Let's take a look at the components inside a PlayStation, and what their capabilities are. [Be sure to check out How Video Game Consoles Work first for a general introduction to game consoles.]
Processor: 32-bit R3000A
- Processor clock speed: 33.8688 MHz
- MIPS (Million Instructions Per Second): 30
- Bus speed: 132 MB per second
- Cache: Data: 4 KB; Instruction cache: 1 KB
- Resolution: 640x480 maximum (five interlaced and four non-interlaced modes supported)
- Colors: 24-bit (16,777,216) maximum; other modes supported are 4-bit (16), 8-bit (256) and 15-bit (32,768)
- Maximum sprite size: 256 pixels high x 256 pixels wide
- Polygon rendering: 360,000 polygons per second
- Geometry engine: Provides additional hardware rendering of polygons to include Gouraud shading, texture-mapping and lighting effects
- Memory: 1 MB RAM
- MPEG decoder
- Channels: 24
- Sample rate: 44.1 KHz
- Memory: 512K RAM
- Digital effects (envelope, looping, reverb)
- MIDI support
Memory: 2 MB RAM
Operating system: Proprietary 512K ROM
Game medium: CD-ROM
- Transfer speed: 150 KB per second normal, 300 KB per second double speed
- Audio CD support
- Memory buffer: 32K
The CPU in the PSX is a RISC processor. RISC stands for reduced instruction set computer, and means that the instructions and computations performed by the processor are simpler and fewer. Also, RISC chips are superscalar -- they can perform multiple instructions at the same time. This combination of capabilities, performing multiple instructions simultaneously and completing each instruction faster because it is simpler, allows the CPU to perform better than many chips with a much faster clock speed.
To lower production costs, the CPU, graphics and audio processors are combined into a single application specific integrated circuit, or ASIC. Simply put, the ASIC is a customized chip created to manage all of the components that would otherwise be handled by three separate chips.
The games come on proprietary CD-ROM/XA discs that are read by laser, just like regular CDs. When a game is put in the console, the following happens:
- You turn the power on.
- The disc spins up to speed.
- While the disc is spinning up, the console loads portions of the operating system from ROM into RAM.
- The game initialization sequence is loaded into RAM.
- You interact with the game via the controller.
- As each specific part of the game is requested, the application code and hardware-render geometry are loaded into RAM, while the video and audio portions are usually streamed directly from the CD.
- The CPU coordinates everything. It receives the input from the controller, pulls the data from RAM and directs the graphics and audio processing.
- You are finally beaten by the game and turn it off.
Since all information is flushed from RAM when the power is turned off, you will lose any personal game data. But you can save it by using one of the special Flash memory cards. The card is inserted into one of the two slots on the front of the PSX, above the port for the controller.