in individual source files.