PSn00bSDK

PSn00bSDK is a 100% free and open source SDK project for the original Sony PlayStation for developing homebrew applications and games for the console 100% freely. This SDK can be used for freeware, commercial, and open source homebrew projects.

The SDK is composed mainly of libraries (libpsn00b) and some utilities that provide a basic framework for developing software for the PlayStation hardware, the compiler is separate (GCC) and should be acquired from GNU. The library API is intentionally written to resemble the library API of the official libraries as closely as possible. This design decision is not only for familiarity reasons and so that existing sample code and tutorials would still apply, but to also make porting existing homebrew originally made with official SDKs to PSn00bSDK easier with few modifications.

PSn00bSDK is currently a work in progress and cannot really be considered production ready, but what is currently implemented should be enough to produce some interesting homebrew with the SDK, especially with extensive support for the GPU and GTE hardware. There's no reason not to fully support the hardware features of the target platform when they have been fully documented for years (nocash's PSX specs document in this case).

Most of libpsn00b is written mostly in MIPS assembly, more so functions that interface with hardware. Many of the standard C functions are implemented in custom MIPS assembly instead of equivalents found in the BIOS ROM for performance reasons.

Notable features

As of LibPSn00b run-time library v0.15b

• Extensive GPU support with polygon primitives, high-speed DMA VRAM transfers and DMA ordering table processing. All video modes for both NTSC and PAL standards also supported with fully adjustable display area and automatic video standard detection based on last GPU mode. No BIOS ROM string checks used.

• Extensive GTE support with rotate, translate, perspective correction and lighting through assembly macros (for both C and ASM) and high performance matrix and vector functions. All calculations performed in fixed point integer math.

• Stable interrupt service routine with easy to use callback system for simplified handling and hooking of hardware and DMA interrupts, no crude event handler hooks or kernel hacks used and should be compatible with HLE BIOS implementations. Should also play well with writing loader programs.

• Complete Serial I/O support with SIOCONS driver for tty console access through serial interface.

• BIOS controller functions for polling controller input work as intended thanks to proper interrupt handling. No crude manual polling of controllers in your main loop.

• Full CD-ROM support with data reading, CD audio and XA audio playback. Features built-in ISO9660 file system parser for locating files and supports directories containing more than 30 files (classic ISO9660 only, no Rock Ridge or Joliet extensions support). Data streaming should also be possible.

• Uses Sony SDK library syntax for familiarity to experienced programmers and to make porting existing homebrew projects to PSn00bSDK easier.

• Works on real hardware and most popular emulators.

Obtaining PSn00bSDK

Because PSn00bSDK is updated semi-regularly due to this project being in a work-in-progress state, it is better to obtain this SDK from source and building it yourself in the long run. Prepared packages containing precompiled libpsn00b libraries, the toolchain and additional utilities not included in this repository for Windows users are planned, though some arrangements would need to be made first. Perhaps once PSn00bSDK is considered halfway production ready.

A precompiled copy of the GCC 7.4.0 toolchain for Windows is available in the PSn00bSDK page of Lameguy64's website ( http://lameguy64.net/?page=psn00bsdk ). This should make building PSn00bSDK under Windows a bit easier as building the toolchain is the hardest part of building PSn00bSDK, as its more difficult to get it to compile correctly under Windows than on Linux and BSDs.

Building the SDK

Windows:

1. Download the following:

• MSys2 (32-bit or 64-bit version whichever you prefer)
• GCC 7.4.0 for mipsel-unknown-elf (download from Lameguy64's website at http://lameguy64.net?page=psn00bsdk )

2. Install MSys2, update packages (with pacman -Syu) then install the following packages:

• git
• make
• mingw-w64-i686-gcc (32-bit) or mingw-w64-x86_64-gcc (64-bit) You will need to close and reopen MSys2 for the PATH environment to update for MinGW.
• mingw-w64-i686-tinyxml2 (32-bit) or mingw-w64-x86_64-tinyxml2 (64-bit)

3. Extract GCC 7.4.0 for mipsel-unknown-elf to the root of your C drive.
4. Edit mipsel-unknown-elf/mipsel-unknown-elf/lib/ldscripts/elf32elmip.x and update the .text definitions as explained in toolchain.txt.
5. Add export PATH=$PATH:/c/mipsel-unknown-elf/bin to your .bash_profile file in MSys2. Test if mipsel-unknown-elf-gcc can be called from any directory in the terminal.
6. Clone from PSn00bSDK source with git clone https://github.com/lameguy64/psn00bsdk Clone it in the root of your C drive or in any location you choose.
7. Enter tools directory in PSn00bSDK and run make to build all tools. Then, run make install to consolidate all tools to a single bin directory. Add this directory to your PATH variable (with export=$PATH:/tools/bin) and make sure elf2x can be called from any directory.
8. Enter libpsn00b directory and run make to build all libpsn00b libraries.
9. Enter examples directory and run make, this also verifies if the SDK has been set up correctly. Update directory paths in sdk-common.mk when necessary.

If you prefer to do things in the Command Prompt, you can add the paths c:\msys64\usr\bin, c:\msys64\mingw64\bin (mingw32 for 32-bit), c:\mipsel-unknown-elf\bin and c:\psn00bsdk\tools\bin (paths may vary depending on where you've installed/extracted them) to your system's PATH environment variable. This way, you can invoke make and compile programs with PSn00bSDK within the Command Prompt.

Linux and Unix-likes:

1. Install gcc, make, texinfo, git and development packages of mpfr, mpc, gmp, isl and tinyxml2 libraries.
2. Build and install the GNU GCC toolchain targeting mipsel-unknown-elf (see toolchain.txt for details). Update your PATH environment variable to include the bin directory of the toolchain and make sure they can be accessed from any directory.
3. Clone from PSn00bSDK source with git clone https://github.com/lameguy64/psn00bsdk
4. Enter tools directory and run make, then make install to consolidate the tools to a bin directory. Add this directory to your PATH variable and make sure elf2x is accessible from any directory.
5. Enter the libpsn00b directory and run make. You may need to edit the common.mk file to correspond with the GCC version you're using.
6. Compile the example programs to test if the SDK is set up correctly. Update directory paths in sdk-common.mk when necessary.

Examples

There are a few examples and complete source code of n00bdemo included in the examples directory. More example programs may be added in the future and contributed example programs are welcome.

To-do List

• psxgpu: VRAM move function, few more primitives and macros yet to be implemented.

• psxgte: Higher level GTE rotate translate and perspective functions, and many matrix transformation functions yet to be implemented.

• psxspu: Plenty of work to be done. Hardware timer driven sound/music system may need to be implemented (an equivalent to the Ss* series of functions in libspu basically).

• Support for MDEC.

Usage terms

PSn00bSDK falls under the terms and conditions of the Mozilla Public License. A quick summary of this license is that PSn00bSDK can be used freely in both free and open source projects and commercial closed source projects as projects using PSn00bSDK does not necessarily have to follow the MPL as well.

If modifications to the SDK were made as part of the development of such projects that enhance its functionality, such changes must be contributed back in return.

Credits

Main developer:

• Lameguy64

Honorable mentions:

• ijacquez (for the helpful suggestions on getting C++ working)

Helpful contributors can be found in the changelog.

References used:

• nocash's PlayStation specs document (http://problemkaputt.de/psx-spx.htm)
• Tails92's PSXSDK project.