Super DISC © 1992 Sony Corp.
The Super Disc System Cartridge (often simply referred to as the Super DISC) is a rare prototype development tool associated with the ill-fated "Nintendo PlayStation" (the SNES-CD project). Developed by Sony in 1992, this cartridge was designed to interface with the prototype CD-ROM hardware. It contains the boot ROM, BIOS functions, and system diagnostic routines required to initialize the Sony CD-ROM drive and communicate with the Super Famicom console.
Functionality: The cartridge contains 256KB of WRAM and 8KB of battery-backed SRAM. It includes a hidden monitor debug menu (accessible via button combinations) which developers would have used to test hardware communication between the CD drive, the Super Famicom CPU, and the custom Sony sound chip.
The 'Super Disc' Format: The term 'Super Disc' refers to the proprietary CD-ROM format Sony intended to use for its collaboration with Nintendo. This project was planned as an add-on for the Super Famicom and a standalone hybrid console (the original 'Play Station').
Historical Context: This software represents the final stages of the Sony-Nintendo partnership before relations collapsed in 1992. It is essentially the "operating system" of a console that never saw a retail launch, making it a critical artifact for understanding the transition from the 16-bit cartridge era to the 32-bit CD-ROM generation.