PSY-Q

Official SDK provided by Sony Computer Entertainment to develop software for the PlayStation 1.

MS-DOS based versions

• PSY-Q 2.0 (Programmer Tool Runtime Library Version 2.0, DTL-S2160)
• PSY-Q 2.6 (Programmer Tool Runtime Library Version 2.0, DTL-S2170)
• PSY-Q 3.0 (Programmer Tool Runtime Library Version 2.0, DTL-S2180)
• PSY-Q 3.3 (Programmer Tool Runtime Library Version 2.0, DTL-S2190)
• PSY-Q 3.5 (Programmer Tool Runtime Library Version 2.0, DTL-S3000)
• PSY-Q 3.6 (Programmer Tool Runtime Library Version 2.0, DTL-S3040)

Win32 based versions

• PSY-Q 4.0
• PSY-Q 4.3
• PSY-Q 4.4
• PSY-Q 4.5
• PSY-Q 4.6

C Compilers

Prior to PSY-Q 3.6, the compiler was shipped separately in a floppy disk called "GNU C Compiler Version 2.60 (World)", which closely resembles a late build from GCC 2.6.3 with some patches from the 2.7.0 branch (this is a speculation).

• GCC 2.6.0 [AL 1.1, MM40]: found in GNU C Compiler Version 2.60 (World)
• GCC 2.7.2 [AL 1.1, MM40]: found starting from PSY-Q 3.6 and in the Yaroze SDK
• GCC 2.7.2.SN32.3.7 Build 0001: found starting from PSY-Q 4.0
• GCC 2.8.1 SN32 BUILD 4.0.0010: found in PSY-Q 4.3, includes the source code
• TODO GCC 2.91.66: PSY-Q 4.5?
• 2.95.2 19991024 BUILD 4.0.0030: found starting from PSY-Q 4.6

PSY-Q 3.6 uses a much later build from GCC 2.6.3 and it seems to be the very last compiler that is MS-DOS compatible.

Starting from PSY-Q 4.0 there is a fully fledged 32-bit compiler from the GCC 2.7.2 branch and onwards.

Assemblers

The PSX SDK widely uses a custom assembler called ASPSX.

• ASPSX 1.07: found starting from PSY-Q 2.6 (DTL-S2170)
• ASPSX 2.21: found starting from PSY-Q 3.3 (DTL-S2190)
• ASPSX 2.34: found starting from PSY-Q 3.5 (DTL-S3000)
• ASPSX 2.56: found starting from PSY-Q 4.0
• ASPSX 2.79: found starting from PSY-Q 4.3
• ASPSX 2.86: found starting from PSY-Q 4.6

The only known GNU AS assembler is found in DTL-S3040 and in the Yaroze SDK, built for MS-DOS. It is compiled from binutils 2.6 (using BFD 2.6) and it internally targets mips-sony-psx.

Binary sections

• .text
• .data
• .bss
• .sdata
• .sbss
• .rdata
• .rodata
• .init
• .fini

TODO: what's the default sections order for EXEs? TODO: what's the section order for overlays from the SDK samples?

PSY-Q version detection

The signatures of the PSY-Q libraries can be found on GitHub. Be aware that certain games might use a mix of libraries across different PSY-Q versions. The compiler and assembler are also not necessarily bound to a specific set of PSY-Q libraries.