# PlayStation technical specifications

The PlayStation technical specifications describe the various components of the original PlayStation video game console.

## Central processing unit (CPU)

LSI CoreWare CW33300-based core
* MIPS R3000A-compatible 32-bit RISC CPU MIPS R3051 with 5 KB L1 cache, running at 33.8688 MHz.
* The microprocessor was manufactured by LSI Logic Corp. with technology licensed from SGI.
* Features:
** Initial feature size (process node) was 0.5 micron (500 nm).
** 850k – 1M transistors
** Operating performance: 30 MIPS
** Bus bandwidth 132 MB/s
** One arithmetic/logic unit (ALU)
** One shifter
* CPU cache RAM:
** 4 KB instruction cache
** 1 KB data cache configured as a scratchpad
Geometry Transformation Engine (GTE)
* Coprocessor that resides inside the main CPU processor, giving it additional vector math instructions used for 3D graphics, lighting, geometry, polygon and coordinate transformations – GTE performs high-speed matrix multiplications.
* Operating performance: 66 MIPS
* Uses fixed point arithmetic, different operations used different representations
* Polygons per second (rendered in hardware):
** 90,000 with texture mapping, lighting and Gouraud shading
** 180,000 with texture mapping
** 360,000 with flat shading
Motion Decoder (MDEC)
* Also residing within the main CPU, enables full screen, high quality FMV playback and is responsible for decompressing images and video into VRAM.
* Operating performance: 80 MIPS
* Documented device mode is to read three RLE-encoded 16×16 macroblocks, run IDCT and assemble a single 16×16 RGB macroblock.
* Output data may be transferred directly to GPU via DMA.
* It is possible to overwrite IDCT matrix and some additional parameters, however MDEC internal instruction set was never documented.
* It is directly connected to a CPU bus.
System Control Coprocessor (Cop0)
* This unit is part of the CPU. Has 16 32-bit control registers.
* Modified from the original R3000A cop0 architecture, with the addition of a few registers and functions.
* Controls memory management through virtual memory technique, system interrupts, exception handling, and breakpoints.

## Memory

* 2 MiB main EDO DRAM
* Additional RAM is integrated with the GPU (including a 1 MB framebuffer) and SPU (512 KB), see below for details.
* Cache RAM for CPU core and CD-ROM. See the relevant sections for details.
* Flash RAM support through the use of memory cards, see below.
* BIOS stored on 512 KB ROM

## Graphics processing unit (GPU)

32-bit Sony GPU (designed by Toshiba)
* Handles display of graphics, control of framebuffer, and drawing of polygons and textures
* Handles 2D graphics processing, in a similar manner to the 3D engine
* RAM:
** 1 MB VRAM (later models contained SGRAM) for framebuffer
** 2 KB texture cache (132 MB/s memory bus bandwidth, 32-bit wide)
** 64 bytes FIFO buffer
* Features:
** Adjustable framebuffer (1024×512)
** Emulation of simultaneous backgrounds (to simulate parallax scrolling)
** Mask bit
** Texture window
** Dithering
** Clipping
** Alpha blending (4 per-texel alpha blending modes)
** Fog
** Framebuffer effects
** Transparency effects
** Render to texture
** Offscreen rendering
** Multipass rendering
** Flat or Gouraud shading and texture mapping
** No line restriction
** Colored light sourcing
* Resolutions:
** Progressive: 256×224 to 640×240 pixels
** Interlaced: 256×448 to 640×480 pixels
* Colors:
** Maximum color depth of 16,777,216 colors (24-bit true color)
** 57,344 (256×224) to 153,600 (640×240) colors on screen
** Unlimited color lookup tables (CLUTs)
** 32 levels of transparency
** All calculations are performed to 24 bit accuracy
* Texture mapping color mode:
** Mode 4: 4-bit CLUT (16 colors)
** Mode 8: 8-bit CLUT (256 colors)
** Mode 15: 15-bit direct (32,768 colors)
** Mode 24: 24-bit (16,777,216 colors)
* Sprite engine
** 1024×512 framebuffer, 8×8 and 16×16 sprite sizes, bitmap objects
** Up to 4,000 sprites on screen (at 8×8 sprite size), scaling and rotation
** 256×256 maximum sprite size
* Special sprite effects:
** Rotation
** Scaling up/down
** Warping
** Transparency
** Fading
** Priority
** Vertical and horizontal line scroll
* Pixel fillrate (theoretical maximum):
** 66 MPixel/s flat shaded polygons
** 33 MPixel/s Gouraud shaded polygons
** 33 MPixel/s for textured polygons with optional Gourard shading
** Actual fill rate is lower due to polygon overhead or texture cache misses

## Sound processing unit (SPU)

16-bit Sony SPU
* Supports ADPCM sources with up to 24 channels
* Sampling rate of up to 44.1 kHz
* 512 KB RAM
* PCM audio source
* Supports MIDI sequencing
* Digital effects include:
** Pitch modulation
** Envelope
** Looping
** Digital reverb

## I/O system and connectivity

CD-ROM drive
* 660 MB maximum storage capacity, double speed (CLV) CD-ROM drive
* 2×, with a maximum data throughput of 300 KB/s (double speed), 150 KB/s (normal)
* 32 KB data buffer
* XA Mode 2 compliant
* Audio CD play
* CD-DA (CD-Digital Audio)
* Rated for 70,000 seek operations
Two control pads via connectors
* Expandable with multitap connector
Backup flash RAM support
* Two removable cards
* Each card has 128 KB flash memory
* OS support for File Save, Retrieve and Remove
* Some games (like "Music 2000") can use Memory Cards as main RAM, to store data for real time processing, bypassing the 2MB RAM limit.
Video and audio connectivity
* AV Multi Out (Composite video, S-Video, RGBS)
* RCA Composite video and Stereo out (SCPH-100x to 5000 only)
* RFU (SCPH-112X) DC out (SCPH-100x to 5000 only)
* S-Video out (SCPH-1000 only)
Serial and parallel ports
* Serial I/O (used for PlayStation Link Cable SCPH-100x to 900x only)
* Parallel I/O (N/A) SCPH-100x to 750x only)
Power input
* 100 V AC (NTSC-J); 120 V AC (NTSC-U/C); or 220–240 V AC (PAL)
* 7.5 V DC 2 A (PSone only)